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1.
J Biol Chem ; 295(20): 7003-7017, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32273342

RESUMO

Cholelithiasis is one of the most prevalent gastroenterological diseases and is characterized by the formation of gallstones in the gallbladder. Both clinical and preclinical data indicate that obesity, along with comorbidity insulin resistance, is a predisposing factor for cholelithiasis. Forkhead box O1 (FoxO1) is a key transcription factor that integrates insulin signaling with hepatic metabolism and becomes deregulated in the insulin-resistant liver, contributing to dyslipidemia in obesity. To gain mechanistic insights into how insulin resistance is linked to cholelithiasis, here we determined FoxO1's role in bile acid homeostasis and its contribution to cholelithiasis. We hypothesized that hepatic FoxO1 deregulation links insulin resistance to impaired bile acid metabolism and cholelithiasis. To address this hypothesis, we used the FoxO1LoxP/LoxP-Albumin-Cre system to generate liver-specific FoxO1-knockout mice. FoxO1-knockout mice and age- and sex-matched WT littermates were fed a lithogenic diet, and bile acid metabolism and gallstone formation were assessed in these animals. We showed that FoxO1 affected bile acid homeostasis by regulating hepatic expression of key enzymes in bile acid synthesis and in biliary cholesterol and phospholipid secretion. Furthermore, FoxO1 inhibited hepatic expression of the bile acid receptor farnesoid X receptor and thereby counteracted hepatic farnesoid X receptor signaling. Nonetheless, hepatic FoxO1 depletion neither affected the onset of gallstone disease nor impacted the disease progression, as FoxO1-knockout and control mice of both sexes had similar gallstone weights and incidence rates. These results argue against the notion that FoxO1 is a link between insulin resistance and cholelithiasis.


Assuntos
Ácidos e Sais Biliares/metabolismo , Proteína Forkhead Box O1/metabolismo , Cálculos Biliares/metabolismo , Resistência à Insulina , Transdução de Sinais , Animais , Ácidos e Sais Biliares/genética , Colesterol/genética , Colesterol/metabolismo , Feminino , Proteína Forkhead Box O1/genética , Cálculos Biliares/genética , Deleção de Genes , Regulação da Expressão Gênica , Fígado , Masculino , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Fosfolipídeos/genética , Fosfolipídeos/metabolismo , Receptores Citoplasmáticos e Nucleares/biossíntese , Receptores Citoplasmáticos e Nucleares/genética
2.
J Insect Sci ; 20(4)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32809023

RESUMO

The male accessory glands (MAGs) in insects are pair(s) of internal reproductive organs that produce and secrete the plasma component of seminal fluid. In various insects, MAG size is important for male reproductive success because the fluid provides physiologically active substances and/or nutrients to females to control sperm as well as female reproductive behaviors. Although the MAG epithelial cells in most insect species are standard mononucleate cells, those in some insect taxa are binucleate due to incomplete cytokinesis (e.g., Drosophila [Fallén] [Diptera: Drosophilidae]) or cell fusion (e.g., Cimex [Linnaeus] [Hemiptera: Cimicidae]). In the case of Drosophila, the apicobasal position of the two nuclei relative to the epithelial plane changes from vertical to horizontal after nutrient intake, which allows the volume of the MAG cavity to expand effectively. On the other hand, in the case of Cimex, the positions of the two nuclei do not change apicobasally in response to feeding, but their position relative to the proximodistal axis varies depending on the tubular/spherical organ morphology. Here, we report that the MAG of the benthic water bug Aphelocheirus vittatus (Matsumura) (Hemiptera: Aphelochiridae) shows binucleation in all epithelial cells. Despite the phylogenetically close relationship between Aphelocheirus and Cimex, the MAG cells in Aphelocheirus showed a Drosophila-like apicobasal change in the position of the two nuclei in response to feeding. Furthermore, the cytological processes during binucleation are more similar to those in Drosophila (incomplete cytokinesis) than to those in Cimex (cell fusion). These results indicate that the physiological role and mechanism of binucleation in MAG cells changed during the evolution of Hemiptera.


Assuntos
Hemípteros/anatomia & histologia , Hemípteros/crescimento & desenvolvimento , Animais , Genitália/anatomia & histologia , Genitália/crescimento & desenvolvimento , Genitália/ultraestrutura , Hemípteros/ultraestrutura , Masculino , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Ninfa/anatomia & histologia , Ninfa/crescimento & desenvolvimento , Ninfa/ultraestrutura
3.
J Biol Chem ; 292(9): 3692-3705, 2017 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-28115523

RESUMO

Nonalcoholic fatty liver disease (NAFLD), characterized by excessive fat accumulation in liver, is prevalent in obesity. Genetic factors that link obesity to NAFLD remain obscure. Apolipoprotein C3 (APOC3) is a lipid-binding protein with a pivotal role in triglyceride metabolism. Humans with APOC3 gain-of-function mutations and mice with APOC3 overproduction are associated with hypertriglyceridemia. Nonetheless, it remains controversial whether APOC3 is culpable for diet-induced NAFLD. To address this fundamental issue, we fed APOC3-transgenic and wild-type littermates a high fructose diet or high fat diet, followed by determination of the effect of APOC3 on hepatic lipid metabolism and inflammation and the progression of NAFLD. To gain mechanistic insight into NAFLD, we determined the impact of APOC3 on hepatic triglyceride synthesis and secretion versus fatty acid oxidation. APOC3-transgenic mice were hypertriglyceridemic, culminating in marked elevation of triglycerides, cholesterols, and non-esterified fatty acids in plasma. Despite the prevailing hypertriglyceridemia, APOC3-transgenic mice, relative to wild-type littermates, had similar weight gain and hepatic lipid content without alterations in hepatic expression of key genes involved in triglyceride synthesis and secretion and fatty acid oxidation. APOC3-transgenic and wild-type mice had similar Kupffer cell content without alterations in hepatic expression of pro- and anti-inflammatory cytokines. APOC3 neither exacerbated diet-induced adiposity nor aggravated the degree of steatosis in high fructose or high fat-fed APOC3-transgenic mice. These effects ensued independently of weight gain even after 10-month high fat feeding. We concluded that APOC3, whose dysregulation is liable for hypertriglyceridemia, is not a predisposing factor for linking overnutrition to NAFLD in obesity.


Assuntos
Apolipoproteína C-III/genética , Apolipoproteína C-III/metabolismo , Regulação da Expressão Gênica , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Peso Corporal , Colesterol/metabolismo , Citocinas/metabolismo , Dieta Hiperlipídica , Feminino , Frutose/química , Predisposição Genética para Doença , Teste de Tolerância a Glucose , Hipertrigliceridemia/metabolismo , Inflamação , Resistência à Insulina/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/química , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Obesidade/metabolismo , Regiões Promotoras Genéticas , Transgenes , Triglicerídeos/metabolismo , Aumento de Peso
4.
Chemistry ; 24(65): 17293-17302, 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30378204

RESUMO

A unique superparamagnetic-like behavior and a large "positive magneto-LC effect" were observed in the solid phases and the hexagonal columnar (Colh ) liquid crystalline (LC) phase, respectively, of novel achiral non-π-delocalized nitroxide diradical compounds (R,S)-1, which showed polymorphism in the solid phases (solids I and II). The SQUID magnetization measurement revealed that (1) (R,S)-1 containing a small amount of racemic diastereomers (R*,R*)-1 possessed an unusual and large temperature-independent magnetic susceptibility (χTIM >0) component in the original nanocrystalline solid I that was responsible for the observed superparamagnetic-like behavior under low magnetic fields and did not arise from the contamination by extrinsic magnetic metal or metal ion impurities, besides ordinary temperature-dependent paramagnetic susceptibility (χpara >0) and temperature-independent diamagnetic susceptibility (χdia <0) components, (2) a large increase in molar magnetic susceptibility (χM ) (positive magneto-LC effect) that occurred at the solid I-to-liquid crystal transition upon heating was preserved as an additional χTIM increase in the resulting polymorphic nanocrystalline solid II by cooling, and (3) such unique magnetic phenomena were induced by thermal processing for (R,S)-1 or by adding a small amount of (R*,R*)-1 to (R,S)-1 as the impurity.

5.
J Biol Chem ; 291(28): 14695-705, 2016 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-27226540

RESUMO

Hypertriglyceridemia results from increased production and decreased clearance of triglyceride-rich very low-density lipoproteins, a pathological condition that accounts for heightened risk of ischemic vascular diseases in obesity and type 2 diabetes. Despite its intimate association with insulin resistance, whether hypertriglyceridemia constitutes an independent risk for beta cell dysfunction in diabetes is unknown. Answering this fundamental question is stymied by the fact that hypertriglyceridemia is intertwined with hyperglycemia and insulin resistance in obese and diabetic subjects. To circumvent this limitation, we took advantage of apolipoprotein C3 (ApoC3)-transgenic mice, a model with genetic predisposition to hypertriglyceridemia. We showed that ApoC3-transgenic mice, as opposed to age/sex-matched wild-type littermates, develop hypertriglyceridemia with concomitant elevations in plasma cholesterol and non-esterified fatty acid levels. Anti-insulin and anti-glucagon dual immunohistochemistry in combination with morphometric analysis revealed that ApoC3-transgenic and wild-type littermates had similar beta cell and alpha cell masses as well as islet size and architecture. These effects correlated with similar amplitudes of glucose-stimulated insulin secretion and similar degrees of postprandial glucose excursion in ApoC3-transgenic versus wild-type littermates. Oil Red O histology did not visualize lipid infiltration into islets, correlating with the lack of ectopic triglyceride and cholesterol depositions in the pancreata of ApoC3-transgenic versus wild-type littermates. ApoC3-transgenic mice, despite persistent hypertriglyceridemia, maintained euglycemia under both fed and fasting conditions without manifestation of insulin resistance and fasting hyperinsulinemia. Thus, hypertriglyceridemia per se is not an independent risk factor for beta cell dysfunction in ApoC3 transgenic mice.


Assuntos
Apolipoproteína C-III/metabolismo , Diabetes Mellitus Tipo 2/complicações , Hipertrigliceridemia/complicações , Células Secretoras de Insulina/patologia , Animais , Apolipoproteína C-III/genética , Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Glucose/metabolismo , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/metabolismo , Hipertrigliceridemia/patologia , Resistência à Insulina , Células Secretoras de Insulina/metabolismo , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Obesidade
6.
Chemistry ; 23(62): 15713-15720, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-28815766

RESUMO

With a view to developing a theranostic nanomedicine for targeted drug delivery systems visible by magnetic resonance (MR) imaging, robust metal-free magnetic nanoemulsions (mean particle size less than 20 nm) consisting of a biocompatible surfactant and hydrophobic, low molecular weight 2,2,5-trimethyl-5-(4-alkoxy)phenylpyrrolidine-N-oxyl radicals were prepared in pH 7.4 phosphate-buffered saline (PBS). The structure of the nanoemulsions was characterized by electron paramagnetic resonance spectroscopy, and dynamic light scattering and small-angle neutron-scattering measurements. The nanoemulsions showed high colloidal stability, low cytotoxicity, enough reduction resistance to excess ascorbic acid, and sufficient contrast enhancement in the proton longitudinal relaxation time (T1 ) weighted MR images in PBS in vitro (and preliminarily in vivo). Furthermore, the hydrophobic anticancer drug paclitaxel could be encapsulated inside the nanoparticles, and the resulting paclitaxel-loaded nanoemulsions were efficiently incorporated into HeLa cells to suppress cell growth.


Assuntos
Antineoplásicos Fitogênicos/química , Portadores de Fármacos/química , Nanopartículas de Magnetita/química , Óxidos de Nitrogênio/química , Paclitaxel/química , Animais , Antineoplásicos Fitogênicos/toxicidade , Ácido Ascórbico/química , Encéfalo/diagnóstico por imagem , Proliferação de Células/efeitos dos fármacos , Difusão Dinâmica da Luz , Espectroscopia de Ressonância de Spin Eletrônica , Células HeLa , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imageamento por Ressonância Magnética , Camundongos , Peso Molecular , Difração de Nêutrons , Oxirredução , Paclitaxel/toxicidade , Tamanho da Partícula , Espalhamento a Baixo Ângulo
7.
J Biol Chem ; 290(25): 15581-15594, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25944898

RESUMO

Excessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. FoxO6 is a distinct member of the FoxO subfamily. To elucidate the role of FoxO6 in hepatic gluconeogenesis and assess its contribution to the pathogenesis of fasting hyperglycemia in diabetes, we generated FoxO6 knock-out (FoxO6-KO) mice followed by determining the effect of FoxO6 loss-of-function on hepatic gluconeogenesis under physiological and pathological conditions. FoxO6 depletion attenuated hepatic gluconeogenesis and lowered fasting glycemia in FoxO6-KO mice. FoxO6-deficient primary hepatocytes were associated with reduced capacities to produce glucose in response to glucagon. When fed a high fat diet, FoxO6-KO mice exhibited significantly enhanced glucose tolerance and reduced blood glucose levels accompanied by improved insulin sensitivity. These effects correlated with attenuated hepatic gluconeogenesis in FoxO6-KO mice. In contrast, wild-type littermates developed fat-induced glucose intolerance with a concomitant induction of fasting hyperinsulinemia and hyperglycemia. Furthermore, FoxO6-KO mice displayed significantly diminished macrophage infiltration into liver and adipose tissues, correlating with the reduction of macrophage expression of C-C chemokine receptor 2 (CCR2), a factor that is critical for regulating macrophage recruitment in peripheral tissues. Our data indicate that FoxO6 depletion protected against diet-induced glucose intolerance and insulin resistance by attenuating hepatic gluconeogenesis and curbing macrophage infiltration in liver and adipose tissues in mice.


Assuntos
Gorduras na Dieta/efeitos adversos , Fatores de Transcrição Forkhead/metabolismo , Gluconeogênese/efeitos dos fármacos , Hiperglicemia/metabolismo , Hiperinsulinismo/metabolismo , Fígado/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Células Cultivadas , Gorduras na Dieta/farmacologia , Fatores de Transcrição Forkhead/genética , Gluconeogênese/genética , Hiperglicemia/induzido quimicamente , Hiperglicemia/genética , Hiperglicemia/patologia , Hiperglicemia/prevenção & controle , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/genética , Hiperinsulinismo/patologia , Hiperinsulinismo/prevenção & controle , Fígado/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Knockout , Receptores CCR2/genética , Receptores CCR2/metabolismo
8.
Soft Matter ; 11(27): 5563-70, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26073537

RESUMO

An optically active amphiphilic nitroxide radical compound [(S,S,R)-], which contains a paramagnetic (2S,5S)-2,5-dimethyl-2,5-diphenylpyrrolidine-N-oxyl radical group fixed in the inner position together with a hydrophobic long alkyl chain and a hydrophilic (R)-alanine residue in the opposite terminal positions, was found to serve as a low-molecular-weight gelator in H2O to give rise to a spin-labelled physical hydrogel. Characterization of the hydrogel was performed by microscopic (SEM, TEM and AFM) techniques, XRD and SAXS measurements, and IR, UV and CD spectroscopies. The gel-sol transition temperature was determined by EPR spectral line-width (ΔHpp) analysis. Measurement of the temperature dependence of relative paramagnetic susceptibility (χrel) for the hydrogel and sol phases was achieved by means of the double-integration of VT-EPR spectra.


Assuntos
Hidrogéis/síntese química , Óxidos de Nitrogênio/química , Espectroscopia de Ressonância de Spin Eletrônica , Interações Hidrofóbicas e Hidrofílicas , Pirrolidinas/química , Marcadores de Spin , Estereoisomerismo , Temperatura de Transição
9.
J Biol Chem ; 288(35): 25350-25361, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-23888053

RESUMO

Hypertriglyceridemia is the most common lipid disorder in obesity and type 2 diabetes. It results from increased production and/or decreased clearance of triglyceride-rich lipoproteins. To better understand the pathophysiology of hypertriglyceridemia, we studied hepatic regulation of triglyceride metabolism by the activating transcription factor 4 (ATF4), a member of the basic leucine zipper-containing protein subfamily. We determined the effect of ATF4 on hepatic lipid metabolism in Atf4(-/-) mice fed regular chow or provided with free access to fructose drinking water. ATF4 depletion preferentially attenuated hepatic lipogenesis without affecting hepatic triglyceride production and fatty acid oxidation. This effect prevented excessive fat accumulation in the liver of Atf4(-/-) mice, when compared with wild-type littermates. To gain insight into the underlying mechanism, we showed that ATF4 depletion resulted in a significant reduction in hepatic expression of peroxisome proliferator-activated receptor-γ, a nuclear receptor that acts to promote lipogenesis in the liver. This effect was accompanied by a significant reduction in hepatic expression of sterol regulatory element-binding protein 1c (SREBP-1c), acetyl-CoA carboxylase, and fatty-acid synthase, three key functions in the lipogenic pathway in Atf4(-/-) mice. Of particular significance, we found that Atf4(-/-) mice, as opposed to wild-type littermates, were protected against the development of steatosis and hypertriglyceridemia in response to high fructose feeding. These data demonstrate that ATF4 plays a critical role in regulating hepatic lipid metabolism in response to nutritional cues.


Assuntos
Fator 4 Ativador da Transcrição , Frutose/efeitos adversos , Hipertrigliceridemia , Metabolismo dos Lipídeos , Fígado/metabolismo , Edulcorantes/efeitos adversos , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Animais , Ácido Graxo Sintase Tipo I/genética , Ácido Graxo Sintase Tipo I/metabolismo , Frutose/farmacologia , Hipertrigliceridemia/induzido quimicamente , Hipertrigliceridemia/genética , Hipertrigliceridemia/metabolismo , Hipertrigliceridemia/patologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Fígado/patologia , Camundongos , Camundongos Knockout , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Edulcorantes/farmacologia
10.
J Bone Miner Metab ; 32(2): 142-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23702931

RESUMO

Menaquinone-4 (MK-4) administered at a pharmacological dosage of 45 mg/day has been used for the treatment of osteoporosis in Japan. However, it is not known whether a lower dose of MK-4 supplementation is beneficial for bone health in healthy postmenopausal women. The aim of this study was to examine the long-term effects of 1.5-mg daily supplementation of MK-4 on the various markers of bone turnover and bone mineral density (BMD). The study was performed as a randomized, double-blind, placebo-controlled trial. The participants (aged 50-65 years) were randomly assigned to one of two groups according to the MK-4 dose received: the placebo-control group (n = 24) and the 1.5-mg MK-4 group (n = 24). The baseline concentrations of undercarboxylated osteocalcin (ucOC) were high in both groups (>5.1 ng/ml). After 6 and 12 months, the serum ucOC concentrations were significantly lower in the MK-4 group than in the control group. In the control group, there was no significant change in serum pentosidine concentrations. However, in the MK-4 group, the concentration of pentosidine at 6 and 12 months was significantly lower than that at baseline. The forearm BMD was significantly lower after 12 months than at 6 months in the control group. However, there was no significant decrease in BMD in the MK-4 group during the study period. These results suggest that low-dose MK-4 supplementation for 6-12 months improved bone quality in the postmenopausal Japanese women by decreasing the serum ucOC and pentosidine concentrations, without any substantial adverse effects.


Assuntos
Suplementos Nutricionais , Osteoporose Pós-Menopausa/prevenção & controle , Pós-Menopausa , Vitamina K 2/metabolismo , Idoso , Biomarcadores/sangue , Densidade Óssea , Cromatografia Líquida de Alta Pressão , Método Duplo-Cego , Feminino , Antebraço , Humanos , Japão , Pessoa de Meia-Idade , Inquéritos e Questionários , Fatores de Tempo , Vitamina K 2/sangue , Vitamina K 2/urina
11.
Biosci Biotechnol Biochem ; 77(8): 1785-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23924720

RESUMO

The production of retinol binding protein 4 (RBP4) is higher in adipose tissue in type 2 diabetes. We have found that proteasome subunit beta type 1 (PSMB1) is a transcriptional activator of Rbp4. In the present study, the putative tyrosine phosphorylation site in PSMB1 was mutated to phenylalanine. The mutated form of PSMB1 displayed increased nuclear translocation, resulting in activation of transcription in adipocytes.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/metabolismo , Ativação Transcricional , Adipócitos/metabolismo , Diabetes Mellitus Tipo 2/genética , Humanos , Técnicas de Transferência Nuclear , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Plasmáticas de Ligação ao Retinol/genética , Transdução de Sinais
12.
Tohoku J Exp Med ; 229(2): 143-6, 2013 02.
Artigo em Inglês | MEDLINE | ID: mdl-23343691

RESUMO

Familial adenomatous polyposis is an autosomal dominant hereditary disease leading to the development of numerous colorectal polyps with malignant potential. Extra-colonic neoplasms are observed often in patients with familial adenomatous polyposis, but clinical characteristics of gastric cancer associated with familial adenomatous polyposis are not well understood. We studied the clinical characteristics of five Japanese patients who developed gastric cancer after undergoing colectomy for familial adenomatous polyposis. Gastric cancer was found on gastroduodenal endoscopy performed during postoperative follow-up in all five patients. Mean ages at the time of colectomy and at the time of diagnosis of gastric cancer were 39.2 and 58 years, respectively. Importantly, gastric fundic gland polyps were undetectable in these five patients. The mean duration between colectomy and diagnosis of gastric cancer was more than 20 years in three of five patients (mean: 19 years and 1 month). Cancers were multiple in three of five patients. Two patients developed metachronous gastric cancer in the gastric remnant. All five patients presented with well to moderately differentiated adenocarcinoma; four of the five patients were stage IA. Characteristics of the gastric cancer with familial adenomatous polyposis include a long duration between occurrence of gastric cancer and colectomy, metachronous cancers, multicentric lesions, and a high rate of well to moderately differentiated adenocarcinoma. Long-term and periodic gastroduodenal surveillance endoscopy is recommended for patients with FAP who underwent colectomy.


Assuntos
Adenocarcinoma/patologia , Polipose Adenomatosa do Colo/patologia , Segunda Neoplasia Primária , Neoplasias Gástricas/patologia , Polipose Adenomatosa do Colo/cirurgia , Adulto , Idoso , Colectomia , Endoscopia Gastrointestinal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Fatores de Tempo
13.
Nihon Shokakibyo Gakkai Zasshi ; 110(7): 1296-303, 2013 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-23831661

RESUMO

Hemorrhage through the pancreatic duct into the duodenum, the so-called "hemosuccus pancreaticus", is a rare cause of gastrointestinal bleeding. A 75-year-old man, who was treated with anticoagulation agents for an old myocardial infarction, was admitted to our hospital for sudden tarry stools and abdominal pain. His hemoglobin level slightly dropped to 12.6g/dL. His liver function tests results and the serum amylase level were elevated. A second upper gastrointestinal endoscopy revealed continuous bleeding from the ampulla of Vater. A rupture of an aneurysm of the splenic artery to the pancreatic duct was suggested by abdominal computed tomographic scan, abdominal magnetic resonance imaging, celiac arteriography, and endoscopic ultrasonography. The conservative treatment of stopping the bleeding with anticoagulation agents was successful.


Assuntos
Aneurisma Roto/complicações , Hemorragia/etiologia , Pancreatopatias/etiologia , Ductos Pancreáticos , Artéria Esplênica , Idoso , Humanos , Masculino
14.
Sci Rep ; 13(1): 20742, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007567

RESUMO

In this study, the fraction extracted from turmeric powder with 50% ethanol and fractionated with n-hexane were administered to diet-induced NASH model rats. NASH model was prepared with SD rats by feeding an originally designed choline-deficient, high-fat, high-fructose (HFF-CD) diet for 10 weeks. To the HFF-CD diet, hexane fraction and 50% ethanol fraction after hexane fractionation were added at 100 mg/kg body weight. 10 weeks later, blood samples and liver were collected for the following parameters: lipid weights, serum ALT, AST, TG, liver TG, TBARS levels, lipid metabolism-related gene expression and histopathological examination of the liver. As the results, the hexane fraction and 50% ethanol fraction showed a decrease in lipid weight, a decrease in hepatic TG, and activation of PPAR-α in the lipid metabolism-related gene test. These results suggest that the hexane fraction of turmeric has an inhibitory effect on fat accumulation in the liver by promoting lipid metabolism in NASH model rats.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Curcuma , Hexanos/metabolismo , Ratos Sprague-Dawley , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Cirrose Hepática/patologia , Lipídeos/farmacologia , Etanol/farmacologia , Metabolismo dos Lipídeos/genética
15.
Biosci Biotechnol Biochem ; 76(8): 1588-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22878203

RESUMO

Vitamin D(3) initiated rapid extracellular signal-related kinase (ERK) phosphorylation, but the contribution of vitamin D receptor (VDR) to this event is unclear. We investigated the use of RNA interference (RNAi) to knockdown VDR. RNAi downregulated VDR as well as its targeted gene expression, but vitamin D(3) dependent ERK phosphorylation remained. Thus VDR might not be involved in ERK phosphorylation by vitamin D(3).


Assuntos
Regulação da Expressão Gênica , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Receptores de Calcitriol/genética , Células CACO-2 , Colecalciferol/metabolismo , Colecalciferol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno/genética , Receptores de Calcitriol/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
16.
Sci Rep ; 12(1): 996, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046433

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of extracellular amyloid-beta peptides (Aß) resulting in senile plaques and intracellular hyperphosphorylated tau protein resulting in neurofibrillary tangles (NFTs). Mucuna beans (Mucuna pruriences (L.) DC. var. utilis) are unique plants containing 3-9% L-3,4-dihydroxyphenylalanine (L-DOPA). Here we investigated the effect of the administration of Mucuna beans on AD prevention by feeding triple-transgenic mice (3 × Tg-AD mice) with a diet containing Mucuna beans for 13 months. The levels of Aß oligomers and detergent-insoluble phosphorylated tau decreased in the brain of mice fed with Mucuna beans (Mucuna group) compared to those of the Control group. Aß accumulation and phosphorylated tau accumulation in the brain in the Mucuna group were also reduced. In addition, administration of Mucuna beans improved cognitive function. These results suggest that administration of Mucuna beans may have a preventive effect on AD development in 3 × Tg-AD mice.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Química Encefálica/efeitos dos fármacos , Mucuna/química , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/análise , Animais , Cognição/efeitos dos fármacos , Dieta/veterinária , Modelos Animais de Doenças , Feminino , Levodopa/análise , Camundongos Transgênicos , Proteínas tau/análise
17.
J Clin Invest ; 132(14)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35700043

RESUMO

Hepatic inflammation is culpable for the evolution of asymptomatic steatosis to nonalcoholic steatohepatitis (NASH). Hepatic inflammation results from abnormal macrophage activation. We found that FoxO1 links overnutrition to hepatic inflammation by regulating macrophage polarization and activation. FoxO1 was upregulated in hepatic macrophages, correlating with hepatic inflammation, steatosis, and fibrosis in mice and patients with NASH. Myeloid cell conditional FoxO1 knockout skewed macrophage polarization from proinflammatory M1 to the antiinflammatory M2 phenotype, accompanied by a reduction in macrophage infiltration in liver. These effects mitigated overnutrition-induced hepatic inflammation and insulin resistance, contributing to improved hepatic metabolism and increased energy expenditure in myeloid cell FoxO1-knockout mice on a high-fat diet. When fed a NASH-inducing diet, myeloid cell FoxO1-knockout mice were protected from developing NASH, culminating in a reduction in hepatic inflammation, steatosis, and fibrosis. Mechanistically, FoxO1 counteracts Stat6 to skew macrophage polarization from M2 toward the M1 signature to perpetuate hepatic inflammation in NASH. FoxO1 appears to be a pivotal mediator of macrophage activation in response to overnutrition and a therapeutic target for ameliorating hepatic inflammation to stem the disease progression from benign steatosis to NASH.


Assuntos
Proteína Forkhead Box O1 , Hepatopatia Gordurosa não Alcoólica , Hipernutrição , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Fibrose , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Inflamação/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hipernutrição/patologia
18.
J Biol Chem ; 285(33): 25545-53, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20530491

RESUMO

Retinol binding protein 4 (RBP4) is the transport protein that carries retinol in blood. RBP4 was described recently as a new adipokine that reduced insulin sensitivity. Mice lacking glucose transporter 4 (GLUT4) in adipocytes have enhanced Rbp4 gene expression; however, the molecular mechanism is unknown. We found a G4KA (GLUT4 knockdown-dependent transcriptional activation) element located approximately 1.3 kb upstream of the Rbp4 promoter. Mutations within the G4KA sequence significantly reduced expression of the Rbp4 promoter-reporter construct in G4KD-L1 (GLUT4 knockdown 3T3-L1) adipocyte cells. In a yeast one-hybrid screen of a G4KD-L1 cell cDNA library, using the G4KA element as bait, we identified subunits of the 20 S proteasome, PSMB1 and PSMA4, as binding partners. In chromatin immunoprecipitation assays, both subunits bound to the G4KA element; however, only PSMB1 was tightly bound in the GLUT4 knockdown model. PSMB1 RNA interference, but not PSMA4, significantly inhibited Rbp4 transcription. Nuclear transportation of PSMB1 was increased in G4KD-L1 cells. These results provide evidence for an exclusive proteasome subunit-related mechanism for transcriptional activation of RBP4 within a GLUT4 knockdown model.


Assuntos
Transportador de Glucose Tipo 4/fisiologia , Regiões Promotoras Genéticas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Plasmáticas de Ligação ao Retinol/genética , Ativação Transcricional/fisiologia , Células 3T3-L1 , Animais , Western Blotting , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Transportador de Glucose Tipo 4/genética , Lentivirus/genética , Camundongos , Interferência de RNA/fisiologia , Transcrição Gênica/genética , Transcrição Gênica/fisiologia , Ativação Transcricional/genética
19.
Biochem Biophys Res Commun ; 414(2): 287-91, 2011 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-21910974

RESUMO

AMP-activated protein kinase (AMPK) acts as an intracellular sensor to maintain the energy balance by phosphorylation of several downstream metabolic enzymes and certain transcription factors. We have identified a transcription factor named AREBP which is phosphorylated by AMPK in vitro. AREBP binds to the promoter element of PEPCK, a key enzyme of gluconeogenesis. Transient transfection experiments indicated AREBP repressed transcription of PEPCK gene in a phosphorylation dependent manner. To investigate the in vivo function of AREBP, we overexpressed AREBP in mice. Fasting-induced up-regulation of PEPCK gene expression was reduced by AICAR injection in AREBP mice. AICAR treatment repressed PEPCK gene expression in cultured hepatocytes derived from AREBP mice. Glucose output was reduced in AREBP mice after AICAR injection. Our results suggest AREBP is a key modulator of hepatic glucose production regulated by AMPK in vivo.


Assuntos
Glucose/biossíntese , Fígado/metabolismo , Proteínas Quinases/metabolismo , Fatores de Transcrição/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Humanos , Fígado/enzimologia , Camundongos , Camundongos Transgênicos , Regiões Promotoras Genéticas , Componente Amiloide P Sérico/genética , Fatores de Transcrição/genética
20.
J Am Chem Soc ; 132(28): 9746-52, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20586449

RESUMO

An anisotropic and inhomogeneous magnetic interaction (the average spin-spin interaction constant (-)J > 0) was observed in the various liquid crystalline (LC) phases of racemic and nonracemic all-organic radical LC compounds 1a and 1b. We discussed how the LC superstructures induced the magnetic interaction to operate in the LC phases in terms of spin-spin dipole and exchange interactions by means of VT-EPR spectroscopy. The magnitude of the magnetic interaction depended on the type of LC phase, or the superstructure. Furthermore, these radical LC droplets floating on water were commonly attracted to a permanent magnet and moved freely under the influence of this magnet, whereas the crystallized particles of the same compounds never responded to the magnet. The response of the LC droplets to the magnet also varied depending on the type of LC phase, that is, the extent of the magnetic interaction.

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