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1.
Curr Issues Mol Biol ; 44(11): 5474-5484, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36354682

RESUMO

Glucagon-like peptide-1 receptor agonist (GLP-1RA) has been clinically proven to protect endothelial function. Previously, we demonstrated that endothelial NO synthase (eNOS) was activated by high-density lipoprotein (HDL) via its scavenger receptor of the B class/human homologue of SR-BI, CD36 and LIMPII analogous-1(hSR-BI/CLA-1). Here, we investigated the effect of GLP-1RA and exendin-4 on the expression of hSR-BI/CLA-1 in HUVECs. Our results confirmed that GLP-1R was expressed in HUVECs by PCR and exendin-4 significantly enhanced HDL-induced eNOS activation. Next, exendin-4 increased the expression of hSR-BI/CLA-1 and a blockade of GLP-1R cancelled this effect. Further, the hSR-BI/CLA-1 transcriptional activity was enhanced by exendin-4, which was diminished by the inhibition of AMPK or dominant-negative AMPK-α-subunit. Moreover, AMPK was phosphorylated by the activation of GLP-1R. Next, ChIP assay demonstrated that exendin-4 increased the FoxO1-binding in the hSR-BI/CLA-1 promoter by upregulation of FoxO1. Mutation of FoxO1-binding or silencing of FoxO1 cancelled the effect of exendin-4 on hSR-BI/CLA-1 expression. Exendin-4 reduced FoxO1 phosphorylation and induced its nuclear accumulation, while this effect was altered by the blocking of GLP-1R or inhibition of AMPK pathway. In summary, our results proved that exendin-4 increased hSR-BI/CLA-1 expression via the AMPK/FoxO1 pathway to activate eNOS, providing a basic mechanism underlining the protective effect of GLP-1RA on endothelial function.

2.
Mol Hum Reprod ; 26(6): 441-451, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333783

RESUMO

Concentrations of 2-methoxyestradiol (2ME2), a principal metabolite of estradiol, are significantly lower in women with severe preeclampsia. Nitric oxide (NO) released by endothelial nitric oxide synthase (eNOS) plays an important role in regulating cardiovascular homeostasis. Importantly, high-density lipoprotein (HDL) stimulates eNOS activity via endothelial human scavenger receptor class B type I (hSR-BI/CLA-1). Here, we aimed to determine the effect of 2ME2 on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells (HUVECs). hSR-BI/CLA-1 expression was measured by real-time PCR, western blotting and reporter gene assays; eNOS activity was assessed by the measurement of eNOS phosphorylation. Both the mRNA and protein concentrations of hSR-BI/CLA-1 were significantly increased by 2ME2 in HUVECs. 2ME2 also dose-dependently increased the transcriptional activity of the hSR-BI/CLA-1 promoter. The effect of 2ME2 treatment on the promoter activity of hSR-BI/CLA-1 was abrogated by treatment with LY294002, a specific inhibitor of phosphatidylinositol 3-kinase, as was the increase in HDL-induced eNOS activation. Notably, constitutively active Akt increased the activity of the hSR-BI/CLA-1 promoter, whereas dominant-negative Akt abolished the effect of 2ME2 treatment on hSR-BI/CLA-1 promoter activity. The nuclear Sp1 protein concentration was significantly increased by exposure to 2ME2 and Sp1 overexpression increased the promoter activity of the hSR-BI/CLA gene. Furthermore, knockdown of Sp1 inhibited the effect of 2ME2 treatment on hSR-BI/CLA-1 protein expression. These results indicate that 2ME2 treatment increases HDL-dependent eNOS phosphorylation by upregulating endothelial hSR-BI/CLA-1 expression, suggesting that 2ME2 has a potential therapeutic value in the treatment of preeclampsia.


Assuntos
2-Metoxiestradiol/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , 2-Metoxiestradiol/uso terapêutico , Western Blotting , Imunoprecipitação da Cromatina , Feminino , Humanos , Lipoproteínas HDL/metabolismo , Óxido Nítrico/metabolismo , Pré-Eclâmpsia/tratamento farmacológico , Pré-Eclâmpsia/metabolismo , Gravidez
3.
J Lipid Res ; 59(10): 1906-1915, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30108153

RESUMO

In pancreatic ß cells, ABCA1, a 254 kDa membrane protein, affects cholesterol homeostasis and insulin secretion. Angiotensin II, as the main effector of the renin-angiotensin system, decreases glucose-stimulated insulin secretion (GSIS). We examined the effect of angiotensin II on ABCA1 expression in primary pancreatic islets and INS-1 cells. Angiotensin II decreased ABCA1 protein and mRNA; angiotensin II type 1 receptor (AT1R) blockade rescued this ABCA1 repression. In parallel, angiotensin II suppressed the promoter activity of ABCA1, an effect that was abrogated by PD98095, a specific inhibitor of MAPK kinase (MEK). LXR enhanced ABCA1 promoter activity, and angiotensin II decreased the nuclear abundance of LXR protein. On a chromatin immunoprecipitation assay, LXR mediated the transcription of ABCA1 by directly binding to its promoter. Mutation of the LXR binding site on the ABCA1 promoter cancelled the effect of angiotensin II. Furthermore, angiotensin II induced cholesterol accumulation and impaired GSIS; inhibition of AT1R or MEK pathway reversed these effects. In summary, our study showed that angiotensin II suppressed ABCA1 expression in pancreatic islets and INS-1 cells, indicating that angiotensin II may influence GSIS by regulating ABCA1 expression. Additional research may address therapeutic needs in diseases such as diabetes mellitus.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Angiotensina II/farmacologia , Colesterol/metabolismo , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Animais , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células Secretoras de Insulina/citologia , Receptores X do Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ratos , Transcrição Gênica/efeitos dos fármacos
4.
Am J Physiol Endocrinol Metab ; 315(6): E1232-E1241, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30130150

RESUMO

Recently, several clinical studies have suggested that adult growth hormone (GH) deficiency that also has low concentration of IGF1 is associated with an increased prevalence of fatty liver (FL). ATP-binding cassette transporter A1 (ABCA1) is a pivotal regulator of lipid efflux from cells to apolipoproteins and plays an important role on formation of FL. In this study, we determined the effects of IGF1 on ABCA1 expression in GH-deficient mice to clarify its effects on FL. Western blotting, real-time PCR, and a luciferase assay were employed to examine the effect of IGF1. The binding of FoxO1 to the ABCA1 promoter was assessed by chromatin immunoprecipitation (ChIP) assay. Cholesterol accumulation was analyzed by Oil Red O stain and cholesterol content measurement. We confirmed that IGF1 upregulated the ABCA1 expression. The activity of a reporter construct containing the ABCA1 promoter was induced by IGF1, and this effect was blocked by LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). Constitutively active Akt stimulated the ABCA1 promoter activity, and a dominant-negative mutant of Akt or mutagenesis of the FoxO1 response element abolished the effect of IGF1. A ChIP assay indicated that FoxO1 mediated IGF1 transcriptional activity by directly binding to the ABCA1 promoter region. For in vivo experiments, we used an inhibitor for the GH receptor (Pegvisomant) to reduce the IGF1 level. A high-fat diet induced FL in mice (C57BL/6J) given Pegvisomant treatment. IGF1 treatment stimulated ABCA1 expression to improve cholesterol accumulation in these mice. These results show that the PI3K/Akt/FoxO1 pathway contributes to the regulation of ABCA1 expression in response to IGF1 stimulation that suppressed FL in GH-deficient mice.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Colesterol/metabolismo , Nanismo Hipofisário/metabolismo , Fígado Gorduroso/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Fígado/metabolismo , Animais , Dieta Hiperlipídica , Proteína Forkhead Box O1/metabolismo , Células Hep G2 , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/farmacologia , Humanos , Fígado/efeitos dos fármacos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
Int J Urol ; 24(2): 162-165, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28012446

RESUMO

Insulin-like growth factor 2 is overexpressed in various cancers, and is associated with a poor prognosis. Also, it is known that insulin-like growth factor 2 is an etiology of non-islet cell tumor hypoglycemia. In this report, we describe a case of unexpected hypoglycemia caused by a dedifferentiated liposarcoma producing insulin-like growth factor 2. A large mass in the retroperitoneum was detected in a 61-year-old man who complained of appetite loss. Despite having no history of diabetes mellitus, hypoglycemia suddenly occurred after admission, but oral glucose therapy was ineffective. After total parenteral nutrition, tumor resection was attempted, but failed as a result of rigid adhesion to the surrounding organs. The patient died of the disease 21 days after surgery. Pathological diagnosis at autopsy revealed dedifferentiated liposarcoma, and immunohistochemical staining showed that the tumor excreted insulin-like growth factor 2. The possibility of an insulin-like growth factor 2-producing tumor should be taken into consideration when we encounter a patient with spontaneous hypoglycemia resistant to glucose substitution therapy.


Assuntos
Hipoglicemia/etiologia , Fator de Crescimento Insulin-Like II/metabolismo , Lipossarcoma/patologia , Neoplasias Retroperitoneais/patologia , Espaço Retroperitoneal/patologia , Humanos , Hipoglicemia/metabolismo , Fator de Crescimento Insulin-Like II/análise , Lipossarcoma/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neoplasias Retroperitoneais/diagnóstico por imagem , Espaço Retroperitoneal/diagnóstico por imagem
6.
Mol Biol Evol ; 30(3): 613-26, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23171859

RESUMO

MicroRNAs (miRNAs) are short, noncoding RNAs that modulate genes posttranscriptionally. Frequent gains and losses of miRNA genes have been reported to occur during evolution. However, little is known systematically about the periods of evolutionary origin of the present miRNA gene repertoire of an extant mammalian species. Thus, in this study, we estimated the evolutionary periods during which each of 1,433 present human miRNA genes originated within 15 periods, from human to platypus-human common ancestral branch and a class "conserved beyond theria," primarily using multiple genome alignments of 38 species, plus the pairwise genome alignments of five species. The results showed two peak periods in which the human miRNA genes originated at significantly accelerated rates. The most accelerated rate appeared in the period of the initial phase of hominoid lineage, and the second appeared shortly before Laurasiatherian divergence. Approximately 53% of the present human miRNA genes have originated within the simian lineage to human. In particular, approximately 28% originated within the hominoid lineage. The early phase of placental mammal radiation comprises approximately 28%, while no more than 15% of human miRNAs have been conserved beyond placental mammals. We also clearly showed a general trend, in which the miRNA expression level decreases as the miRNA becomes younger. Intriguingly, amid this decreasing trend of expression, we found one significant rise in the expression level that corresponded to the initial phase of the hominoid lineage, suggesting that increased functional acquisitions of miRNAs originated at this particular period.


Assuntos
Evolução Molecular , Hominidae/genética , MicroRNAs/genética , Modelos Genéticos , Animais , Cromossomos Humanos , Simulação por Computador , Expressão Gênica , Especiação Genética , Genoma , Humanos , Mamíferos/genética , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Família Multigênica
7.
Clin Exp Hypertens ; 35(5): 308-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22954233

RESUMO

Although increased oxidative stress is known to be associated with worsened cardiac function in chronic heart failure, consensus is still lacking regarding the association between oxidative stress and cardiac function in hypertensive patients without overt heart disease. This study aimed to evaluate the association between oxidative stress assessed by urinary 8-hydroxydeoxyguanosine (8-OHdG) and cardiac function in hypertensive patients without overt heart disease. We enrolled a total of 80 hypertensive patients (70 ± 11 y) who had been taking antihypertensive medications for at least 1 year. Urinary 8-OHdG levels were measured by an immunochromatographic assay (ICR-001, Selista Inc., Tokyo, Japan). Echocardiography was performed to assess the left ventricular (LV) diastolic function by measuring early diastolic mitral annular velocity (e') and the ratio of early transmitral flow velocity (E) to e' (E/e'). Urinary 8-OHdG was correlated with E/e' (r = 0.346, P = .002), e' (r = -0.310, P = .005), and HbA1c (r = 0.276, P = .013). Multiple linear regression analysis revealed that only e' (ß = -0.343, P = .004) was an independent determinant of urinary 8-OHdG. In conclusion, decreased e' is independently associated with elevated urinary 8-OHdG, a marker of oxidative stress, in hypertensive patients. Therefore, an elevated urinary 8-OHdG level may be useful in detecting subclinical LV diastolic dysfunction in hypertensive patients without overt heart disease.


Assuntos
Desoxiguanosina/análogos & derivados , Coração/fisiologia , Hipertensão/fisiopatologia , Estresse Oxidativo/fisiologia , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Biomarcadores/urina , Estudos Transversais , Desoxiguanosina/urina , Ecocardiografia , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/fisiologia
8.
Nutrients ; 15(12)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37375710

RESUMO

High sugar consumption increases the risk of diabetes, obesity, and cardiovascular diseases. Regarding the diet of patients with diabetes, artificial sweeteners are considered a safe alternative to sugar; however, there is also a risk that artificial sweeteners exacerbate glucose metabolism. D-allulose (C-3 isomer of d-fructose), which is a rare sugar, has been reported to have antidiabetic and antiobesity effects. In this study, the efficacy of a diabetic diet containing D-allulose was investigated in patients with type 2 diabetes using an intermittently scanned continuous glucose monitoring system (isCGM). This study was a validated, prospective, single-blind, randomized, crossover comparative study. Comparison of peak postprandial blood glucose (PPG) levels after consumption of a standard diabetic diet and a diabetic diet containing 8.5 g of D-allulose was the primary endpoint. A D-allulose-containing diabetic diet improved PPG levels in type two diabetes patients compared with a strictly energy-controlled diabetic diet. The results also showed a protective effect on endogenous pancreatic insulin secretory capacity owing to reduced insulin requirement. In patients with type two diabetes mellitus, diabetic diets containing 8.5 g D-allulose were effective in improving PPG levels.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Dieta para Diabéticos , Estudos Cross-Over , Projetos Piloto , Açúcares , Glicemia/metabolismo , Método Simples-Cego , Automonitorização da Glicemia , Estudos Prospectivos , Frutose/efeitos adversos , Edulcorantes , Insulina
9.
Mol Biol Evol ; 28(1): 639-46, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20805189

RESUMO

Transcription factors (TFs) and microRNAs (miRNAs) comprise two major layers of gene regulatory networks (GRNs). TFs and miRNAs function coordinately, but they have distinct molecular mechanisms and evolutionary backgrounds. Therefore, we aimed to systematically reveal the difference in contribution between TF and miRNA networks to the evolution of their coordinated regulations by focusing on composite feedforward circuits (cFFCs) that each comprises a TF and an miRNA. We compiled 124,736 human-mouse conserved TF regulatory connections and 34,298 conserved miRNA regulatory connections into two distinct connection matrices. To differentially assess the contributions to cFFC formation of TFs and miRNAs, we randomized one matrix and kept the other unchanged and subsequently examined the number of cFFCs, the number of cFFC-targeted genes, and the redundancy formed by cFFCs in comparison with those of the real GRNs. Because the matrices represent selectively constrained networks, if selection has been operating on the networks for or against cFFC formation, the values of cFFC network properties would deviate significantly from the expectation of the randomized networks. As the cFFC includes both TF and miRNA connections, the partial randomizations indicate the extent of influence of selection on cFFC formation differentially between TF and miRNA networks. Thus, we adopted the deviation of each cFFC network property value as a measure to estimate the extent of influence of selection on cFFCs and to compare the contribution between TF and miRNA networks. We found that miRNA regulatory networks changed their configuration such that they conformed to the stable TF regulatory networks with an increased circuit redundancy and a marked reduction in the repertoire of cFFC-targeted genes. We also revealed that this redundancy-adding role is preferentially attributable to miRNA network alterations. The results indicate that the redundancy-adding role might serve as a niche for many miRNA connections to survive, avoiding conflicts with the stable TF regulatory networks.


Assuntos
Regulação da Expressão Gênica , Redes Reguladoras de Genes , MicroRNAs/genética , Fatores de Transcrição/genética , Regiões 3' não Traduzidas , Animais , Bases de Dados Genéticas , Humanos , Camundongos , MicroRNAs/metabolismo , Fatores de Transcrição/metabolismo
10.
Rinsho Byori ; 60(11): 1081-6, 2012 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-23383578

RESUMO

Coronary artery disease (CAD) is a major public heath burden in many countries. HDL plays a critical role in cholesterol metabolism, so called reverse cholesterol transport (RCT). In RTC, HDL particles shuttle cholesterol from extra-hepatic tissues to the liver for excretion. Thus, enhanced RCT lowers total body cholesterol and thereby reduces the risk of developing CAD. We reported that human homologue of scavenger receptor of the class BI/CLA-1 (hSR-BI/CLA-1), like mouse SR-BI, functioned as a receptor for HDL. Hepatic hSR-BI/CLA-1 stimulates RCT, because it increases the hepatic uptake of free cholesterol from HDL. ABCA1 is a pivotal regulator of lipid efflux from cells to HDL particles, and plays an important role in RCT. Hyperglycemia is one of the risk factors for atherosclerosis. We showed that high glucose inactivated RCT via the inhibition of both hSR-BI/CLA-1 and ABCA1 expression. On the other hand, recent studies demonstrated that HDL binding to SR-BI activates eNOS, with the generation of nitric oxide, which may contribute to the positive cardiovascular effects. Treatment with angiotensin II reduced HDL-HDL-dependent eNOS activation via hSR-BI/CLA-1 expression, resulting in the progression of atherosclerosis. In conclusion, we demonstrate some mechanisms by which HDL is atheroprotective.


Assuntos
HDL-Colesterol/metabolismo , Estilo de Vida , Glicemia/metabolismo , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores Depuradores/metabolismo
11.
Nutrients ; 14(2)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35057469

RESUMO

ATP-binding cassette transporter A1 (ABCA1) is a key regulator of lipid efflux, and the absence of ABCA1 induces hepatic lipid accumulation, which is one of the major causes of fatty liver. 2-Methoxyestradiol (2-ME2) has been demonstrated to protect against fatty liver. In this study, we investigated the effects of 2-ME2 on the hepatic lipid content and ABCA1 expression. We found that 2-ME2 dose-dependently increased ABCA1 expression, and therefore, the lipid content was significantly decreased in HepG2 cells. 2-ME2 enhanced the ABCA1 promoter activity; however, this effect was reduced after the inhibition of the PI3K pathway. The overexpression of Akt or p110 induced ABCA1 promoter activity, while dominant-negative Akt diminished the ability of 2-ME2 on ABCA1 promoter activity. Further, 2-ME2 stimulated the rapid phosphorylation of Akt and FoxO1 and reduced the nuclear accumulation of FoxO1. Chromatin immunoprecipitation confirmed that FoxO1 bonded to the ABCA1 promoter region. The binding was reduced by 2-ME2, which facilitated ABCA1 gene transcription. Furthermore, mutating FoxO1-binding sites in the ABCA1 promoter region or treatment with FoxO1-specific siRNA disrupted the effect of 2-ME2 on ABCA1 expression. All of our results demonstrated that 2-ME2 might upregulate ABCA1 expression via the PI3K/Akt/FoxO1 pathway, which thus reduces the lipid content in hepatocytes.


Assuntos
2-Metoxiestradiol/farmacologia , Transportador 1 de Cassete de Ligação de ATP/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado Gorduroso/metabolismo , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
J Mol Endocrinol ; 68(2): 89-98, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-34845988

RESUMO

Adiponectin (APN) is an adipokine that protects against diabetes and atherosclerosis. High-density lipoprotein (HDL) mediates reverse cholesterol transport, which also protects against atherosclerosis. In this process, the human homolog of the B class type I scavenger receptor (SR-BI/CLA-1) facilitates the cellular uptake of cholesterol from HDL. The level of circulating APN is positively correlated with the serum level of HDL-cholesterol. In this study, we investigated whether HDL stimulates the gene expression of APN through the Ca2+/calmodulin (CaM)-dependent protein kinase IV (CaMKIV) cascade. APN expression was examined using real-time PCR and western blot analysis in 3T3-L1 cells incubated with HDL. CaMKIV activity was assessed by the detection of activation loop phosphorylation (at Thr196 residue), and the effect of the constitutively active form, CaMKIVc, on APN promoter activity was investigated. Our results showed that HDL stimulated APN gene expression via hSR-BI/CLA-1. Furthermore, we explored the signaling pathways by which HDL stimulated APN expression in 3T3-L1 cells. The stimulation of APN gene expression by HDL appears to be mediated by CaMKK, as STO-609, a specific inhibitor of CaMKK2, prevents this effect. We revealed that CaMKIVc increased APN gene transcriptional activity, and the CaMKIV-dominant negative mutant blocked the effect of HDL on APN promoter activity. Finally, knockdown of hSR-BI/CLA-1 also canceled the effect of HDL on APN gene expression. These results suggest that HDL has an important role to improve the function of adipocytes by activating hSR-BI/CLA-1, and CaMKK/CaMKIV pathway is conceivable as one of the signaling pathways of this activation mechanism.


Assuntos
Adiponectina , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina , Lipoproteínas HDL , Células 3T3-L1 , Adiponectina/genética , Adiponectina/metabolismo , Animais , Antígenos CD36/metabolismo , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/genética , Quinase da Proteína Quinase Dependente de Cálcio-Calmodulina/metabolismo , Expressão Gênica , Lipoproteínas HDL/metabolismo , Camundongos , Fosforilação
13.
Diabetol Metab Syndr ; 14(1): 86, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729673

RESUMO

BACKGROUND: During Ramadan fasting, postprandial hyperglycemia is commonly observed after iftar (break of fast at sunset) meal. D-allulose is a rare sugar and is reported to have several health benefits, including the suppression of increase in postprandial glucose levels. This study investigates whether D-allulose (a C-3 epimer of D-fructose) improves the postprandial glucose in patients with type 2 diabetes mellitus (T2DM) during Ramadan. METHODS: This was a pilot, prospective single-arm study design that was conducted for 10 consecutive days; 5 days of control and 5 days of consumption. The primary outcome was postprandial peak glucose levels. During the consumption period, 8.5 g of D-allulose was consumed by the participants before iftar meal. Postprandial glucose was measured using a continuous glucose monitoring system. RESULTS: A total of 12 participants completed the study. Significant lower (p < 0.01) postprandial glucose values and the glucose incremental area under the curve (iAUC) were observed from 0 to 180 min during the consumption period compared to the control period. The consumption period demonstrated significantly higher percentages of time in which glucose values were found in the target range (p = 0.0032), and when the glucose levels above the target range were reduced (p = 0.0015). CONCLUSIONS: The supplementation with D-allulose has the potential to improve postprandial hyperglycemia in patients with T2DM after iftar during Ramadan. Further studies are needed to confirm these findings. Trial registration ClinicalTrials.gov NCT05071950. Retrospectively registered, 8 October 2021.

14.
Diabetes Metab Syndr ; 16(11): 102655, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36323181

RESUMO

BACKGROUND AND AIMS: To assess the level of diabetes knowledge and its association with diabetes self-management practices during Ramadan fasting among patients with type 2 diabetes (T2D). METHODS: A cross-sectional study was conducted involving a sample of Malaysian patients with T2D. Patients aged 18 years and above, and attending an outpatient diabetic unit of a government hospital were recruited between February and April 2021. A self-administered questionnaire was utilized to assess diabetes knowledge and diabetes self-management practices. RESULTS: A total of 306 participants completed the questionnaire. Most of them were females (54.2%) and above 55 years old (75.1%). Resultantly, knowledge of diabetes was considered average among 52% of the participants. Only 9.5% of them avoided the consumption of sweet foods during iftar. Practicing late suhoor (p = 0.012) and self-monitoring of blood glucose (SMBG) (p = 0.026) during Ramadan were significantly associated with a better diabetes knowledge score. Education level (p = 0.000), working status (p = 0.030), and monthly income (p = 0.000) were significantly associated with participants' knowledge level of diabetes. A higher proportion (72.2%) of the participants completed fasting for a month during Ramadan 2020. Meanwhile, hypoglycemia was the main reason (38.8%) for incomplete fasting. CONCLUSIONS: These findings reflect the need to improve patients' knowledge of diabetes and diabetes self-management practices, especially during Ramadan. Such objectives could be achieved by considering the associated factors identified in this study.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Feminino , Humanos , Pessoa de Meia-Idade , Masculino , Jejum , Islamismo , Estudos Transversais , Malásia/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde
15.
BMC Genomics ; 12: 228, 2011 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-21569329

RESUMO

BACKGROUND: The transcriptional regulatory network is considered to be built from a set of circuit patterns called network motifs. Experimental studies have provided instances where a feedforward circuit (FFC) appears with modification of autoregulation, but little is known systematically about such autoregulation-integrated FFCs. Therefore, we aimed to examine whether the autoregulation-integrated FFC is a network motif relevant to describing the human transcriptional regulatory systems, and explored the relationship of such network motifs with biological functions. RESULTS: Based on human-mouse evolutionarily conserved transcription factor binding sites (TFBSs) in 76600 conserved blocks for 5169 genes, we compiled the human transcriptional connections into a matrix, and examined the number of FFC appearances in comparison with randomized networks. The results revealed that the configuration of autoregulation integrated in the FFC critically affects the abundance or avoidance of FFC appearances. In particular, an FFC comprising two repressors that are both autoregulated was revealed as a significant network motif, which we termed the double-autoregulation FFC (DAR-FFC). Interestingly, this network motif preferentially constitutes effecter transcriptional circuits with functions in cell-cell signaling and multicellular organization, and is particularly related to nervous system development. CONCLUSIONS: We have revealed that the configuration of autoregulation integrated in the FFCs is a critical factor for abundance or avoidance of the appearance of the FFCs. In particular, we have identified the DAR-FFC as a distinctive integrated network motif endowed with properties that are indispensable for forming the transcriptional regulatory circuits involved in multicellular organization and nervous system development. This is the first report showing that the DAR-FFC is a significant network motif.


Assuntos
Biologia Computacional , Redes Reguladoras de Genes/genética , Sistema Nervoso/crescimento & desenvolvimento , Sistema Nervoso/metabolismo , Animais , Comunicação Celular/genética , Humanos , Camundongos , Proteínas Repressoras/metabolismo
17.
Nutrients ; 13(9)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34578896

RESUMO

Impaired insulin secretion is one of the main causes of type 2 diabetes. Cholesterol accumulation-induced lipotoxicity contributes to impaired insulin secretion in pancreatic beta cells. However, the detailed mechanism in this process remains unclear. In this study, we proved that oxidized low-density lipoprotein (OxLDL) reduced insulin content, decreased PDX-1 expression, and impaired glucose-stimulated insulin secretion (GSIS) in INS-1 cells, which were rescued by addition of high-density lipoprotein (HDL). OxLDL receptors and cholesterol content were increased by OxLDL. Consistently, OxLDL suppressed cholesterol transporter ABCA1 expression and transcription in a dose-dependent and time-dependent manner. Inhibition of MEK by its specific inhibitor, PD98059, altered the effect of OxLDL on ABCA1 transcription and activation of ERK. Next, chromatin immunoprecipitation assay demonstrated that liver X receptor (LXR) could directly bind to ABCA1 promoter and this binding was inhibited by OxLDL. Furthermore, OxLDL decreased the nuclear LXR expression, which was prevented by HDL. LXR-enhanced ABCA1 transcription was suppressed by OxLDL, and the effect was cancelled by mutation of the LXR-binding sites. In summary, our study shows that OxLDL down-regulates ABCA1 expression by MEK/ERK/LXR pathway, leading to cholesterol accumulation in INS-1 cells, which may result in impaired insulin synthesis and GSIS.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/genética , Regulação para Baixo/genética , Insulinoma/genética , Lipoproteínas LDL/genética , Receptores X do Fígado/genética , Sistema de Sinalização das MAP Quinases/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Células Cultivadas , Regulação para Baixo/fisiologia , Expressão Gênica/genética , Humanos , Insulinoma/metabolismo , Lipoproteínas LDL/metabolismo , Receptores X do Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Ratos
18.
J Med Case Rep ; 15(1): 214, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33892782

RESUMO

BACKGROUND: Immune checkpoint inhibitors have recently become widely used for the management of advanced cancer patients. During the development of immune checkpoint inhibitors (ICPIs), it was quickly recognized that they are associated with autoimmune or autoinflammatory side effects. These toxicities are known as immune-related adverse events (irAEs): common endocrine irAEs include hypophysitis and thyroid dysfunction, and uncommon irAEs include type 1 diabetes mellitus (T1DM). CASE PRESENTATION: A 62-year-old Japanese man with metastatic renal cell carcinoma was treated with sunitinib followed by the 10th cycle of treatment with the ICPI nivolumab. He had already had thyroiditis and hypophysitis due to these anti-cancer drugs. On admission, he showed an extremely elevated plasma glucose level (601 mg/dl) and a low C-peptide level, and was diagnosed with acute T1DM. The patient was treated with intravenous fluid infusion and continuous insulin infusion. On the second day, he was switched to multiple daily injections of insulin therapy. Since these treatments, his blood glucose levels have been stable and he has been treated with an additional 10 ICPI treatments for renal cell carcinoma for over a year. CONCLUSIONS: Treatment with ICPIs is expected to increase in the future. There may be cases in which their use for cancer treatment is inevitable despite the side effects. As long as treatment with ICPI continues, multiple side effects can be expected in some cases. It is important to carefully observe the side effects that occur during ICPI treatment and to provide appropriate treatment for each side effect.


Assuntos
Carcinoma de Células Renais , Diabetes Mellitus Tipo 1 , Hipofisite , Neoplasias Renais , Carcinoma de Células Renais/tratamento farmacológico , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Hipofisite/induzido quimicamente , Neoplasias Renais/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nivolumabe/efeitos adversos
19.
J Mol Endocrinol ; 66(3): 223-231, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33638940

RESUMO

Vascular complications are the main cause of morbidity and mortality in diabetic patients, and advanced glycation end products (AGEs) play a critical role in promoting diabetic vascular dysfunction. The human homolog of scavenger receptor class B type I (SR-BI), CD36, and LIMPII analog-1 (hSR-BI/CLA-1) facilitates the cellular uptake of cholesterol from HDL. In endothelial cells, HDL activates endothelial nitric oxide synthase (eNOS) via hSR-BI/CLA-1. In this study, we elucidated the effects of AGEs on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells (HUVECs). HSR-BI/CLA-1 expression was examined by real-time PCR, western blot analysis, and reporter gene assay in HUVECs incubated with AGEs. eNOS activity was assessed by detecting the phosphorylation (Ser 1179) of eNOS. Our results showed that AGEs decreased the endogenous expression of hSR-BI/CLA-1. AGEs also inhibited the activity of the hSR-BI/CLA-1 promoter and its mRNA expression via receptor RAGE. We identified the binding site for Smad1 on the hSR-BI/CLA-1 promoter: Smad1 bound to its promoter. AGE treatment stimulated the transcriptional activity of Smad1, and mutation of the Smad1 binding site inhibited the effect of AGEs on the hSR-BI/CLA-1 promoter. HDL-treatment enhanced the phosphorylation of eNOS at Ser 1179, but pretreatment with AGEs inhibited the phosphorylation of eNOS Ser 1179. These results suggested that AGEs downregulate the expression of the endothelial hSR-BI/CLA-1 via the Smad1 pathway, which may be a therapeutic target for diabetic endothelial dysfunction.


Assuntos
Antígenos CD36/genética , Regulação da Expressão Gênica , Produtos Finais de Glicação Avançada/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteína Smad1/metabolismo , Sequência de Bases , Antígenos CD36/metabolismo , DNA/genética , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Regiões Promotoras Genéticas , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transcrição Gênica/efeitos dos fármacos
20.
Intern Med ; 60(7): 1047-1053, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33162471

RESUMO

It is quite rare that Cushing's disease shows acromegaly, and no pharmacotherapy has yet been discussed. A 21-year-old woman was diagnosed with Cushing's disease and underwent trans-sphenoidal surgery. Five years later, she was diagnosed with recurrent Cushing's disease and biochemical acromegaly because of elevated levels of serum growth hormone (GH), plasma insulin-like growth factor-1, plasma adrenocorticotropic hormone (ACTH), and the 24-hour urinary excretion of free cortisol. After treatment initiation with pasireotide-long-acting release (LAR), both the ACTH and GH declined. Our case is the first to show the efficacy of pasireotide-LAR in controlling both Cushing's disease and acromegaly.


Assuntos
Acromegalia , Hipersecreção Hipofisária de ACTH , Acromegalia/complicações , Acromegalia/tratamento farmacológico , Hormônio Adrenocorticotrópico , Adulto , Feminino , Humanos , Hipersecreção Hipofisária de ACTH/complicações , Hipersecreção Hipofisária de ACTH/tratamento farmacológico , Somatostatina/análogos & derivados , Adulto Jovem
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