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1.
Res Sq ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585822

RESUMO

Behavioral adaptations to environmental threats are crucial for survival and necessitate rapid deployment of energy reserves. The amygdala coordinates behavioral adaptations to threats, but little is known about its involvement in underpinning metabolic adaptations. Here, we show that acute stress activates medial amygdala (MeA) neurons that innervate the ventromedial hypothalamus (MeAVMH neurons), which precipitates hyperglycemia and hypophagia. The glycemic actions of MeAVMH neurons occur independent of adrenal or pancreatic glucoregulatory hormones. Instead, using whole-body virus tracing, we identify a polysynaptic connection from MeA to the liver, which promotes the rapid synthesis of glucose by hepatic gluconeogenesis. Repeated stress exposure disrupts MeA control of blood glucose and appetite, resulting in diabetes-like dysregulation of glucose homeostasis and weight gain. Our findings reveal a novel amygdala-liver axis that regulates rapid glycemic adaptations to stress and links recurrent stress to metabolic dysfunction.

2.
Cell Metab ; 36(4): 793-807.e5, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38378001

RESUMO

Aging is underpinned by pronounced metabolic decline; however, the drivers remain obscure. Here, we report that IgG accumulates during aging, particularly in white adipose tissue (WAT), to impair adipose tissue function and metabolic health. Caloric restriction (CR) decreases IgG accumulation in WAT, whereas replenishing IgG counteracts CR's metabolic benefits. IgG activates macrophages via Ras signaling and consequently induces fibrosis in WAT through the TGF-ß/SMAD pathway. Consistently, B cell null mice are protected from aging-associated WAT fibrosis, inflammation, and insulin resistance, unless exposed to IgG. Conditional ablation of the IgG recycling receptor, neonatal Fc receptor (FcRn), in macrophages prevents IgG accumulation in aging, resulting in prolonged healthspan and lifespan. Further, targeting FcRn by antisense oligonucleotide restores WAT integrity and metabolic health in aged mice. These findings pinpoint IgG as a hidden culprit in aging and enlighten a novel strategy to rejuvenate metabolic health.


Assuntos
Tecido Adiposo , Envelhecimento , Camundongos , Animais , Envelhecimento/metabolismo , Tecido Adiposo Branco/metabolismo , Camundongos Knockout , Fibrose , Imunoglobulina G
3.
China CDC Wkly ; 6(2): 30-35, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38250700

RESUMO

What is already known about this topic?: Studies have extensively documented the separate and independent effects of extreme temperature and ozone on morbidity and mortality associated with respiratory and circulatory diseases. What is added by this report?: The study revealed a significant association between elevated temperature, ozone pollution, and the combined effect of high temperature and ozone pollution with an increased risk of all-cause medical emergency calls (MECs) and MECs specifically related to neurological diseases. What are the implications for public health practice?: Interventional measures should be implemented to mitigate exposure to high temperatures and ozone levels. Specifically, during the warm season, it is crucial for relevant authorities to focus on disseminating scientific information regarding the health impacts of elevated temperatures and ozone pollution. Additionally, timely public health advisories should be issued to alert the public effectively.

4.
bioRxiv ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38293175

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH) can progress to cirrhosis and liver cancer. There are no approved medical therapies to prevent or reverse disease progression. Fructose and its metabolism in the liver play integral roles in MASH pathogenesis and progression. Here we focus on mannose, a simple sugar, which dampens hepatic stellate cell activation and mitigates alcoholic liver disease in vitro and in vivo . In the well-validated FAT-MASH murine model, oral mannose supplementation improved both liver steatosis and fibrosis at low and high doses, whether administered either at the onset of the model ("Prevention") or at week 6 of the 12-week MASH regimen ("Reversal"). The in vivo anti-fibrotic effects of mannose supplementation were validated in a second model of carbon tetrachloride-induced liver fibrosis. In vitro human and mouse primary hepatocytes revealed that the anti-steatotic effects of mannose are dependent on the presence of fructose, which attenuates expression of ketohexokinase (KHK), the main enzyme in fructolysis. KHK is decreased with mannose supplementation in vivo and in vitro, and overexpression of KHK abrogated the anti-steatotic effects of mannose. Our study identifies mannose as a simple, novel therapeutic candidate for MASH that mitigates metabolic dysregulation and exerts anti-fibrotic effects.

5.
J Clin Transl Hepatol ; 11(5): 1184-1191, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37577233

RESUMO

Hepatocellular carcinoma (HCC) is a common tumor. Although the diagnosis and treatment of HCC have made great progress, the overall prognosis remains poor. As the core component of artificial intelligence, machine learning (ML) has developed rapidly in the past decade. In particular, ML has become widely used in the medical field, and it has helped in the diagnosis and treatment of cancer. Different algorithms of ML have different roles in diagnosis, treatment, and prognosis. This article reviews recent research, explains the application of different ML models in HCC, and provides suggestions for follow-up research.

6.
Int J Biol Macromol ; 241: 124493, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37086771

RESUMO

The abuse of chrome tanning agent in leather processing has caused great harm to human health and the natural environment. We use tremella polysaccharides (TP), lentinan (LNT) and konjac gum (KG) as raw materials, and sodium periodate as oxidant to prepare the corresponding polysaccharide tanning agent. Tremella polysaccharide was selected as the best tanning agent according to the shrinkage temperature, and the subsequent experiments were carried out. Tremella polysaccharide (TP) as raw material and sodium periodate as an oxidant, dialdehyde tremella polysaccharide (DTP) was prepared and applied in leather tanning. The effects of different oxidation conditions (sodium periodate dosage, temperature, pH, and reaction time) on the shrinkage temperature of DTP tanned leather were studied. The change of shrinkage temperature showed that the dosage of sodium periodate had the greatest influence on the shrinkage temperature. Therefore, the effects of different dosage of sodium periodate on the aldehyde content and molecular weight of DTP were investigated, including the analysis of physical properties and microstructure of tanned leather. In general, the increase of sodium periodate dosage was found to increase the aldehyde content and reduce the molecular weight, which was more conducive to leather tanning.


Assuntos
Polissacarídeos , Curtume , Humanos , Aldeídos , Oxidantes , Cromo/análise
7.
Diabetol Int ; 14(1): 21-31, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36636157

RESUMO

Research on the etiology and treatment of diabetes has made substantial progress. As a result, several new classes of anti-diabetic drugs have been introduced in clinical practice. Nonetheless, the number of patients achieving glycemic control targets has not increased for the past 20 years. Two areas of unmet medical need are the restoration of insulin sensitivity and the reversal of pancreatic beta cell failure. In this review, we integrate research advances in transcriptional regulation of insulin action and pathophysiology of beta cell dedifferentiation with their potential impact on prospects of a durable "cure" for patients suffering from type 2 diabetes.

8.
Adv Sci (Weinh) ; 10(2): e2204190, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36394167

RESUMO

Systemic glucose metabolism and insulin activity oscillate in response to diurnal rhythms and nutrient availability with the necessary involvement of adipose tissue to maintain metabolic homeostasis. However, the adipose-intrinsic regulatory mechanism remains elusive. Here, the dynamics of PPARγ acetylation in adipose tissue are shown to orchestrate metabolic oscillation in daily rhythms. Acetylation of PPARγ displays a diurnal rhythm in young healthy mice, with the peak at zeitgeber time 0 (ZT0) and the trough at ZT18. This rhythmic pattern is deranged in pathological conditions such as obesity, aging, and circadian disruption. The adipocyte-specific acetylation-mimetic mutation of PPARγ K293Q (aKQ) restrains adipose plasticity during calorie restriction and diet-induced obesity, associated with proteolysis of a core circadian component BMAL1. Consistently, the rhythmicity in glucose tolerance and insulin sensitivity is altered in aKQ and the complementary PPARγ deacetylation-mimetic K268R/K293R (2KR) mouse models. Furthermore, the PPARγ acetylation-sensitive downstream target adipsin is revealed as a novel diurnal factor that destabilizes BMAL1 and mediates metabolic rhythms. These findings collectively signify that PPARγ acetylation is a hinge connecting adipose plasticity and metabolic rhythms, the two determinants of metabolic health.


Assuntos
Fatores de Transcrição ARNTL , PPAR gama , Camundongos , Animais , PPAR gama/genética , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Acetilação , Obesidade/metabolismo , Tecido Adiposo/metabolismo
9.
J Clin Invest ; 132(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36282594

RESUMO

As a highly regenerative organ, the intestine is a promising source for cellular reprogramming for replacing lost pancreatic ß cells in diabetes. Gut enterochromaffin cells can be converted to insulin-producing cells by forkhead box O1 (FoxO1) ablation, but their numbers are limited. In this study, we report that insulin-immunoreactive cells with Paneth/goblet cell features are present in human fetal intestine. Accordingly, lineage-tracing experiments show that, upon genetic or pharmacologic FoxO1 ablation, the Paneth/goblet lineage can also undergo conversion to the insulin lineage. We designed a screening platform in gut organoids to accurately quantitate ß-like cell reprogramming and fine-tune a combination treatment to increase the efficiency of the conversion process in mice and human adult intestinal organoids. We identified a triple blockade of FOXO1, Notch, and TGF-ß that, when tested in insulin-deficient streptozotocin (STZ) or NOD diabetic animals, resulted in near normalization of glucose levels, associated with the generation of intestinal insulin-producing cells. The findings illustrate a therapeutic approach for replacing insulin treatment in diabetes.


Assuntos
Diabetes Mellitus , Células Secretoras de Insulina , Humanos , Camundongos , Animais , Proteína Forkhead Box O1/genética , Fatores de Transcrição Forkhead/genética , Camundongos Endogâmicos NOD , Insulina/genética
10.
Sci Rep ; 12(1): 12330, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853969

RESUMO

The incidence of hepatocellular carcinoma (HCC) has increased in these years. DNA damage repair (DDR) pathway is required in response to DNA damage Gene mutations in DDR pathway play an important role in different stages of tumorigenesis and development. Based on the importance of DDR pathway in precision therapy of multiple cancers, we analyzed DDR gene mutations in Chinese patients with HCC. The results showed that (tumor mutation burden) TMB was significantly higher in HCC patients who carried somatic mutations in DDR than in non-carriers, and TMB in patients with DS, MMR mutations and DDR genes mutations such as RAD50, MLH1, MSH2, CHEK2 was significantly higher than that in wild-type patients. Based on the results of next-generation sequencing (NGS) testing, we are trying to provide clues for targeted therapy and provide feasible basis for PD-1/PD-L1 immune checkpoint inhibitor therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , China , Dano ao DNA/genética , Reparo do DNA/genética , Humanos , Neoplasias Hepáticas/genética , Mutação
11.
Sci Rep ; 12(1): 8670, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35606395

RESUMO

To establish a model based on inflammation index and tumor burden score (TBS) to predict recurrence of hepatocellular carcinoma (HCC) after liver resection. A retrospective study was performed on 217 patients who diagnosed HCC underwent liver resection at Xiangya Hospital Central South University from June 1, 2017 to June 1, 2019. According to the receiver operating characteristic (ROC) curve, the optimal cut-off value of inflammatory index and the TBS was determined by the Youden index. Prediction performance was compared by the area under the receiver operating characteristic curve (AUC). Cox regression analysis was used to determine the risk factors for the recurrence of HCC after liver resection. According to the independent risk factors of the patients, a prediction model for HCC was established based on inflammation index and tumor burden score (TBS).The prediction performance of the model was compared with single index (TBS group and NLR group) and traditional HCC stage models (TNM stage and BCLC stage). MLR = 0.39, NLR = 2.63, PLR = 134, SII = 428 and TBS = 8.06 are the optimal cut-off values. AUC of SII, PLR, NLR, MLR and TBS were 0.643, 0.642, 0.642, 0.618 and 0.724respectively. MVI (P = 0.005), satellite nodule (P = 0.017), BCLC B-C stage (P = 0.013), NLR > 2.63 (P = 0.013), TBS > 8.06 (P = 0.017) are independent risk factors for the recurrence of HCC after liver resection. According to this study, the optimal inflammatory index NLR combined with TBS was obtained. The AUC of NLR-TBS model was 0.762, not only better than NLR group (AUC = 0.630) and TBS group (AUC = 0.671), also better than traditional BCLC (AUC = 0.620) and TNM (AUC = 0.587) stage models. Interestingly, we found that NLR and TBS should be good prognostic factor for recurrence of HCC after liver resection. The NLR-TBS model based the best inflammatory index (NLR) and TBS have a better prediction performance and the prediction performance of NLR-TBS model not only better than NLR group and TBS group, but better than BCLC and TNM stage models.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Humanos , Inflamação/patologia , Neoplasias Hepáticas/patologia , Linfócitos/patologia , Neutrófilos/patologia , Prognóstico , Estudos Retrospectivos , Carga Tumoral
12.
Cell Metab ; 34(1): 158-170.e5, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34914893

RESUMO

Increased hepatic glucose production (HGP) contributes to hyperglycemia in type 2 diabetes. Hormonal regulation of this process is primarily, but not exclusively, mediated by the AKT-FoxO1 pathway. Here, we show that cAMP and dexamethasone regulate the high-mobility group superfamily member TOX4 to mediate HGP, independent of the insulin receptor/FoxO1 pathway. TOX4 inhibition decreases glucose production in primary hepatocytes and liver and increases glucose tolerance. Combined genetic ablation of TOX4 and FoxO1 in liver has additive effects on glucose tolerance and gluconeogenesis. Moreover, TOX4 ablation fails to reverse the metabolic derangement brought by insulin receptor knockout. TOX4 expression is increased in livers of patients with steatosis and diabetes and in diet-induced obese and db/db mice. In the latter two murine models, knockdown Tox4 decreases glycemia and improves glucose tolerance. We conclude that TOX4 is an insulin receptor-independent regulator of HGP and a candidate contributor to the pathophysiology of diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Glucose , Fígado , Proteínas de Neoplasias , Animais , Diabetes Mellitus Tipo 2/metabolismo , Proteína Forkhead Box O1/metabolismo , Gluconeogênese/genética , Glucose/metabolismo , Humanos , Insulina/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Receptor de Insulina/metabolismo
13.
Front Optoelectron ; 15(1): 1, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36637553

RESUMO

Optical directed logic (DL) is a novel logic operation scheme that employs electrical signals as operands to control the working states of optical switches to perform the logic functions. This review first provides an overview of the concept and working principle of DL. The developing trends of DL computing are then discussed in detail, including the fundamental optical DL gates, combinational optical DL operations, reconfigurable logic computing, low power optical logic computing, and programmable photonic network. The concluding remarks provide an outlook on the DL future development and its impacts in optical computing.

14.
Elife ; 102021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34155972

RESUMO

Background: Marrow adipose tissue (MAT) has been shown to be vital for regulating metabolism and maintaining skeletal homeostasis in the bone marrow (BM) niche. As a reflection of BM remodeling, MAT is highly responsive to nutrient fluctuations, hormonal changes, and metabolic disturbances such as obesity and diabetes mellitus. Expansion of MAT has also been strongly associated with bone loss in mice and humans. However, the regulation of BM plasticity remains poorly understood, as does the mechanism that links changes in marrow adiposity with bone remodeling. Methods: We studied deletion of Adipsin, and its downstream effector, C3, in C57BL/6 mice as well as the bone-protected PPARγ constitutive deacetylation 2KR mice to assess BM plasticity. The mice were challenged with thiazolidinedione treatment, calorie restriction, or aging to induce bone loss and MAT expansion. Analysis of bone mineral density and marrow adiposity was performed using a µCT scanner and by RNA analysis to assess adipocyte and osteoblast markers. For in vitro studies, primary bone marrow stromal cells were isolated and subjected to osteoblastogenic or adipogenic differentiation or chemical treatment followed by morphological and molecular analyses. Clinical data was obtained from samples of a previous clinical trial of fasting and high-calorie diet in healthy human volunteers. Results: We show that Adipsin is the most upregulated adipokine during MAT expansion in mice and humans in a PPARγ acetylation-dependent manner. Genetic ablation of Adipsin in mice specifically inhibited MAT expansion but not peripheral adipose depots, and improved bone mass during calorie restriction, thiazolidinedione treatment, and aging. These effects were mediated through its downstream effector, complement component C3, to prime common progenitor cells toward adipogenesis rather than osteoblastogenesis through inhibiting Wnt/ß-catenin signaling. Conclusions: Adipsin promotes new adipocyte formation and affects skeletal remodeling in the BM niche. Our study reveals a novel mechanism whereby the BM sustains its own plasticity through paracrine and endocrine actions of a unique adipokine. Funding: This work was supported by the National Institutes of Health T32DK007328 (NA), F31DK124926 (NA), R01DK121140 (JCL), R01AR068970 (BZ), R01AR071463 (BZ), R01DK112943 (LQ), R24DK092759 (CJR), and P01HL087123 (LQ).


Assuntos
Adiposidade , Medula Óssea/metabolismo , Fator D do Complemento/genética , Células-Tronco Mesenquimais/metabolismo , Animais , Fator D do Complemento/metabolismo , Feminino , Humanos , Masculino , Camundongos
15.
J Clin Invest ; 131(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33630762

RESUMO

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disorder caused by mutations in genes encoding components of the primary cilium and is characterized by hyperphagic obesity. To investigate the molecular basis of obesity in human BBS, we developed a cellular model of BBS using induced pluripotent stem cell-derived (iPSC-derived) hypothalamic arcuate-like neurons. BBS mutations BBS1M390R and BBS10C91fsX95 did not affect neuronal differentiation efficiency but caused morphological defects, including impaired neurite outgrowth and longer primary cilia. Single-cell RNA sequencing of BBS1M390R hypothalamic neurons identified several downregulated pathways, including insulin and cAMP signaling and axon guidance. Additional studies demonstrated that BBS1M390R and BBS10C91fsX95 mutations impaired insulin signaling in both human fibroblasts and iPSC-derived neurons. Overexpression of intact BBS10 fully restored insulin signaling by restoring insulin receptor tyrosine phosphorylation in BBS10C91fsX95 neurons. Moreover, mutations in BBS1 and BBS10 impaired leptin-mediated p-STAT3 activation in iPSC-derived hypothalamic neurons. Correction of the BBS mutation by CRISPR rescued leptin signaling. POMC expression and neuropeptide production were decreased in BBS1M390R and BBS10C91fsX95 iPSC-derived hypothalamic neurons. In the aggregate, these data provide insights into the anatomic and functional mechanisms by which components of the BBSome in CNS primary cilia mediate effects on energy homeostasis.


Assuntos
Síndrome de Bardet-Biedl/metabolismo , Chaperoninas/metabolismo , Hipotálamo/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação de Sentido Incorreto , Neurônios/metabolismo , Sistemas do Segundo Mensageiro , Substituição de Aminoácidos , Animais , Síndrome de Bardet-Biedl/genética , Chaperoninas/genética , AMP Cíclico/genética , AMP Cíclico/metabolismo , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/genética
16.
J Hepatol ; 73(2): 361-370, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32135178

RESUMO

BACKGROUND & AIMS: Obesity is a well-established risk factor for type 2 diabetes (T2D) and non-alcoholic steatohepatitis (NASH), but the underlying mechanisms remain incompletely understood. Herein, we aimed to identify novel pathogenic factors (and possible therapeutic targets) underlying metabolic dysfunction in the liver. METHODS: We applied a tandem quantitative proteomics strategy to enrich and identify transcription factors (TFs) induced in the obese liver. We used flow cytometry of liver cells to analyze the source of the induced TFs. We employed conditional knockout mice, shRNA, and small-molecule inhibitors to test the metabolic consequences of the induction of identified TFs. Finally, we validated mouse data in patient liver biopsies. RESULTS: We identified PU.1/SPI1, the master hematopoietic regulator, as one of the most upregulated TFs in livers from diet-induced obese (DIO) and genetically obese (db/db) mice. Targeting PU.1 in the whole liver, but not hepatocytes alone, significantly improved glucose homeostasis and suppressed liver inflammation. Consistently, treatment with the PU.1 inhibitor DB1976 markedly reduced inflammation and improved glucose homeostasis and dyslipidemia in DIO mice, and strongly suppressed glucose intolerance, liver steatosis, inflammation, and fibrosis in a dietary NASH mouse model. Furthermore, hepatic PU.1 expression was positively correlated with insulin resistance and inflammation in liver biopsies from patients. CONCLUSIONS: These data suggest that the elevated hematopoietic factor PU.1 promotes liver metabolic dysfunction, and may be a useful therapeutic target for obesity, insulin resistance/T2D, and NASH. LAY SUMMARY: Expression of the immune regulator PU.1 is increased in livers of obese mice and people. Blocking PU.1 improved glucose homeostasis, and reduced liver steatosis, inflammation and fibrosis in mouse models of non-alcoholic steatohepatitis. Inhibition of PU.1 is thus a potential therapeutic strategy for treating obesity-associated liver dysfunction and metabolic diseases.


Assuntos
Camundongos Obesos/metabolismo , Hepatopatia Gordurosa não Alcoólica , Proteínas Proto-Oncogênicas , Transativadores , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Hepatócitos/metabolismo , Humanos , Fígado/patologia , Camundongos , Camundongos Knockout , Terapia de Alvo Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/metabolismo , Transativadores/antagonistas & inibidores , Transativadores/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Regulação para Cima
17.
Diabetes ; 68(6): 1156-1167, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30936148

RESUMO

Hepatocyte glucose production is a complex process that integrates cell-autonomous mechanisms with cellular signaling, enzyme activity modulation, and gene transcription. Transcriptional mechanisms controlling glucose production are redundant and involve nuclear hormone receptors and unliganded transcription factors (TFs). Our knowledge of this circuitry is incomplete. Here we used DNA affinity purification followed by mass spectrometry to probe the network of hormone-regulated TFs by using phosphoenolpyruvate carboxykinase (Pck1) and glucose-6-phosphatase (G6pc) in liver and primary hepatocytes as model systems. The repertoire of insulin-regulated TFs is unexpectedly broad and diverse. Whereas in liver the two test promoters are regulated by largely overlapping sets of TFs, in primary hepatocytes Pck1 and G6pc regulation diverges. Insulin treatment preferentially results in increased occupancy by the two promoters, consistent with a model in which the hormone's primary role is to recruit corepressors rather than to clear activators. Nine insulin-responsive TFs are present in both models, but only FoxK1, FoxA2, ZFP91, and ZHX3 require an intact Pck1p insulin response sequence for binding. Knockdown of FoxK1 in primary hepatocytes decreased both glucose production and insulin's ability to suppress it. The findings expand the repertoire of insulin-dependent TFs and identify FoxK1 as a contributor to insulin signaling.


Assuntos
Fatores de Transcrição Forkhead/genética , Glucose-6-Fosfatase/genética , Hepatócitos/metabolismo , Insulina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Animais , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Gluconeogênese/genética , Camundongos , Cultura Primária de Células , Fatores de Transcrição
18.
Se Pu ; 37(3): 279-286, 2019 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-30900856

RESUMO

The application of boronic acid affinity chromatography to glycoprotein/glycopeptide enrichment is increasingly maturing. The enrichment selectivity, biocompatibility, and facile operation protocol are key aspects in efficient enrichment methods. In this work, a novel triazo-cyanide boronic acid functionalized material (TCNBA) was prepared using triazo-cyanide click chemistry. The TCNBA was proved to be successfully synthesized through infrared ray (IR) characterization. Subsequently, the glycopeptide/glycoprotein enrichment selectivity of the TCNBA was evaluated. Matrix-assisted laser desorption/ionization time-of-flight mass (MALDI-TOF MS) was employed for the glycopeptide enrichment selectivity evaluation. Taking the digestion of horseradish peroxidase (HRP) and immunoglobulin G (IgG) as samples, 13 and 11 glycopeptides could be characterized with improved signals after TCNBA enrichment, respectively. High abundance non-glycopeptides could be removed effectively from the eluting fraction. This result indicates the high glycopeptide enrichment selectivity of TCNBA. In addition, a mixture of HRP and bovine serum albumin (BSA) enzymatic solution (1:10, amount of substance ratio) was utilized as a sample, and five glycopeptide signals could be identified following enrichment. To evaluate the glycoprotein enrichment selectivity, sodium salt-polyacrylamide gel electrophoresis (SDS-PAGE) was adopted as an evaluation method. Mixtures of HRP, IgG, BSA, and ribonuclease B (RNaseB) proteins were employed as samples, and the results demonstrated that TCNBA had a high glycoprotein enrichment selectivity. The application of TCNBA to the analysis of a real biosample was also evaluated using human plasma. The results indicated the TCNBA could be utilized in large-scale glycoprotein analysis.


Assuntos
Ácidos Borônicos/química , Química Click , Cianetos/química , Glicopeptídeos/isolamento & purificação , Glicoproteínas/isolamento & purificação , Sílica Gel/química , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
19.
JCI Insight ; 4(3)2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30728336

RESUMO

Intronic polymorphisms in the α-ketoglutarate-dependent dioxygenase gene (FTO) that are highly associated with increased body weight have been implicated in the transcriptional control of a nearby ciliary gene, retinitis pigmentosa GTPase regulator-interacting protein-1 like (RPGRIP1L). Previous studies have shown that congenital Rpgrip1l hypomorphism in murine proopiomelanocortin (Pomc) neurons causes obesity by increasing food intake. Here, we show by congenital and adult-onset Rpgrip1l deletion in Pomc-expressing neurons that the hyperphagia and obesity are likely due to neurodevelopmental effects that are characterized by a reduction in the Pomc/Neuropeptide Y (Npy) neuronal number ratio and marked increases in arcuate hypothalamic-paraventricular hypothalamic (ARH-PVH) axonal projections. Biallelic RPGRIP1L mutations result in fewer cilia-positive human induced pluripotent stem cell-derived (iPSC-derived) neurons and blunted responses to Sonic Hedgehog (SHH). Isogenic human ARH-like embryonic stem cell-derived (ESc-derived) neurons homozygous for the obesity-risk alleles at rs8050136 or rs1421085 have decreased RPGRIP1L expression and have lower numbers of POMC neurons. RPGRIP1L overexpression increases POMC cell number. These findings suggest that apparently functional intronic polymorphisms affect hypothalamic RPGRIP1L expression and impact development of POMC neurons and their derivatives, leading to hyperphagia and increased adiposity.

20.
Water Sci Technol ; 76(9-10): 2802-2815, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29168720

RESUMO

There have been widespread concerns about solute transport problems in fractured media, e.g. the disposal of high-level radioactive waste in geological fractured rocks. Numerical simulation of particle tracking is gradually being employed to address these issues. Traditional predictions of radioactive waste transport using discrete fracture network (DFN) models often consider one particular realization of the fracture distribution based on fracture statistic features. This significantly underestimates the uncertainty of the risk of radioactive waste deposit evaluation. To adequately assess the uncertainty during the DFN modeling in a potential site for the disposal of high-level radioactive waste, this paper utilized the probabilistic distribution method (PDM). The method was applied to evaluate the risk of nuclear waste deposit in Beishan, China. Moreover, the impact of the number of realizations on the simulation results was analyzed. In particular, the differences between the modeling results of one realization and multiple realizations were demonstrated. Probabilistic distributions of 20 realizations at different times were also obtained. The results showed that the employed PDM can be used to describe the ranges of the contaminant particle transport. The high-possibility contaminated areas near the release point were more concentrated than the farther areas after 5E6 days, which was 25,400 m2.


Assuntos
Resíduos Radioativos/análise , China , Geologia , Modelos Estatísticos , Resíduos Radioativos/estatística & dados numéricos , Eliminação de Resíduos
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