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1.
Biomed Res Int ; 2022: 4239500, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692593

RESUMO

A large number of facts have shown that epigenetic modification and metabolic reprogramming represented by noncoding RNA play an important role in the invasion and metastasis of breast cancer, but the mechanism is not clear. The purpose of our study is to find a new biomarker of breast cancer and to provide a new perspective for regulating glucose metabolism and aerobic glycolysis of BC. In this paper, by downregulating C-myc protein, our team found that the expression of long-chain noncoding RNATSPAR-AS2 was significantly downregulated. However, the expression of long-chain noncoding RNASPAR-AS2 in BC is relatively high, and the prognosis is poor. TSPEAR-AS2 can promote the malignant phenotype of BC cells, including proliferation, apoptosis, invasion and metastasis, and glycolysis. At the same time, TSPEAR-AS2 can also upregulate the expression of GLUT1, an important regulator of glycolysis, thus promoting the metabolic reprogramming of BC. Molecular mechanism experiments show that TSPEAR-AS2 may promote the expression of GLUT1 by participating in IGF2BP2 modified by the GLUT1 gene. Our results suggest that the C-myc/TSPEAR-AS2/GLUT1 axis promotes the invasion and metastasis of BC by inducing glucose metabolism reprogramming. However, more phenotypic and molecular mechanism results need to be further verified.


Assuntos
Neoplasias da Mama , MicroRNAs , RNA Longo não Codificante , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Glicólise/genética , Humanos , MicroRNAs/genética , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/genética , Proteínas de Ligação a RNA/genética
2.
Sci Rep ; 12(1): 10645, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739198

RESUMO

We present a mathematical model of key glucose metabolic pathways in two cells of the human retina: the rods and the retinal pigmented epithelium (RPE). Computational simulations of glucose transporter 1 (GLUT1) inhibition in the model accurately reproduce experimental data from conditional knockout mice and reveal that modification of GLUT1 expression levels of both cells differentially impacts their metabolism. We hypothesize that, under glucose scarcity, the RPE's energy producing pathways are altered in order to preserve its functionality, impacting the photoreceptors' outer segment renewal. On the other hand, when glucose is limited in the rods, aerobic glycolysis is preserved, which maintains the lactate contribution to the RPE.


Assuntos
Transportador de Glucose Tipo 1 , Epitélio Pigmentado da Retina , Células Fotorreceptoras Retinianas Bastonetes , Animais , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Camundongos , Modelos Teóricos , Epitélio Pigmentado da Retina/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo
3.
Cells ; 11(11)2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35681497

RESUMO

In this study, we investigated the relationship between the tumor immune microenvironment (TIME), histological differentiation and hypoxia in patients with muscular-invasive urothelial carcinomas (MIUC) after radical cystectomy. Forty-two cases of pT2-3N0M0 MIUCs underwent clinical, histological and immunohistochemical evaluation by counting CD8+, FOXP3+, CD68+, CD163+ cells and polymorphonuclear leukocytes (PMN) in intra-tumoral and peritumoral areas, assessing PD-L1 and GLUT1 expression for defining the impact of tumor immune contexture on patients' outcomes. Five-year survival rates and overall survival were calculated. Most of the MIUCs demonstrated the immune-desert or immune-excluded TIME, reflecting altered mechanisms of T-cells' activation or traffic into tumors. Tumor immune contexture was closely related to histological differentiation. CD8+ cells were scant in MIUCs with papillary and squamous differentiation, while basal-like or mesenchymal-like histological differentiation was associated with increased density of CD8+ cells. A high rate of PD-L1 expression (47.6%) was not related to immune cell infiltration. M2-macrophages predominated under CD8+ lymphocytes. The abundance of PMN and CD163+ macrophages in MIUCs was associated with high GLUT1 expression. CD8+, CD68+, FOXP3+ cells and PD-L1 status did not affect patients' outcomes, while high CD163+ density and PMN infiltration were associated with the unfavorable outcome of patients with MIUC. These data drive the hypothesis that in MIUC, immune escape mechanisms are shifted towards the role of the innate immunity cells rather than CD8+ lymphocytes' functioning.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/metabolismo , Carcinoma de Células de Transição/patologia , Fatores de Transcrição Forkhead/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Linfócitos do Interstício Tumoral , Microambiente Tumoral , Neoplasias da Bexiga Urinária/patologia
4.
FASEB J ; 36(8): e22428, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35766190

RESUMO

Photoreceptors consume glucose supplied by the choriocapillaris to support phototransduction and outer segment (OS) renewal. Reduced glucose supply underlies photoreceptor cell death in inherited retinal degeneration and age-related retinal disease. We have previously shown that restricting glucose transport into the outer retina by conditional deletion of Slc2a1 encoding GLUT1 resulted in photoreceptor loss and impaired OS renewal. However, retinal neurons, glia, and the retinal pigment epithelium play specialized, synergistic roles in metabolite supply and exchange, and the cell-specific map of glucose uptake and utilization in the retina is incomplete. In these studies, we conditionally deleted Slc2a1 in a pan-retinal or rod-specific manner to better understand how glucose is utilized in the retina. Using non-invasive ocular imaging, electroretinography, and histochemical and biochemical analyses we show that genetic deletion of Slc2a1 from retinal neurons and Müller glia results in reduced OS growth and progressive rod but not cone photoreceptor cell death. Rhodopsin levels were severely decreased even at postnatal day 20 when OS length was relatively normal. Arrestin levels were not changed suggesting that glucose uptake is required to synthesize membrane glycoproteins. Rod-specific deletion of Slc2a1 resulted in similar changes in OS length and rod photoreceptor cell death. These studies demonstrate that glucose is an essential carbon source for rod photoreceptor cell OS maintenance and viability.


Assuntos
Células Fotorreceptoras Retinianas Cones , Degeneração Retiniana , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Células Fotorreceptoras Retinianas Cones/metabolismo , Degeneração Retiniana/metabolismo , Segmento Externo da Célula Bastonete/metabolismo
5.
Biochim Biophys Acta Biomembr ; 1864(9): 183975, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35654150

RESUMO

Glucose transporter GLUT1 is ubiquitously expressed in the human body from the red cells to the blood-brain barrier to the skeletal muscles. It is physiologically relevant to understand how GLUT1 facilitates diffusion of glucose across the cell membrane. It is also pathologically relevant because GLUT1 deficiency causes neurological disorders and anemia and because GLUT1 overexpression fuels the abnormal growth of cancer cells. This article presents a quantitative investigation of GLUT1 based on all-atom molecular-dynamics (MD) simulations of the transporter embedded in lipid bilayers of asymmetric inner-and-outer-leaflet lipid compositions, subject to asymmetric intra-and-extra-cellular environments. This is in contrast with the current literature of MD studies that have not considered both of the aforementioned asymmetries of the cell membrane. The equilibrium (unbiased) dynamics of GLUT1 shows that it can facilitate glucose diffusion across the cell membrane without undergoing large-scale conformational motions. The Gibbs free-energy profile, which is still lacking in the current literature of GLUT1, quantitatively characterizes the diffusion path of glucose from the periplasm, through an extracellular gate of GLUT1, on to the binding site, and off to the cytoplasm. This transport mechanism is validated by the experimental data that GLUT1 has low water-permeability, uptake-efflux symmetry, and 10 kcal/mol Arrhenius activation barrier around 37 °C.


Assuntos
Glucose , Proteínas de Transporte de Monossacarídeos , Transporte Biológico , Difusão , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Proteínas de Transporte de Monossacarídeos/metabolismo
6.
Eur J Paediatr Neurol ; 38: 73-76, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35500464

RESUMO

In the literature, microcephaly is considered as part of the classical phenotype of glucose transporter 1 deficiency syndrome (GLUT1DS), and previous cohort studies reported a prevalence of microcephaly of around 50%. In our clinical experience, however, only very few patients with GLUT1DS appear to have microcephaly. Therefore, we conducted an observational study among a large cohort of Dutch patients with GLUT1DS to investigate the prevalence of microcephaly, defined as < 2 standard deviations (SD) below the mean. We analysed the head circumference of 54 patients and found a prevalence of microcephaly at last known measurement of 6.5%. Notably, none of the patients had a head circumference < -3 SD. However, we learned that 75.9% of the patients had a head circumference below 0 SD. This study shows that microcephaly occurs less often than previously thought in patients with GLUT1DS, and that primary or secondary microcephaly does not seem to be a sign for clinicians to suspect GLUT1DS. As a group, however, patients with GLUT1DS seem to have decreased head circumference compared to healthy individuals and as such, our study suggests that early brain development and brain growth may be compromised in GLUT1DS.


Assuntos
Erros Inatos do Metabolismo dos Carboidratos , Dieta Cetogênica , Transportador de Glucose Tipo 1/metabolismo , Microcefalia , Transportador de Glucose Tipo 1/genética , Humanos , Microcefalia/complicações , Microcefalia/epidemiologia , Proteínas de Transporte de Monossacarídeos/deficiência
7.
Cell Biochem Funct ; 40(4): 417-425, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35575602

RESUMO

It has been well known that oxidative stress and increased intracellular reactive oxygen species (ROS) have a pivotal role in disrupting the insulin signaling pathways leading to cellular insulin resistance. In this study, we evaluated arbutin's effects on glucose uptake by GLUT4 and cytoprotective properties in the L6 skeletal muscle cell line. The effect of arbutin and tertiary butyl hydrogen peroxide (t-BHP) on glucose uptake in cultured L6 cells was investigated by flow cytometry. We also evaluated gene expression levels of GLUT1 and GLUT4 in the L6 cells by quantitative real-time polymerase chain reaction analysis. The results from the study demonstrated that the optimum ROS generation occurred 3 h after 100 µM t-BHP treatment and pretreatment with arbutin (500 and 1000 µM) significantly inhibited the t-BHP induced ROS generation (p < .05). Our result indicated that 3 h pretreatment of L6 cells with 1000 µM of arbutin before 50 µM t-BHP significantly increased glucose uptake than the 50 µM t-BHP alone group (p < .05). Our findings may suggest that an increase in the uptake of 2-NBDG by L6 cells with arbutin pretreatment can be associated with increased expression of GLUT4 and GLUT1 under oxidative stress.


Assuntos
Arbutina , Glucose , Arbutina/metabolismo , Arbutina/farmacologia , Linhagem Celular , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Insulina/farmacologia , Músculo Esquelético/metabolismo , Espécies Reativas de Oxigênio/metabolismo
8.
FASEB J ; 36(6): e22377, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35608871

RESUMO

Osteoarthritis (OA) is the leading joint disease characterized by cartilage destruction and loss of mobility. Accumulating evidence indicates that the incidence and severity of OA increases with diabetes, implicating systemic glucose metabolism in joint health. However, a definitive link between cellular metabolism in articular cartilage and OA pathogenesis is not yet established. Here, we report that in mice surgically induced to develop knee OA through destabilization of medial meniscus (DMM), expression of the main glucose transporter Glut1 is notably reduced in joint cartilage. Inducible deletion of Glut1 specifically in the Prg4-expressing articular cartilage accelerates cartilage loss in DMM-induced OA. Conversely, forced expression of Glut1 protects against cartilage destruction following DMM. Moreover, in mice with type I diabetes, both Glut1 expression and the rate of glycolysis are diminished in the articular cartilage, and the diabetic mice exhibit more severe cartilage destruction than their nondiabetic counterparts following DMM. The results provide proof of concept that boosting glucose metabolism in articular chondrocytes may ameliorate cartilage degeneration in OA.


Assuntos
Cartilagem Articular , Diabetes Mellitus Experimental , Osteoartrite , Animais , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Camundongos , Osteoartrite/metabolismo
9.
Int J Biol Sci ; 18(8): 3374-3389, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35637944

RESUMO

Intestinal inflammation is a vital precipitating factor of colorectal cancer (CRC), but the underlying mechanisms are still elusive. TANK-binding kinase 1 (TBK1) is a core enzyme downstream of several inflammatory signals. Recent studies brought the impacts of TBK1 in malignant disease to the forefront, we found aberrant TBK1 expression in CRC is correlated with CRC progression. TBK1 inhibition impaired CRC cell proliferation, migration, drug resistance and tumor growth. Bioinformatic analysis and experiments in vitro showed overexpressed TBK1 inhibited mTORC1 signaling activation in CRC along with elevated GLUT1 expression without inducing GLUT1 translation. TBK1 mediated mTORC1 inhibition induces intracellular autophagy, which in turn decreasing GLUT1 degradation. As a rescue, blocking of autophagosome and retromer respectively via autophagy-related gene 7 (ATG7) or TBC1 Domain Family Member 5 (TBC1D5) silence diminished the regulation of TBK1 to GLUT1. GLUT1 staining presented that TBK1 facilitated GLUT1 membrane translocation which subsequently enhanced glucose consumption. Inhibitor of TBK1 also decreased GLUT1 expression which potentiated drug-sensitivity of CRC cell. Collectively, TBK1 facilitates glucose consumption for supporting CRC progression via initiating mTORC1 inhibition induced autophagy which decreases GLUT1 degradation and increases GLUT1 membrane location. The adaptive signaling cascade between TBK1 and GLUT1 proposes a new strategy for CRC therapy.


Assuntos
Neoplasias Colorretais , Transportador de Glucose Tipo 1 , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina , Neoplasias Colorretais/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transdução de Sinais
10.
J Histochem Cytochem ; 70(6): 437-446, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35615882

RESUMO

Metabolic reprogramming is typical in cancerous cells and is required for proliferation and cellular survival. In addition, oncoproteins of high-risk human papillomavirus (HR-HPV) are involved in this process. This study evaluated the relationship between glucose transporter I (GLUT1), lactate dehydrogenase A (LDHA), and monocarboxylate transporter type 4 (MCT4) expression and cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma (ICC) with HR-HPV infection. The protein expression was evaluated in women with CIN I (n=20), CIN II/III (n=16), or ICC (n=24) by immunohistochemistry. The protein expression was analyzed qualitatively by van Zummeren score and quantitatively by Image ProPlus 6 software. LDHA expression increases in HPV-16 infection. In the CIN I group, GLUT1 immunostaining has a 35% protein expression at the membrane level at more than two thirds of the epithelium, which increased by 21.25% more in CIN II/III in more than two thirds of the epithelium. While LDHA and MCT4 in CIN I mostly do not present immunostaining, or this was only limited to the basal stratum, this expression is increased in CIN II/III and ICC cases. The GLUT1, LDHA, and MCT4 expression increased in ICC. The overexpression in high-grade CIN with HR-HPV infection shows a higher risk for cervical carcinoma progression.


Assuntos
Neoplasia Intraepitelial Cervical , Transportador de Glucose Tipo 1/metabolismo , L-Lactato Desidrogenase/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Neoplasia Intraepitelial Cervical/metabolismo , Neoplasia Intraepitelial Cervical/patologia , Feminino , Proteínas Facilitadoras de Transporte de Glucose , Humanos , Lactato Desidrogenase 5 , Infecções por Papillomavirus/patologia , Neoplasias do Colo do Útero/metabolismo
11.
J Adv Res ; 37: 119-131, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35499042

RESUMO

Introduction: O-linked ß-D-N-acetylglucosamine (O-GlcNAc) modification is a post-translational modification in which a single O-GlcNAc is added to serine or threonine residues in nuclear, cytoplasmic, and mitochondrial proteins, and is involved in a variety of physiological processes. Objectives: In the present study, the role of O-GlcNAcylation in embryo implantation was evaluated. Furthermore, whether O-GlcNAcylation is involved in orchestrating glucose metabolism to influence endometrial cell physiological functions was investigated. Methods: Different endometrial tissues were detected using immunohistochemistry. Pregnant mouse models were established to verify molecular expression. O-GlcNAc transferase and aquaporin 3 (AQP3) knockdown were used to detect embryo implantation efficiency in vitro and in vivo. Western blotting and immunofluorescence were used to detect protein expression and stability. Dual luciferase reporter assay and chromatin immunoprecipitation (ChIP) were used to verify the binding transcription factor. Glycolysis was detected using bioenergy analyzer, and metabolites were analyzed using isotope 13C-labeled LC-MS. Metabolic-related genes were determined using RNA sequencing. Results: Activation of endometrial hexosamine biosynthetic pathway (HBP) caused elevated O-GlcNAcylation during the window of implantation, affecting endometrial cell function and embryo implantation. Specifically, elevated O-GlcNAcylation increased glucose uptake via glucose transporter 1 (GLUT1) leading to glucose metabolic flow into the pentose phosphate pathways and HBP, which regulate the metabolic reprogramming of endometrial cells. Furthermore, O-GlcNAcylation mediated the intracellular transport of glycerol to support and compensate for glycolysis through regulation of AQP3. Unexpectedly, elevated AQP3 also increased glucose uptake via GLUT1. These processes maintained higher metabolic requirements for endometrial physiology. Furthermore, the transcription factor SP1 specifically bound to the AQP3 promoter region, and O-GlcNAcylation of SP1 increased its stability and transcriptional regulation of AQP3 which is associated with O-GlcNAcylation of SP1. Conclusion: Overall, O-GlcNAcylation regulated glucose metabolism in endometrial cells, and AQP3-mediated compensation provides new insights into the communication between glycolysis and O-GlcNAcylation.


Assuntos
Aquaporina 3 , Glicólise , Animais , Aquaporina 3/metabolismo , Implantação do Embrião , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Hexosaminas , Camundongos
12.
Arch Biochem Biophys ; 723: 109255, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35452623

RESUMO

Age-related cataract (ARC) is a severe visual impairment disease and its pathogenesis remains unclear. This study investigated the relevance of MST2/YAP1/GLUT1 in ARC development in vivo and in vitro, and explored the role and possible mechanisms of this pathway in oxidative damage-mediated apoptosis of lens epithelial cells (LECs). Western blot analysis and immunohistochemistry showed that MST2 and phosphorylated (p)-YAP (Ser127) protein levels were increased, and YAP1 and GLUT1 protein levels were decreased in LECs of ARC patients and aged mice. Additionally, differential expression of MST2 and YAP1 was associated with H2O2-induced apoptosis of human lens epithelial B3 (HLE-B3) cells. CCK-8 and Hoechst 33,342 apoptosis assays showed that MST2 and YAP1 were involved in H2O2-induced apoptosis of LECs. Subsequent experiments showed that, during MST2-mediated H2O2-induced apoptosis, p-YAP (Ser127) levels were elevated and immunofluorescence revealed nucleoplasmic translocation and inhibition of YAP1 protein expression. Furthermore, GLUT1 was in turn synergistically transcriptionally regulated by YAP1-TEAD1 in dual luciferase reporter assays. In conclusion, our study indicates that the MST2/YAP1/GLUT1 pathway plays a major role in the pathogenesis of ARC and LECs apoptosis, providing a new direction for future development of targeted inhibitors that block this signaling pathway to prevent, delay, or even cure ARC.


Assuntos
Catarata , Cristalino , /metabolismo , Animais , Apoptose , Catarata/metabolismo , Células Epiteliais/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Camundongos , Estresse Oxidativo
13.
Mol Cell Biochem ; 477(7): 1959-1971, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35380292

RESUMO

OBJECTIVE: Peritoneal fibrosis (PF) is commonly induced by bioincompatible dialysate exposure during peritoneal dialysis, but the underlying mechanisms remain elusive. This study aimed to investigate the roles of peroxisome proliferator-activated receptor gamma (PPARγ) in PF pathogenesis. METHODS: Rat and cellular PF models were established by high glucose dialysate and lipopolysaccharide treatments. Serum creatinine, urea nitrogen, and glucose contents were detected by ELISA. Histological evaluation was done through H&E and Masson staining. GLUT1, PPARγ, and other protein expression were measured by qRT-PCR, western blotting, and IHC. PPARγ and GLUT1 subcellular distribution were detected using confocal microscopy. Cell proliferation was assessed by MTT and Edu staining. RESULTS: Serum creatinine, urea nitrogen and glucose, and PPARγ and GLUT1 expression in rat PF model were reduced by PPARγ agonists Rosiglitazone or 15d-PGJ2 and elevated by antagonist GW9662. Rosiglitazone or 15d-PGJ2 repressed and GW9662 aggravated peritoneal fibrosis in rat PF model. PPARγ and GLUT1 were mainly localized in nucleus and cytosols of peritoneal mesothelial cells, respectively, which were reduced in cellular PF model, enhanced by Rosiglitazone or 15d-PGJ2, and repressed by GW9662. TGF-ß and a-SMA expression was elevated in cellular PF model, which was inhibited by Rosiglitazone or 15d-PGJ2 and promoted by GW9662. PPARγ silencing reduced GLUT1, elevated a-SMA and TGF-b expression, and promoted peritoneal mesothelial cell proliferation, which were oppositely changed by PPARγ overexpression. CONCLUSION: PPARγ inhibited high glucose-induced peritoneal fibrosis progression through elevating GLUT1 expression and repressing peritoneal mesothelial cell proliferation.


Assuntos
Transportador de Glucose Tipo 1 , PPAR gama , Fibrose Peritoneal , Tiazolidinedionas , Animais , Proliferação de Células , Creatinina , Soluções para Diálise/farmacologia , Glucose/farmacologia , Transportador de Glucose Tipo 1/metabolismo , Nitrogênio/metabolismo , Nitrogênio/farmacologia , PPAR gama/agonistas , PPAR gama/genética , Fibrose Peritoneal/induzido quimicamente , Fibrose Peritoneal/genética , Prostaglandina D2 , Ratos , Rosiglitazona/farmacologia , Tiazolidinedionas/farmacologia , Fator de Crescimento Transformador beta/metabolismo , Ureia
14.
Theriogenology ; 185: 78-87, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35390592

RESUMO

The oviduct of Chinese brown frog (Rana dybowskii) displays seasonal morphological and functional changes, which expands specifically during pre-brumation. To uncover the molecular mechanism underlying this phenomenon, we firstly confirmed the increased weight and enlarged diameter of the oviduct in pre-brumation by morphological observation. Interestingly, the glycogen content in the oviduct increased significantly during pre-brumation, indicating Rana dybowskii stores energy in the oviduct before brumation. Transcriptome analysis further identified the differentially expressed genes in the synthesis and metabolism pathways of carbohydrates in the oviduct during pre-brumation. Based on that evidence, we focused on the mRNA and protein expression of glycogenic genes in the oviduct of Rana dybowskii. qPCR confirmed that the expression of glycolysis and glycogenesis-related genes were up-regulated while gluconeogenesis-related genes were down-regulated during pre-brumation. Western blot data showed that glucose transporter GLUT1 and glycogen synthesis-regulation proteins including GYS, and p-GSK-3ß were highly expressed in the oviduct during pre-brumation. Moreover, immunohistochemical data showed that GLUT1, GYS, p-GYS, GSK-3ß and p-GSK-3ß were expressed regionally in the oviduct of Rana dybowskii. The data suggests that glycogen synthesis may be involved in the oviductal expansion of Rana dybowskii during the pre-brumation.


Assuntos
Glicogênio , Ranidae , Animais , China , Feminino , Transportador de Glucose Tipo 1/metabolismo , Glicogênio/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Oviductos/metabolismo , Ranidae/anatomia & histologia , Ranidae/genética , Ranidae/metabolismo
15.
Biochem Biophys Res Commun ; 607: 20-27, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35366539

RESUMO

Plasma glucose levels are homeostatically regulated within strict boundaries and are maintained through a balance between peripheral glucose uptake and hepatic glucose production. However, little is known about the regulatory mechanism of glucose uptake in adipocytes during fasting. Under fasting conditions, the expression levels of 8 glycolytic enzymes were significantly reduced in adipose tissue. Among them, we focused on lactate dehydrogenase A (LDHA), the last enzyme of the glycolytic pathway. Under fasting conditions, both LDHA and Glut1 protein levels tended to decrease in adipose tissue. To elucidate the significance of LDHA in adipocytes, we generated adipocyte-specific LDHA knockout mice (AdLDHAKO) for the first time. AdLDHAKO mice showed no apparent changes in body weight or tissue weight. Under fasting conditions, AdLDHAKO mice exhibited a significant reduction in Glut1 protein levels and glucose uptake in adipose tissues compared with control mice. Similarly, siRNA of LDHA in 3T3-L1 adipocytes reduced Glut1 protein levels and basal glucose uptake. Moreover, treatment with bafilomycin A1, an inhibitor of lysosomal protein degradation, restored Glut1 protein levels by siRNA of LDHA. These results indicate that LDHA regulates Glut1 expression and basal glucose uptake in adipocytes.


Assuntos
Adipócitos , L-Lactato Desidrogenase , Adipócitos/metabolismo , Animais , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Insulina/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lactato Desidrogenase 5 , Camundongos , RNA Interferente Pequeno/metabolismo
16.
J Cell Mol Med ; 26(10): 2881-2894, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35415942

RESUMO

Hypoxic resistance is the main obstacle to radiotherapy for laryngeal carcinoma. Our previous study indicated that hypoxia-inducible factor 1α (HIF-1α) and glucose transporter 1 (Glut-1) double knockout reduced tumour biological behaviour in laryngeal carcinoma cells. However, their radioresistance mechanism remains unclear. In this study, cell viability was determined by CCK8 assay. Glucose uptake capability was evaluated by measurement of 18 F-fluorodeoxyglucose radioactivity. A tumour xenograft model was established by subcutaneous injection of Tu212 cells. Tumour histopathology was determined by haematoxylin and eosin staining, immunohistochemical staining, and TUNEL assays. Signalling transduction was evaluated by Western blotting. We found that hypoxia induced radioresistance in Tu212 cells accompanied by increased glucose uptake capability and activation of the PI3K/Akt/mTOR pathway. Inhibition of PI3K/Akt/mTOR activity abolished hypoxia-induced radioresistance and glucose absorption. Mechanistic analysis revealed that hypoxia promoted higher expressions of HIF-1α and Glut-1. Moreover, the PI3K/Akt/mTOR pathway was a positive mediator of HIF-1α and/or Glut-1 in the presence of irradiation. HIF-1α and/or Glut-1 knockout significantly reduced cell viability, glucose uptake and PI3K/Akt/mTOR activity, all of which were induced by hypoxia in the presence of irradiation. In vivo analysis showed that knockout of HIF-1α and/or Glut-1 also inhibited tumour growth by promoting cell apoptosis, more robustly compared with the PI3K inhibitor wortmannin, particularly in tumours with knockout of both HIF-1α and Glut-1. HIF-1α and/or Glut-1 knockout also abrogated PI3K/Akt/mTOR signalling transduction in tumour tissues, in a manner similar to wortmannin. HIF-1α and/or Glut-1 knockout facilitated radiosensitivity in laryngeal carcinoma Tu212 cells by regulation of the PI3K/Akt/mTOR pathway.


Assuntos
Carcinoma , Transportador de Glucose Tipo 1 , Subunidade alfa do Fator 1 Induzível por Hipóxia , Neoplasias Laríngeas , Animais , Sistemas CRISPR-Cas , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/radioterapia , Linhagem Celular Tumoral , Glucose , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/radioterapia , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tolerância a Radiação/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Wortmanina
17.
Cell Host Microbe ; 30(4): 530-544.e6, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35316647

RESUMO

Combating fungal pathogens poses metabolic challenges for neutrophils, key innate cells in anti-Candida albicans immunity, yet how host-pathogen interactions cause remodeling of the neutrophil metabolism is unclear. We show that neutrophils mediate renal immunity to disseminated candidiasis by upregulating glucose uptake via selective expression of glucose transporter 1 (Glut1). Mechanistically, dectin-1-mediated recognition of ß-glucan leads to activation of PKCδ, which triggers phosphorylation, localization, and early glucose transport by a pool of pre-formed Glut1 in neutrophils. These events are followed by increased Glut1 gene transcription, leading to more sustained Glut1 accumulation, which is also dependent on the ß-glucan/dectin-1/CARD9 axis. Card9-deficient neutrophils show diminished glucose incorporation in candidiasis. Neutrophil-specific Glut1-ablated mice exhibit increased mortality in candidiasis caused by compromised neutrophil phagocytosis, reactive oxygen species (ROS), and neutrophil extracellular trap (NET) formation. In human neutrophils, ß-glucan triggers metabolic remodeling and enhances candidacidal function. Our data show that the host-pathogen interface increases glycolytic activity in neutrophils by regulating Glut1 expression, localization, and function.


Assuntos
Candidíase , Transportador de Glucose Tipo 1 , Neutrófilos , beta-Glucanas , Animais , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Candida albicans , Candidíase/imunologia , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Camundongos , Neutrófilos/imunologia , beta-Glucanas/metabolismo
18.
Reprod Biomed Online ; 44(4): 595-607, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35232674

RESUMO

RESEARCH QUESTION: How does progesterone improve fetal outcome and change the expression of placental glucose transporters (GLUT) in dexamethasone-induced intrauterine growth restriction (IUGR)? DESIGN: A total of 64 rats were divided randomly into four different treatment groups based on daily i.p. injections of either saline or dexamethasone in the presence or absence of progesterone. Injections started on the 15th day of gestation (15dg) and lasted until the day of sacrifice at 19dg or 21dg. Maternal plasma progesterone concentrations were measured by enzyme-linked immunosorbent assay. The gene and protein expression of placental GLUT1 and GLUT3 were evaluated in the placental labyrinth and basal zones by real-time polymerase chain reaction and Western blotting, respectively. The localization of GLUT1 and GLUT3 was evaluated by immunohistochemistry. RESULTS: Dexamethasone induced significant decreases in maternal serum progesterone concentrations (P = 0.029) and placental (P < 0.001) and fetal body (P = 0.009) weights. Dexamethasone also reduced the expression of GLUT1 in the labyrinth zone (P = 0.028) and GLUT3 in both the labyrinth (P = 0.002) and basal zones (P = 0.026). Coadministration of dexamethasone and progesterone prevented the reduction in fetal body weight, placental weight and placental GLUT expression compared with that seen in dexamethasone-treated groups. CONCLUSION: These results suggest that progesterone prevents the significant reduction in fetal and placental weights in dexamethasone-induced IUGR, possibly through improving the expression of placental GLUT.


Assuntos
Retardo do Crescimento Fetal , Placenta , Animais , Dexametasona/efeitos adversos , Dexametasona/metabolismo , Feminino , Retardo do Crescimento Fetal/induzido quimicamente , Glucose/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/genética , Transportador de Glucose Tipo 3/metabolismo , Humanos , Placenta/metabolismo , Gravidez , Progesterona/metabolismo , Ratos
19.
Placenta ; 121: 155-163, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35349915

RESUMO

INTRODUCTION: Cell-cell fusion of cytotrophoblasts into the syncytiotrophoblast layer is a key process in placental development. Syncytin, an endogenous retroviral envelope protein, is expressed in placental trophoblasts and specifically mediates syncytiotrophoblast layer formation. Syncytin deficiency has been observed in fetal growth-restricted placentas. Abnormal fetal growth, especially fetal growth restriction, is associated with the decreased expression of glucose transporters. Here, we aimed to determine the role of syncytin in fetal growth restriction in placental glucose transport capacity. METHODS: To better explore the function of syncytin in fetal growth-restricted placenta, we generated an inducible knockout mouse model of syncytin-a gene. The expression levels of glucose transporters in BeWo cells were measured before and after HERV-W knockdown. RESULTS: Syncytin-A disruption was associated with significant abnormalities in placental and fetal development in mice. Syncytin-A destruction causes extensive abnormalities in the maternal-fetal exchange structures in the labyrinth, including an extremely reduced number and dramatically irregular distribution of fetal vessels. Moreover, glucose transporter 1, glucose transporters 3, and connexin 26 expression levels decreased after E14.5. Consistently, low glucose transporter 1, glucose transporter 3, and connexin 26 levels were observed in HERV-W-silenced BeWo cells. DISCUSSION: Syncytin-A is crucial for both syncytiotrophoblast layer development and morphogenesis, suggesting that syncytin-A disruption leads to fetal growth restriction associated with abnormalities in the maternal-fetal exchange barrier and decreased glucose transport.


Assuntos
Retardo do Crescimento Fetal , Placenta , Animais , Conexina 26/metabolismo , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Produtos do Gene env/genética , Produtos do Gene env/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Camundongos , Camundongos Knockout , Placenta/metabolismo , Gravidez , Proteínas da Gravidez , Trofoblastos/metabolismo
20.
EMBO J ; 41(9): e109890, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35243676

RESUMO

Endothelial cells differ from other cell types responsible for the formation of the vascular wall in their unusual reliance on glycolysis for most energy needs, which results in extensive production of lactate. We find that endothelium-derived lactate is taken up by pericytes, and contributes substantially to pericyte metabolism including energy generation and amino acid biosynthesis. Endothelial-pericyte proximity is required to facilitate the transport of endothelium-derived lactate into pericytes. Inhibition of lactate production in the endothelium by deletion of the glucose transporter-1 (GLUT1) in mice results in loss of pericyte coverage in the retina and brain vasculatures, leading to the blood-brain barrier breakdown and increased permeability. These abnormalities can be largely restored by oral lactate administration. Our studies demonstrate an unexpected link between endothelial and pericyte metabolisms and the role of endothelial lactate production in the maintenance of the blood-brain barrier integrity. In addition, our observations indicate that lactate supplementation could be a useful therapeutic approach for GLUT1 deficiency metabolic syndrome patients.


Assuntos
Barreira Hematoencefálica , Pericitos , Animais , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Endotélio/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Ácido Láctico/metabolismo , Camundongos , Pericitos/metabolismo
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