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1.
Annu Rev Cell Dev Biol ; 37: 341-367, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34351784

RESUMO

Nutrients are vital to life through intertwined sensing, signaling, and metabolic processes. Emerging research focuses on how distinct nutrient signaling networks integrate and coordinate gene expression, metabolism, growth, and survival. We review the multifaceted roles of sugars, nitrate, and phosphate as essential plant nutrients in controlling complex molecular and cellular mechanisms of dynamic signaling networks. Key advances in central sugar and energy signaling mechanisms mediated by the evolutionarily conserved master regulators HEXOKINASE1 (HXK1), TARGET OF RAPAMYCIN (TOR), and SNF1-RELATED PROTEIN KINASE1 (SNRK1) are discussed. Significant progress in primary nitrate sensing, calcium signaling, transcriptome analysis, and root-shoot communication to shape plant biomass and architecture are elaborated. Discoveries on intracellular and extracellular phosphate signaling and the intimate connections with nitrate and sugar signaling are examined. This review highlights the dynamic nutrient, energy, growth, and stress signaling networks that orchestrate systemwide transcriptional, translational, and metabolic reprogramming, modulate growth and developmental programs, and respond to environmental cues.


Assuntos
Desenvolvimento Vegetal , Transdução de Sinais , Nutrientes , Desenvolvimento Vegetal/genética , Plantas/genética , Plantas/metabolismo , Transdução de Sinais/genética
2.
Cell ; 177(5): 1201-1216.e19, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31031005

RESUMO

Innate immune responses are intricately linked with intracellular metabolism of myeloid cells. Toll-like receptor (TLR) stimulation shifts intracellular metabolism toward glycolysis, while anti-inflammatory signals depend on enhanced mitochondrial respiration. How exogenous metabolic signals affect the immune response is unknown. We demonstrate that TLR-dependent responses of dendritic cells (DCs) are exacerbated by a high-fatty-acid (FA) metabolic environment. FAs suppress the TLR-induced hexokinase activity and perturb tricarboxylic acid cycle metabolism. These metabolic changes enhance mitochondrial reactive oxygen species (mtROS) production and, in turn, the unfolded protein response (UPR), leading to a distinct transcriptomic signature with IL-23 as hallmark. Interestingly, chemical or genetic suppression of glycolysis was sufficient to induce this specific immune response. Conversely, reducing mtROS production or DC-specific deficiency in XBP1 attenuated IL-23 expression and skin inflammation in an IL-23-dependent model of psoriasis. Thus, fine-tuning of innate immunity depends on optimization of metabolic demands and minimization of mtROS-induced UPR.


Assuntos
Microambiente Celular/imunologia , Células Dendríticas/imunologia , Imunidade Inata , Mitocôndrias/imunologia , Espécies Reativas de Oxigênio/imunologia , Resposta a Proteínas não Dobradas/imunologia , Animais , Microambiente Celular/genética , Ciclo do Ácido Cítrico/genética , Ciclo do Ácido Cítrico/imunologia , Células Dendríticas/patologia , Hexoquinase/genética , Hexoquinase/imunologia , Inflamação/genética , Inflamação/imunologia , Inflamação/patologia , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia , Resposta a Proteínas não Dobradas/genética , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/imunologia
3.
Mol Cell ; 84(14): 2732-2746.e5, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38981483

RESUMO

Metabolic enzymes can adapt during energy stress, but the consequences of these adaptations remain understudied. Here, we discovered that hexokinase 1 (HK1), a key glycolytic enzyme, forms rings around mitochondria during energy stress. These HK1-rings constrict mitochondria at contact sites with the endoplasmic reticulum (ER) and mitochondrial dynamics protein (MiD51). HK1-rings prevent mitochondrial fission by displacing the dynamin-related protein 1 (Drp1) from mitochondrial fission factor (Mff) and mitochondrial fission 1 protein (Fis1). The disassembly of HK1-rings during energy restoration correlated with mitochondrial fission. Mechanistically, we identified that the lack of ATP and glucose-6-phosphate (G6P) promotes the formation of HK1-rings. Mutations that affect the formation of HK1-rings showed that HK1-rings rewire cellular metabolism toward increased TCA cycle activity. Our findings highlight that HK1 is an energy stress sensor that regulates the shape, connectivity, and metabolic activity of mitochondria. Thus, the formation of HK1-rings may affect mitochondrial function in energy-stress-related pathologies.


Assuntos
Dinaminas , Metabolismo Energético , Hexoquinase , Mitocôndrias , Dinâmica Mitocondrial , Proteínas Mitocondriais , Hexoquinase/metabolismo , Hexoquinase/genética , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/genética , Mitocôndrias/enzimologia , Dinaminas/metabolismo , Dinaminas/genética , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Animais , Trifosfato de Adenosina/metabolismo , Estresse Fisiológico , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Ciclo do Ácido Cítrico , Glucose-6-Fosfato/metabolismo , Camundongos , Células HeLa , Células HEK293 , GTP Fosfo-Hidrolases/metabolismo , GTP Fosfo-Hidrolases/genética , Mutação
4.
Mol Cell ; 82(7): 1261-1277.e9, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35305311

RESUMO

The product of hexokinase (HK) enzymes, glucose-6-phosphate, can be metabolized through glycolysis or directed to alternative metabolic routes, such as the pentose phosphate pathway (PPP) to generate anabolic intermediates. HK1 contains an N-terminal mitochondrial binding domain (MBD), but its physiologic significance remains unclear. To elucidate the effect of HK1 mitochondrial dissociation on cellular metabolism, we generated mice lacking the HK1 MBD (ΔE1HK1). These mice produced a hyper-inflammatory response when challenged with lipopolysaccharide. Additionally, there was decreased glucose flux below the level of GAPDH and increased upstream flux through the PPP. The glycolytic block below GAPDH is mediated by the binding of cytosolic HK1 with S100A8/A9, resulting in GAPDH nitrosylation through iNOS. Additionally, human and mouse macrophages from conditions of low-grade inflammation, such as aging and diabetes, displayed increased cytosolic HK1 and reduced GAPDH activity. Our data indicate that HK1 mitochondrial binding alters glucose metabolism through regulation of GAPDH.


Assuntos
Glucose , Hexoquinase/metabolismo , Animais , Glucose/metabolismo , Glicólise , Hexoquinase/genética , Camundongos , Mitocôndrias/metabolismo , Via de Pentose Fosfato
5.
EMBO J ; 42(6): e112647, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36740997

RESUMO

Neurogenesis in the developing and adult brain is intimately linked to remodeling of cellular metabolism. However, it is still unclear how distinct metabolic programs and energy sources govern neural stem cell (NSC) behavior and subsequent neuronal differentiation. Here, we found that adult mice lacking the mitochondrial urea metabolism enzyme, Arginase-II (Arg-II), exhibited NSC overactivation, thereby leading to accelerated NSC pool depletion and decreased hippocampal neurogenesis over time. Mechanistically, Arg-II deficiency resulted in elevated L-arginine levels and induction of a metabolic shift from glycolysis to oxidative phosphorylation (OXPHOS) caused by impaired attachment of hexokinase-I to mitochondria. Notably, selective inhibition of OXPHOS ameliorated NSC overactivation and restored abnormal neurogenesis in Arg-II deficient mice. Therefore, Arg-II-mediated intracellular L-arginine homeostasis directly influences the metabolic fitness of neural stem cells that is essential to maintain neurogenesis with age.


Assuntos
Células-Tronco Neurais , Camundongos , Animais , Proliferação de Células , Células-Tronco Neurais/metabolismo , Neurogênese/fisiologia , Glicólise , Homeostase , Arginina/metabolismo
6.
Immunity ; 48(3): 542-555.e6, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29523440

RESUMO

Glycolysis is linked to the rapid response of memory CD8+ T cells, but the molecular and subcellular structural elements enabling enhanced glucose metabolism in nascent activated memory CD8+ T cells are unknown. We found that rapid activation of protein kinase B (PKB or AKT) by mammalian target of rapamycin complex 2 (mTORC2) led to inhibition of glycogen synthase kinase 3ß (GSK3ß) at mitochondria-endoplasmic reticulum (ER) junctions. This enabled recruitment of hexokinase I (HK-I) to the voltage-dependent anion channel (VDAC) on mitochondria. Binding of HK-I to VDAC promoted respiration by facilitating metabolite flux into mitochondria. Glucose tracing pinpointed pyruvate oxidation in mitochondria, which was the metabolic requirement for rapid generation of interferon-γ (IFN-γ) in memory T cells. Subcellular organization of mTORC2-AKT-GSK3ß at mitochondria-ER contact sites, promoting HK-I recruitment to VDAC, thus underpins the metabolic reprogramming needed for memory CD8+ T cells to rapidly acquire effector function.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Retículo Endoplasmático/metabolismo , Metabolismo Energético , Memória Imunológica , Mitocôndrias/metabolismo , Transdução de Sinais , Respiração Celular , Retículo Endoplasmático/ultraestrutura , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicólise , Membranas Intracelulares/metabolismo , Ativação Linfocitária , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Mitocôndrias/ultraestrutura , Modelos Biológicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/deficiência
7.
Proc Natl Acad Sci U S A ; 120(8): e2209177120, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36787364

RESUMO

Microglial phagocytosis is an energetically demanding process that plays a critical role in the removal of toxic protein aggregates in Alzheimer's disease (AD). Recent evidence indicates that a switch in energy production from mitochondrial respiration to glycolysis disrupts this important protective microglial function and may provide therapeutic targets for AD. Here, we demonstrate that the translocator protein (TSPO) and a member of its mitochondrial complex, hexokinase-2 (HK), play critical roles in microglial respiratory-glycolytic metabolism and phagocytosis. Pharmacological and genetic loss-of-function experiments showed that TSPO is critical for microglial respiratory metabolism and energy supply for phagocytosis, and its expression is enriched in phagocytic microglia of AD mice. Meanwhile, HK controlled glycolytic metabolism and phagocytosis via mitochondrial binding or displacement. In cultured microglia, TSPO deletion impaired mitochondrial respiration and increased mitochondrial recruitment of HK, inducing a switch to glycolysis and reducing phagocytosis. To determine the functional significance of mitochondrial HK recruitment, we developed an optogenetic tool for reversible control of HK localization. Displacement of mitochondrial HK inhibited glycolysis and improved phagocytosis in TSPO-knockout microglia. Mitochondrial HK recruitment also coordinated the inflammatory switch to glycolysis that occurs in response to lipopolysaccharide in normal microglia. Interestingly, cytosolic HK increased phagocytosis independent of its metabolic activity, indicating an immune signaling function. Alzheimer's beta amyloid drastically stimulated mitochondrial HK recruitment in cultured microglia, which may contribute to microglial dysfunction in AD. Thus, targeting mitochondrial HK may offer an immunotherapeutic approach to promote phagocytic microglial function in AD.


Assuntos
Doença de Alzheimer , Animais , Camundongos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Microglia/metabolismo , Fagocitose , Mitocôndrias/metabolismo
8.
Semin Cancer Biol ; 100: 17-27, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38494080

RESUMO

Cancer cells reprogram their metabolism to become "glycolysis-dominant," which enables them to meet their energy and macromolecule needs and enhancing their rate of survival. This glycolytic-dominancy is known as the "Warburg effect", a significant factor in the growth and invasion of malignant tumors. Many studies confirmed that members of the GLUT family, specifically HK-II from the HK family play a pivotal role in the Warburg effect, and are closely associated with glucose transportation followed by glucose metabolism in cancer cells. Overexpression of GLUTs and HK-II correlates with aggressive tumor behaviour and tumor microenvironment making them attractive therapeutic targets. Several studies have proven that the regulation of GLUTs and HK-II expression improves the treatment outcome for various tumors. Therefore, small molecule inhibitors targeting GLUT and HK-II show promise in sensitizing cancer cells to treatment, either alone or in combination with existing therapies including chemotherapy, radiotherapy, immunotherapy, and photodynamic therapy. Despite existing therapies, viable methods to target the glycolysis of cancer cells are currently lacking to increase the effectiveness of cancer treatment. This review explores the current understanding of GLUT and HK-II in cancer metabolism, recent inhibitor developments, and strategies for future drug development, offering insights into improving cancer treatment efficacy.


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Neoplasias/metabolismo , Glicólise/fisiologia , Glucose/metabolismo , Microambiente Tumoral/genética
9.
Plant J ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995679

RESUMO

Bacterial leaf streak (BLS), caused by Xanthomonas oryzae pv. oryzicola (Xoc), is a major bacterial disease in rice. Transcription activator-like effectors (TALEs) from Xanthomonas can induce host susceptibility (S) genes and facilitate infection. However, knowledge of the function of Xoc TALEs in promoting bacterial virulence is limited. In this study, we demonstrated the importance of Tal10a for the full virulence of Xoc. Through computational prediction and gene expression analysis, we identified the hexokinase gene OsHXK5 as a host target of Tal10a. Tal10a directly binds to the gene promoter region and activates the expression of OsHXK5. CRISPR/Cas9-mediated gene editing in the effector binding element (EBE) of OsHXK5 significantly increases rice resistance to Xoc, while OsHXK5 overexpression enhances the susceptibility of rice plants and impairs rice defense responses. Moreover, simultaneous editing of the promoters of OsSULTR3;6 and OsHXK5 confers robust resistance to Xoc in rice. Taken together, our findings highlight the role of Tal10a in targeting OsHXK5 to promote infection and suggest that OsHXK5 represents a potential target for engineering rice resistance to Xoc.

10.
Eur J Immunol ; : e2350954, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837415

RESUMO

Hexokinases (HKs) control the first step of glucose catabolism. A switch of expression from liver HK (glucokinase, GCK) to the tumor isoenzyme HK2 is observed in hepatocellular carcinoma progression. Our prior work revealed that HK isoenzyme switch in hepatocytes not only regulates hepatic metabolic functions but also modulates innate immunity and sensitivity to Natural Killer (NK) cell cytotoxicity. This study investigates the impact of HK2 expression and its mitochondrial binding on the resistance of human liver cancer cells to NK-cell-induced cytolysis. We have shown that HK2 expression induces resistance to NK cell cytotoxicity in a process requiring mitochondrial binding of HK2. Neither HK2 nor GCK expression affects target cells' ability to activate NK cells. In contrast, mitochondrial binding of HK2 reduces effector caspase 3/7 activity both at baseline and upon NK-cell activation. Furthermore, HK2 tethering to mitochondria enhances their resistance to cytochrome c release triggered by tBID. These findings indicate that HK2 mitochondrial binding in liver cancer cells is an intrinsic resistance factor to cytolysis and an escape mechanism from immune surveillance.

11.
FASEB J ; 38(6): e23556, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38498348

RESUMO

PARP-1 over-activation results in cell death via excessive PAR generation in different cell types, including neurons following brain ischemia. Glycolysis, mitochondrial function, and redox balance are key cellular processes altered in brain ischemia. Studies show that PAR generated after PARP-1 over-activation can bind hexokinase-1 (HK-1) and result in glycolytic defects and subsequent mitochondrial dysfunction. HK-1 is the neuronal hexokinase and catalyzes the first reaction of glycolysis, converting glucose to glucose-6-phosphate (G6P), a common substrate for glycolysis, and the pentose phosphate pathway (PPP). PPP is critical in maintaining NADPH and GSH levels via G6P dehydrogenase activity. Therefore, defects in HK-1 will not only decrease cellular bioenergetics but will also cause redox imbalance due to the depletion of GSH. In brain ischemia, whether PAR-mediated inhibition of HK-1 results in bioenergetics defects and redox imbalance is not known. We used oxygen-glucose deprivation (OGD) in mouse cortical neurons to mimic brain ischemia in neuronal cultures and observed that PARP-1 activation via PAR formation alters glycolysis, mitochondrial function, and redox homeostasis in neurons. We used pharmacological inhibition of PARP-1 and adenoviral-mediated overexpression of wild-type HK-1 (wtHK-1) and PAR-binding mutant HK-1 (pbmHK-1). Our data show that PAR inhibition or overexpression of HK-1 significantly improves glycolysis, mitochondrial function, redox homeostasis, and cell survival in mouse cortical neurons exposed to OGD. These results suggest that PAR binding and inhibition of HK-1 during OGD drive bioenergetic defects in neurons due to inhibition of glycolysis and impairment of mitochondrial function.


Assuntos
Isquemia Encefálica , Oxigênio , Camundongos , Animais , Oxigênio/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Glucose/metabolismo , Isquemia Encefálica/metabolismo , Glicólise , Neurônios/metabolismo , Oxirredução
12.
Mol Plant Microbe Interact ; 37(1): 25-35, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37717227

RESUMO

The potato cyst nematode (Globodera rostochiensis) is an obligate root pathogen of potatoes. G. rostochiensis encodes several highly expanded effector gene families, including the Gr4D06 family; however, little is known about the function of this effector family. We cloned four 29D09 genes from G. rostochiensis (named Gr29D09v1/v2/v3/v4) that share high sequence similarity and are homologous to the Hg29D09 and Hg4D06 effector genes from the soybean cyst nematode (Heterodera glycines). Phylogenetic analysis revealed that Gr29D09 genes belong to a subgroup of the Gr4D06 family. We showed that Gr29D09 genes are expressed exclusively within the nematode's dorsal gland cell and are dramatically upregulated in parasitic stages, indicating involvement of Gr29D09 effectors in nematode parasitism. Transgenic potato lines overexpressing Gr29D09 variants showed increased susceptibility to G. rostochiensis. Transient expression assays in Nicotiana benthamiana demonstrated that Gr29D09v3 could suppress reactive oxygen species (ROS) production and defense gene expression induced by flg22 and cell death mediated by immune receptors. These results suggest a critical role of Gr29D09 effectors in defense suppression. The use of affinity purification coupled with nanoliquid chromatography-tandem mass spectrometry identified potato hexokinase 1 (StHXK1) as a candidate target of Gr29D09. The Gr29D09-StHXK1 interaction was further confirmed using in planta protein-protein interaction assays. Plant HXKs have been implicated in defense regulation against pathogen infection. Interestingly, we found that StHXK1 could enhance flg22-induced ROS production, consistent with a positive role of plant HXKs in defense. Altogether, our results suggest that targeting StHXK1 by Gr29D09 effectors may impair the positive function of StHXK1 in plant immunity, thereby aiding nematode parasitism. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.


Assuntos
Nematoides , Solanum tuberosum , Tylenchoidea , Animais , Hexoquinase/genética , Espécies Reativas de Oxigênio , Filogenia , Proteínas/genética , Tylenchoidea/fisiologia
13.
Glia ; 72(2): 396-410, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37909251

RESUMO

Neuropathic pain is a complex pain condition accompanied by prominent neuroinflammation involving activation of both central and peripheral immune cells. Metabolic switch to glycolysis is an important feature of activated immune cells. Hexokinase 2 (HK2), a key glycolytic enzyme enriched in microglia, has recently been shown important in regulating microglial functions. Whether and how HK2 is involved in neuropathic pain-related neuroinflammation remains unknown. Using a HK2-tdTomato reporter line, we found that HK2 was prominently elevated in spinal microglia. Pharmacological inhibition of HK2 effectively alleviated nerve injury-induced acute mechanical pain. However, selective ablation of Hk2 in microglia reduced microgliosis in the spinal dorsal horn (SDH) with little analgesic effects. Further analyses showed that nerve injury also significantly induced HK2 expression in dorsal root ganglion (DRG) macrophages. Deletion of Hk2 in myeloid cells, including both DRG macrophages and spinal microglia, led to the alleviation of mechanical pain during the first week after injury, along with attenuated microgliosis in the ipsilateral SDH, macrophage proliferation in DRGs, and suppressed inflammatory responses in DRGs. These data suggest that HK2 plays an important role in regulating neuropathic pain-related immune cell responses at acute phase and that HK2 contributes to neuropathic pain onset primarily through peripheral monocytes and DRG macrophages rather than spinal microglia.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Humanos , Microglia/metabolismo , Hexoquinase/metabolismo , Hexoquinase/farmacologia , Doenças Neuroinflamatórias , Hiperalgesia/metabolismo , Macrófagos/metabolismo , Neuralgia/metabolismo , Gânglios Espinais/metabolismo , Medula Espinal/metabolismo , Traumatismos dos Nervos Periféricos/metabolismo
14.
Immunology ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804253

RESUMO

Retinopathy of prematurity (ROP) is a retinal disease-causing retinal neovascularization that can lead to blindness. Oxygen-induced retinopathy (OIR) is a widely used ROP animal model. Icariin (ICA) has anti-oxidative and anti-inflammation properties; however, whether ICA has a regulatory effect on OIR remains unclear. In this study, ICA alleviated pathological neovascularization, microglial activation and blood-retina barrier (BRB) damage in vivo. Further results indicated that endothelial cell tube formation, migration and proliferation were restored by ICA treatment in vitro. Proteomic microarrays and molecular mimicry revealed that ICA can directly bind to hexokinase 2 (HK2) and decrease HK2 protein expression in vivo and in vitro. In addition, ICA inhibited the AKT/mTOR/HIF1α pathway activation. The effects of ICA on pathological neovascularization, microglial activation and BRB damage disappeared after HK2 overexpression in vivo. Similarly, the endothelial cell function was revised after HK2 overexpression. HK2 overexpression reversed ICA-induced AKT/mTOR/HIF1α pathway inhibition in vivo and in vitro. Therefore, ICA prevented pathological angiogenesis in OIR in an HK2-dependent manner, implicating ICA as a potential therapeutic agent for ROP.

15.
Br J Haematol ; 204(5): 2040-2048, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38415930

RESUMO

The hexokinase (HK) enzyme plays a key role in red blood cell energy production. Hereditary non-spherocytic haemolytic anaemia (HNSHA) caused by HK deficiency is a rare disorder with only 12 different disease-associated variants identified. Here, we describe the clinical features and genotypes of four previously unreported patients with hexokinase 1 (HK1)-related HNSHA, yielding two novel truncating HK1 variants. The patients' phenotypes varied from mild chronic haemolytic anaemia to severe infantile-onset transfusion-dependent anaemia. Three of the patients had mild haemolytic disease caused by the common HK1 promoter c.-193A>G variant combined with an intragenic HK1 variant, emphasizing the importance of including this promoter variant in the haemolytic disease gene panels. HK activity was normal in a severely affected patient with a homozygous HK1 c.2599C>T, p.(His867Tyr) variant, but the affinity for ATP was reduced, hampering the HK function. In cases of HNSHA, kinetic studies should be considered in the functional studies of HK. We reviewed the literature of previously published patients to provide better insight into this rare disease and add to the understanding of genotype-phenotype correlation.


Assuntos
Anemia Hemolítica Congênita não Esferocítica , Hexoquinase , Regiões Promotoras Genéticas , Humanos , Hexoquinase/genética , Hexoquinase/deficiência , Feminino , Masculino , Anemia Hemolítica Congênita não Esferocítica/genética , Lactente , Alelos , Pré-Escolar , Fenótipo , Criança , Genótipo
16.
Cytokine ; 176: 156535, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38325141

RESUMO

Increasing evidence suggests the oncogenic role of missense mutation (AKT1-E17K) of AKT1 gene in meningiomas. Upon investigating the connection between the pro-tumorigenic role of AKT1-E17K and cellular metabolic adaptations, elevated levels of glycolytic enzyme hexokinase 2 (HK2) was observed in meningioma patients with AKT1-E17K compared to patients harboring wild-type AKT1. In vitro experiments also suggested higher HK2 levels and its activity in AKT1-E17K cells. Treatment with the conventional drug of choice AZD5363 (a pan AKT inhibitor) enhanced cell death and diminished HK2 levels in AKT1 mutants. Given the role of AKT phosphorylation in eliciting inflammatory responses, we observed increased levels of inflammatory mediators (IL-1ß, IL6, IL8, and TLR4) in AKT1-E17K cells compared to AKT1-WT cells. Treatment with AKT or HK2 inhibitors dampened the heightened levels of inflammatory markers in AKT1-E17K cells. As AKT and HK2 regulates redox homeostasis, diminished ROS generation concomitant with increased levels of NF-E2- related factor 2 (Nrf2) and superoxide dismutase 1 (SOD1) were observed in AKT1-E17K cells. Increased sensitivity of AKT1-E17K cells to AZD5363 in the presence of HK2 inhibitor Lonidamine was reversed upon treatment with ROS inhibitor NAC. By affecting metabolism, inflammation, and redox homeostasis AKT1-E17K confers a survival advantage in meningioma cells. Our findings suggest that targeting AKT-HK2 cross-talk to induce ROS-dependent cell death could be exploited as novel therapeutic approach in meningiomas.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Mutação com Ganho de Função , Hexoquinase/genética , Hexoquinase/metabolismo , Neoplasias Meníngeas/genética , Meningioma/genética , Estresse Oxidativo/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio
17.
J Exp Bot ; 75(13): 3818-3834, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38642398

RESUMO

Plant growth depends on sugar production and export by photosynthesizing source leaves and sugar allocation and import by sink tissues (grains, roots, stems, and young leaves). Photosynthesis and sink demand are tightly coordinated through metabolic (substrate, allosteric) feedback and signalling (sugar, hormones) mechanisms. Sugar signalling integrates sugar production with plant development and environmental cues. In C3 plants (e.g. wheat and rice), it is well documented that sugar accumulation in source leaves, due to source-sink imbalance, negatively feeds back on photosynthesis and plant productivity. However, we have a limited understanding about the molecular mechanisms underlying those feedback regulations, especially in C4 plants (e.g. maize, sorghum, and sugarcane). Recent work with the C4 model plant Setaria viridis suggested that C4 leaves have different sugar sensing thresholds and behaviours relative to C3 counterparts. Addressing this research priority is critical because improving crop yield requires a better understanding of how plants coordinate source activity with sink demand. Here we review the literature, present a model of action for sugar sensing in C4 source leaves, and suggest ways forward.


Assuntos
Folhas de Planta , Açúcares , Folhas de Planta/metabolismo , Açúcares/metabolismo , Fotossíntese , Setaria (Planta)/metabolismo , Setaria (Planta)/crescimento & desenvolvimento , Metabolismo dos Carboidratos
18.
Stem Cells ; 41(6): 628-642, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-36951300

RESUMO

Migration of mesenchymal stem cells (MSCs) to the site of injury is crucial in transplantation therapy. Studies have shown that cell migration is regulated by the cellular microenvironment and accompanied by changes in cellular metabolism. However, limited information is available about the relationship between MSC migration and cellular metabolism. Here, we show that basic fibroblast growth factor (bFGF) promotes the migration of MSCs with high levels of glycolysis and high expression of hexokinase 2 (HK2), a rate-limiting enzyme in glycolysis. The enhancement of glycolysis via the activation of HK2 expression promoted the migration of MSCs, whereas the inhibition of glycolysis, but not of oxidative phosphorylation, inhibited the bFGF-induced migration of these cells. Furthermore, bFGF enhanced glycolysis by increasing HK2 expression, which consequently promoted ß-catenin accumulation, and the inhibition of glycolysis inhibited the bFGF-induced accumulation of ß-catenin. When the accumulation of glycolytic intermediates was altered, phosphoenolpyruvate was found to be directly involved in the regulation of ß-catenin expression and activation, suggesting that bFGF regulates ß-catenin signaling through glycolytic intermediates. Moreover, transplantation with HK2-overexpressing MSCs significantly improved the effect of cell therapy on skull injury in rats. In conclusion, we propose a novel glycolysis-dependent ß-catenin signaling regulatory mechanism and provide an experimental and theoretical basis for the clinical application of MSCs.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Células-Tronco Mesenquimais , Animais , Ratos , beta Catenina/metabolismo , Movimento Celular , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glicólise , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt
19.
Arch Biochem Biophys ; 756: 110021, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38697344

RESUMO

The physiological efficiency of cells largely depends on the possibility of metabolic adaptations to changing conditions, especially on the availability of nutrients. Central carbon metabolism has an essential role in cellular function. In most cells is based on glucose, which is the primary energy source, provides the carbon skeleton for the biosynthesis of important cell macromolecules, and acts as a signaling molecule. The metabolic flux between pathways of carbon metabolism such as glycolysis, pentose phosphate pathway, and mitochondrial oxidative phosphorylation is dynamically adjusted by specific cellular economics responding to extracellular conditions and intracellular demands. Using Saccharomyces cerevisiae yeast cells and potentially similar fermentable carbon sources i.e. glucose and fructose we analyzed the parameters concerning the metabolic status of the cells and connected with them alteration in cell reproductive potential. Those parameters were related to the specific metabolic network: the hexose uptake - glycolysis and activity of the cAMP/PKA pathway - pentose phosphate pathway and biosynthetic capacities - the oxidative respiration and energy generation. The results showed that yeast cells growing in a fructose medium slightly increased metabolism redirection toward respiratory activity, which decreased pentose phosphate pathway activity and cellular biosynthetic capabilities. These differences between the fermentative metabolism of glucose and fructose, lead to long-term effects, manifested by changes in the maximum reproductive potential of cells.


Assuntos
Metabolismo Energético , Fermentação , Frutose , Glucose , Glicólise , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Via de Pentose Fosfato
20.
BMC Cancer ; 24(1): 571, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720279

RESUMO

BACKGROUND: Glycometabolism and lipid metabolism are critical in cancer metabolic reprogramming. The primary aim of this study was to develop a prognostic model incorporating glycometabolism and lipid metabolism-related genes (GLRGs) for accurate prognosis assessment in patients with endometrial carcinoma (EC). METHODS: Data on gene expression and clinical details were obtained from publicly accessible databases. GLRGs were obtained from the Genecards database. Through nonnegative matrix factorization (NMF) clustering, molecular groupings with various GLRG expression patterns were identified. LASSO Cox regression analysis was employed to create a prognostic model. Use rich algorithms such as GSEA, GSVA, xCELL ssGSEA, EPIC,CIBERSORT, MCPcounter, ESTIMATE, TIMER, TIDE, and Oncoppredict to analyze functional pathway characteristics of the forecast signal, immune status, anti-tumor therapy, etc. The expression was assessed using Western blot and quantitative real-time PCR techniques. A total of 113 algorithm combinations were combined to screen out the most significant GLRGs in the signature for in vitro experimental verification, such as colony formation, EdU cell proliferation, wound healing, apoptosis, and Transwell assays. RESULTS: A total of 714 GLRGs were found, and 227 of them were identified as prognostic-related genes. And ten GLRGs (AUP1, ESR1, ERLIN2, ASS1, OGDH, BCKDHB, SLC16A1, HK2, LPCAT1 and PGR-AS1) were identified to construct the prognostic model of patients with EC. Based on GLRGs, the risk model's prognosis and independent prognostic value were established. The signature of GLRGs exhibited a robust correlation with the infiltration of immune cells and the sensitivity to drugs. In cytological experiments, we selected HK2 as candidate gene to verify its value in the occurrence and development of EC. Western blot and qRT-PCR revealed that HK2 was substantially expressed in EC cells. According to in vitro experiments, HK2 knockdown can increase EC cell apoptosis while suppressing EC cell migration, invasion, and proliferation. CONCLUSION: The GLRGs signature constructed in this study demonstrated significant prognostic value for patients with endometrial carcinoma, thereby providing valuable guidance for treatment decisions.


Assuntos
Neoplasias do Endométrio , Metabolismo dos Lipídeos , Humanos , Feminino , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/metabolismo , Prognóstico , Metabolismo dos Lipídeos/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células/genética , Apoptose/genética , Linhagem Celular Tumoral , Perfilação da Expressão Gênica
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