RESUMEN
Acute liver injury (ALI) is a common life-threatening condition with a high mortality rate due to liver disease-related death. However, current therapeutic interventions for ALI remain ineffective, and the development of effective novel therapies is urgently needed. Liver samples from patients with drug-induced ALI were collected to detect adenosine kinase (ADK) expression. Male C57BL/6 J mice, hepatocyte-specific ADK knockout (ADKHKO) mice, and their controls (ADKf/f) were exposed to acetaminophen (APAP) and other treatments to investigate the mechanisms of APAP-related ALI. ADK expression was significantly decreased in APAP-injured livers. Hepatocyte-specific ADK deficiency exacerbated APAP-induced ALI, while a gain-of-function approach delivering AAV-ADK, markedly alleviated APAP-induced ALI, as indicated by changes in alanine aminotransferases (ALT) levels, aspartate aminotransferase (AST) levels, neutrophil infiltration and hepatocyte death. This study showed that ADK played a critical role in ALI by activating autophagy through two signaling pathways, the adenosine monophosphate-activated protein kinase (AMPK)-mTOR pathway and the adenosine receptor A1 (ADORA1)-Akt-mTOR pathway. Furthermore, we found that metformin upregulated ADK expression in hepatocytes and protected against APAP-induced ALI. These results demonstrate that ADK is critical in protecting against APAP-induced ALI and that developing therapeutics targeting ADK-adenosine-ADORA1 is a new approach for ALI treatment. Metformin is a potential candidate for preventing ALI by upregulating ADK.
Asunto(s)
Acetaminofén , Adenosina Quinasa , Autofagia , Enfermedad Hepática Inducida por Sustancias y Drogas , Hepatocitos , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Acetaminofén/efectos adversos , Adenosina Quinasa/metabolismo , Adenosina Quinasa/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
AIM: To investigate the effects of adenosine kinase (ADK), a key enzyme in determining intracellular adenosine levels, on ß cells, and their underlying mechanism. METHODS: Genetic animal models and transgenic immortalized cells were applied to study the effect of ADK on islet beta-cell proliferation and function. The beta-cell mass and response to glucose were measured in vivo using mice with beta-cell-specific ADK overexpression, and in vitro using ADK-overexpressed immortalized beta-cell. RESULTS: The expression of ADK in human islets at high abundance, especially in ß cells, was decreased during the process of ß-cell proliferation. Additionally, a transgenic mouse model (ADKtg/tg /Mip-Cre) was generated wherein the mouse Insulin1 gene promoter specifically overexpressed ADK in pancreatic ß cells. The ADKtg/tg /Mip-Cre model exhibited impaired glucose tolerance, decreased fasting plasma insulin, loss of ß-cell mass, and inhibited ß-cell proliferation. Proteomic analysis revealed that ADK overexpression inhibited the expression of several proteins that promote cell proliferation and insulin secretion. Upregulating ADK in the ß-cell line inhibited the expression of ß-cell related regulatory molecules, including FoxO1, Appl1, Pxn, Pdx-1, Creb and Slc16a3. Subsequent in vitro experiments indicated that the inhibition of ß-cell proliferation and the decreased expression of Pdx-1, Creb and Slc16a3 were rescued by DNA methyltransferase 3A (DNMT3A) knockdown in ß cells. CONCLUSION: In this study, we found that the overexpression of ADK decreased the expression of several genes that regulate ß cells, resulting in the inhibition of ß-cell proliferation and dysfunction by upregulating the expression of DNMT3A.
Asunto(s)
Adenosina Quinasa , Proliferación Celular , ADN (Citosina-5-)-Metiltransferasas , ADN Metiltransferasa 3A , Células Secretoras de Insulina , Ratones Transgénicos , Regulación hacia Arriba , Células Secretoras de Insulina/metabolismo , Animales , Ratones , Humanos , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Masculino , Secreción de Insulina , Insulina/metabolismoRESUMEN
Adenosine kinase deficiency (OMIM #614300) is a type of inborn errors of metabolism with multiorgan symptoms primarily neurological disorders, hepatic impairment, global developmental delay, and mild dysmorphism. The genetic causes of adenosine kinase deficiency are homozygous or compound heterozygous loss-of-function variants of ADK. To date, fewer than 25 cases of adenosine kinase deficiency have been reported worldwide and none have been reported in China. In this research, trio whole-exome sequencing (Trio-WES) identified a novel homozygous ADK (NM_001123.4) out-of-frame deletion, c.518_519delCA (p.Thr173Serfs*15), in a Chinese patient with rare phenotypes of sepsis, metabolites disruption and neutrophil dysfunction. This variant was dysfunctional, with marked reduction of ADK level in both the patient's peripheral blood and cells transfected with the corresponding variant. Additionally, metabolomics detected by high-throughput mass spectrometry showed disturbances in the methionine (Met) and energy pathway. RNA sequencing (RNA-seq) of the patient's peripheral blood suggested a defective anti-inflammatory response characterized by impaired neutrophil activation, migration, and degranulation, which might be the primary cause for the sepsis. To our knowledge, we identified the first Chinese patient of adenosine kinase deficiency with a novel homozygous out-of-frame deletion in ADK causing multiorgan disorders, metabolites disruption, rare phenotypes of sepsis, and neutrophil dysfunction. Our findings broaden the genetic spectrum and pathogenic mechanisms of adenosine kinase deficiency.
Asunto(s)
Adenosina Quinasa , Homocigoto , Neutrófilos , Fenotipo , Sepsis , Humanos , Sepsis/genética , Neutrófilos/metabolismo , Adenosina Quinasa/genética , Adenosina Quinasa/deficiencia , Masculino , Secuenciación del Exoma , Eliminación de Secuencia , FemeninoRESUMEN
PURPOSE: Temporal lobe epilepsy (TLE) has a high risk of developing drug resistant and cognitive comorbidities. Adenosine has potential anticonvulsant effects as an inhibitory neurotransmitter, but drugs targeting its receptors and metabolic enzyme has inevitable side effects. Therefore, we investigated adenosine augmentation therapy for seizure control and cognitive comorbidities in TLE animals. METHODS: Using lentiviral vectors coexpressing miRNA inhibiting the expression of adenosine kinase (ADK), we produced ADK--rMSC (ADK knockdown rat mesenchymal stem cell). ADK--rMSC and LV-con-rMSC (rMSC transduced by randomized scrambled control sequence) were transplanted into the hippocampus of TLE rat respectively. ADK-+DPCPX group was transplanted with ADK--rMSC and intraperitoneally injected with DPCPX (adenosine A1 receptor antagonist). Seizure behavior, EEG, CA1 pyramidal neuron apoptosis, and behavior in Morris water maze and novel object recognition test were studied RESULTS: Adenosine concentration in the supernatants of 105 ADK--rMSCs was 13.8 ng/ml but not detectable in LV-con-rMSCs. ADK--rMSC (n = 11) transplantation decreased spontaneous recurrent seizure (SRS) duration compared to LV-con-rMSC (n = 11, P < 0.05). CA1 neuron apoptosis was decreased in ADK--rMSC (n = 3, P < 0.05). ADK--rMSC (n = 11) improved the Morris water maze performance of TLE rats compared to LV-con-rMSC (n = 11, escape latency, P < 0.01; entries in target quadrant, P < 0.05). The effect of ADK--rMSC on neuron apoptosis and spatial memory were counteracted by DPCPX. However, ADK--rMSC didn't improve the performance in novel object recognition test. CONCLUSION: Adenosine augmentation-based ADK--rMSC transplantation is a promising therapeutic candidate for TLE and related cognitive comorbidities.
Asunto(s)
Disfunción Cognitiva , Epilepsia del Lóbulo Temporal , Trasplante de Células Madre Mesenquimatosas , Ratas , Animales , Epilepsia del Lóbulo Temporal/terapia , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Adenosina/metabolismo , Convulsiones/terapia , Disfunción Cognitiva/genética , Disfunción Cognitiva/terapiaRESUMEN
Adenosine kinase (ADK), the major adenosine-metabolizing enzyme, plays a key role in brain development and disease. In humans, mutations in the Adk gene have been linked to developmental delay, stunted growth, and intellectual disability. To better understand the role of ADK in brain development, it is important to dissect the specific roles of the two isoforms of the enzyme expressed in the cytoplasm (ADK-S) and cell nucleus (ADK-L). We, therefore, studied brain development in Adk-tg transgenic mice, which only express ADK-S in the absence of ADK-L throughout development. In the mutant animals, we found a reduction in the overall brain, body size, and weight during fetal and postnatal development. As a major developmental abnormality, we found a profound change in the foliation pattern of the cerebellum. Strikingly, our results indicated aberrant Purkinje cells arborization at P9 and accelerated cell death at P6 and P9. We found defects in cerebellar cell proliferation and migration using a bromodeoxyuridine (BrdU)-based cell proliferation assay at postnatal day 7. Our data demonstrate that dysregulation of ADK expression during brain development profoundly affects brain growth and differentiation.
Asunto(s)
Adenosina Quinasa , Encéfalo , Ratones , Animales , Humanos , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Encéfalo/metabolismo , Ratones Transgénicos , Cerebelo/metabolismo , Isoformas de Proteínas/metabolismoRESUMEN
Resistance to traditional antiepileptic drugs is a major challenge in chronic epilepsy treatment. MicroRNA-based gene therapy is a promising alternative but has demonstrated limited efficacy due to poor blood-brain barrier permeability, cellular uptake, and targeting efficiency. Adenosine is an endogenous antiseizure agent deficient in the epileptic brain due to elevated adenosine kinase (ADK) activity in reactive A1 astrocytes. We designed a nucleic acid nanoantiepileptic drug (tFNA-ADKASO@AS1) based on a tetrahedral framework nucleic acid (tFNA), carrying an antisense oligonucleotide targeting ADK (ADKASO) and A1 astrocyte-targeted peptide (AS1). This tFNA-ADKASO@AS1 construct effectively reduced brain ADK, increased brain adenosine, mitigated aberrant mossy fiber sprouting, and reduced the recurrent spontaneous epileptic spike frequency in a mouse model of chronic temporal lobe epilepsy. Further, the treatment did not induce any neurotoxicity or major organ damage. This work provides proof-of-concept for a novel antiepileptic drug delivery strategy and for endogenous adenosine as a promising target for gene-based modulation.
Asunto(s)
Epilepsia , Ácidos Nucleicos , Ratones , Animales , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Astrocitos/metabolismo , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Ácidos Nucleicos/metabolismo , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Epilepsia/metabolismo , Adenosina/farmacologíaRESUMEN
Pro-inflammatory and reparative macrophages are crucial in clearing necrotic myocardium and promoting cardiac repair after myocardial infarction (MI), respectively. Extracellular adenosine has been demonstrated to modulate macrophage polarization through adenosine receptors. However, the role of intracellular adenosine in macrophage polarization has not been explored and adenosine kinase (ADK) is a major enzyme regulating intracellular adenosine levels. Here, we aimed to elucidate the role of ADK in macrophage polarization and its subsequent impact on MI. We demonstrated that ADK was upregulated in bone marrow-derived macrophages (BMDMs) after IL-4 treatment and was highly expressed in the infarct area at day 7 post-MI, especially in macrophages. Compared with wild-type mice, myeloid-specific Adk knockout mice showed increased infarct size, limited myofibroblast differentiation, reduced collagen deposition and more severe cardiac dysfunction after MI, which was related to impaired reparative macrophage phenotype in MI tissue. We found that ADK deletion or inhibition significantly decreased the expression of reparative genes, such as Arg1, Ym1, Fizz1, and Cd206 in BMDMs after IL-4 treatment. The increased intracellular adenosine due to Adk deletion inhibited transmethylation reactions and decreased the trimethylation of H3K4 in BMDMs after IL-4 treatment. Mechanistically, we demonstrated that Adk deletion suppressed reparative macrophage phenotype through decreased IRF4 expression, which resulted from reduced levels of H3K4me3 on the Irf4 promotor. Together, our study reveals that ADK exerts a protective effect against MI by promoting reparative macrophage polarization through epigenetic mechanisms.
Asunto(s)
Adenosina Quinasa , Infarto del Miocardio , Ratones , Animales , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Interleucina-4/genética , Macrófagos/metabolismo , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Fenotipo , Ratones Noqueados , Ratones Endogámicos C57BLRESUMEN
BACKGROUND & AIMS: Nonalcoholic fatty liver disease is highly associated with obesity and progresses to nonalcoholic steatohepatitis when the liver develops overt inflammatory damage. While removing adenosine in the purine salvage pathway, adenosine kinase (ADK) regulates methylation reactions. We aimed to study whether hepatocyte ADK functions as an obesogenic gene/enzyme to promote excessive fat deposition and liver inflammation. METHODS: Liver sections of human subjects were examined for ADK expression using immunohistochemistry. Mice with hepatocyte-specific ADK disruption or overexpression were examined for hepatic fat deposition and inflammation. Liver lipidomics, hepatocyte RNA sequencing (RNA-seq), and single-cell RNA-seq for liver nonparenchymal cells were performed to analyze ADK regulation of hepatocyte metabolic responses and hepatocyte-nonparenchymal cells crosstalk. RESULTS: Whereas patients with nonalcoholic fatty liver disease had increased hepatic ADK levels, mice with hepatocyte-specific ADK disruption displayed decreased hepatic fat deposition on a chow diet and were protected from diet-induced excessive hepatic fat deposition and inflammation. In contrast, mice with hepatocyte-specific ADK overexpression displayed increased body weight and adiposity and elevated degrees of hepatic steatosis and inflammation compared with control mice. RNA-seq and epigenetic analyses indicated that ADK increased hepatic DNA methylation and decreased hepatic Ppara expression and fatty acid oxidation. Lipidomic and single-cell RNA-seq analyses indicated that ADK-driven hepatocyte factors, due to mitochondrial dysfunction, enhanced macrophage proinflammatory activation in manners involving increased expression of stimulator of interferon genes. CONCLUSIONS: Hepatocyte ADK functions to promote excessive fat deposition and liver inflammation through suppressing hepatocyte fatty acid oxidation and producing hepatocyte-derived proinflammatory mediators. Therefore, hepatocyte ADK is a therapeutic target for managing obesity and nonalcoholic fatty liver disease.
Asunto(s)
Hepatitis , Enfermedad del Hígado Graso no Alcohólico , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Hepatocitos/metabolismo , Hepatitis/metabolismo , Hígado/metabolismo , Obesidad/metabolismo , Inflamación/metabolismo , Ácidos Grasos/metabolismo , Ratones Endogámicos C57BL , Dieta Alta en GrasaRESUMEN
OBJECTIVE: Vagus nerve stimulation (VNS) is an alternative treatment option for individuals with refractory epilepsy, with nearly 40% of patients showing no benefit after VNS and only 6%-8% achieving seizure freedom. It is presently unclear why some patients respond to treatment and others do not. Therefore, identification of biomarkers to predict efficacy of VNS is of utmost importance. The objective of this study was to explore whether genetic variations in genes involved in adenosine kinase (ADK), ecto-5'-nucleotidase (NT5E), and adenosine A1 receptor (A1R) are linked to outcome of VNS in patients with refractory epilepsy. METHODS: Thirty single-nucleotide polymorphisms (SNPs), including 9 in genes encoding ADK, 3 in genes encoding NT5E, and 18 in genes encoding A1R, were genotyped in 194 refractory epilepsy patients who underwent VNS. The chi-square test and binary logistic regression were used to determine associations between genetic differences and VNS efficacy. RESULTS: A significant association between ADK SNPs rs11001109, rs7899674, and rs946185 and seizure reduction with VNS was found. Regardless of sex, age, seizure frequency and type, antiseizure drug use, etiology, and prior surgical history, all patients (10/10 patients [100%]) with minor allele homozygosity at rs11001109 (genotype AA) or rs946185 (AA) achieved > 50% seizure reduction and 4 patients (4/10 [40%]) achieved seizure freedom. VNS therapy demonstrated higher efficacy among carriers of minor allele rs7899674 (CG + GG) (68.3% vs 48.8% for patients with major allele homozygosity). CONCLUSIONS: Homozygous ADK SNPs rs11001109 (AA) and rs946185 (AA), as well as minor allele rs7899674 (CG + GG), may serve as useful biomarkers for prediction of VNS therapy outcome.
Asunto(s)
Adenosina Quinasa , Epilepsia Refractaria , Epilepsia , Estimulación del Nervio Vago , Adenosina Quinasa/genética , Biomarcadores , Epilepsia Refractaria/genética , Epilepsia Refractaria/terapia , Epilepsia/tratamiento farmacológico , Humanos , Polimorfismo de Nucleótido Simple/genética , Convulsiones/terapia , Resultado del Tratamiento , Nervio VagoRESUMEN
Adenosine kinase (ADK) is the key regulator of adenosine and catalyzes the metabolism of adenosine to 5'-adenosine monophosphate. The enzyme exists in two isoforms: a long isoform (ADK-long, ADK-L) and a short isoform (ADK-short, ADK-S). The two isoforms are developmentally regulated and are differentially expressed in distinct subcellular compartments with ADK-L localized in the nucleus and ADK-S localized in the cytoplasm. The nuclear localization of ADK-L and its biochemical link to the transmethylation pathway suggest a specific role for gene regulation via epigenetic mechanisms. Recent evidence reveals an adenosine receptor-independent role of ADK in determining the global methylation status of DNA and thereby contributing to epigenomic regulation. Here we summarize recent progress in understanding the biochemical interactions between adenosine metabolism by ADK-L and epigenetic modifications linked to transmethylation reactions. This review will provide a comprehensive overview of ADK-associated changes in DNA methylation in developmental, as well as in pathological conditions including brain injury, epilepsy, vascular diseases, cancer, and diabetes. Challenges in investigating the epigenetic role of ADK for therapeutic gains are briefly discussed.
Asunto(s)
Adenosina Quinasa/metabolismo , Lesiones Encefálicas/metabolismo , Epigénesis Genética/genética , Epilepsia/metabolismo , Adenosina Quinasa/genética , Animales , Metilación de ADN/genética , Metilación de ADN/fisiología , Epilepsia/genética , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/fisiología , HumanosRESUMEN
Adenosine acts as a neuromodulator and metabolic regulator of the brain through receptor dependent and independent mechanisms. In the brain, adenosine is tightly controlled through its metabolic enzyme adenosine kinase (ADK), which exists in a cytoplasmic (ADK-S) and nuclear (ADK-L) isoform. We recently discovered that ADK-L contributes to adult hippocampal neurogenesis regulation. Although the cerebellum (CB) is a highly plastic brain area with a delayed developmental trajectory, little is known about the role of ADK. Here, we investigated the developmental profile of ADK expression in C57BL/6 mice CB and assessed its role in developmental and proliferative processes. We found high levels of ADK-L during cerebellar development, which was maintained into adulthood. This pattern contrasts with that of the cerebrum, in which ADK-L expression is gradually downregulated postnatally and largely restricted to astrocytes in adulthood. Supporting a functional role in cell proliferation, we found that the ADK inhibitor 5-iodotubericine (5-ITU) reduced DNA synthesis of granular neuron precursors in a concentration-dependent manner in vitro In the developing CB, immunohistochemical studies indicated ADK-L is expressed in immature Purkinje cells and granular neuron precursors, whereas in adulthood, ADK is absent from Purkinje cells, but widely expressed in mature granule neurons and their molecular layer (ML) processes. Furthermore, ADK-L is expressed in developing and mature Bergmann glia in the Purkinje cell layer, and in astrocytes in major cerebellar cortical layers. Together, our data demonstrate an association between neuronal ADK expression and developmental processes of the CB, which supports a functional role of ADK-L in the plasticity of the CB.
Asunto(s)
Adenosina Quinasa , Cerebelo , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Animales , Astrocitos/metabolismo , Cerebelo/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismoRESUMEN
AIMS: Adenosine receptors and extracellular adenosine have been demonstrated to modulate vascular smooth muscle cell (VSMC) proliferation and neointima formation. Adenosine kinase (ADK) is a major enzyme regulating intracellular adenosine levels but is function in VSMC remains unclear. Here, we investigated the role of ADK in vascular injury-induced smooth muscle proliferation and delineated the mechanisms underlying its action. METHODS AND RESULTS: We found that ADK expression was higher in the neointima of injured vessels and in platelet-derived growth factor-treated VSMCs. Genetic and pharmacological inhibition of ADK was enough to attenuate arterial injury-induced neointima formation due to inhibition of VSMC proliferation. Mechanistically, using infinium methylation assays and bisulfite sequencing, we showed that ADK metabolized the intracellular adenosine and potentiated the transmethylation pathway, then induced the aberrant DNA hypermethylation. Pharmacological inhibition of aberrant DNA hypermethylation increased KLF4 expression and suppressed VSMC proliferation as well as the neointima formation. Importantly, in human femoral arteries, we observed increased ADK expression and DNA hypermethylation as well as decreased KLF4 expression in neointimal VSMCs of stenotic vessels suggesting that our findings in mice are relevant for human disease and may hold translational significance. CONCLUSION: Our study unravels a novel mechanism by which ADK promotes VSMC proliferation via inducing aberrant DNA hypermethylation, thereby down-regulating KLF4 expression and promoting neointima formation. These findings advance the possibility of targeting ADK as an epigenetic modulator to combat vascular injury.
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Adenosina Quinasa/metabolismo , Traumatismos de las Arterias Carótidas/enzimología , Proliferación Celular , Metilación de ADN , Epigénesis Genética , Músculo Liso Vascular/enzimología , Miocitos del Músculo Liso/enzimología , Neointima , Adenosina Quinasa/genética , Animales , Arterias Carótidas/enzimología , Arterias Carótidas/patología , Traumatismos de las Arterias Carótidas/genética , Traumatismos de las Arterias Carótidas/patología , Traumatismos de las Arterias Carótidas/prevención & control , Modelos Animales de Enfermedad , Humanos , Factor 4 Similar a Kruppel/genética , Factor 4 Similar a Kruppel/metabolismo , Ratones Noqueados , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/patología , Remodelación VascularRESUMEN
Adenosine kinase (ADK) deficiency is characterized by liver disease, dysmorphic features, epilepsy and developmental delay. This defect disrupts the adenosine/AMP futile cycle and interferes with the upstream methionine cycle. We report the clinical, histological and biochemical courses of three ADK children carrying two new mutations and presenting with neonatal cholestasis and neurological disorders. One of them died of liver failure whereas the other two recovered from their liver damage. As the phenotype was consistent with a mitochondrial disorder, we studied liver mitochondrial respiratory chain activities in two patients and revealed a combined defect of several complexes. In addition, we retrospectively analyzed methionine plasma concentration, a hallmark of ADK deficiency, in a cohort of children and showed that methionine level in patients with ADK deficiency was strongly increased compared with patients with other liver diseases. ADK deficiency is a cause of neonatal or early infantile liver disease that may mimic primary mitochondrial disorders. In this context, an elevation of methionine plasma levels over twice the upper limit should not be considered as a nonspecific finding. ADK deficiency induced-liver dysfunction is most often transient, but could be life-threatening.
Asunto(s)
Adenosina Quinasa/genética , Errores Innatos del Metabolismo de los Aminoácidos/genética , Discapacidades del Desarrollo/genética , Epilepsia/genética , Glicina N-Metiltransferasa/deficiencia , Adenosina/genética , Adenosina/metabolismo , Adenosina Quinasa/deficiencia , Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Errores Innatos del Metabolismo de los Aminoácidos/patología , Niño , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/patología , Epilepsia/complicaciones , Epilepsia/patología , Femenino , Predisposición Genética a la Enfermedad , Glicina N-Metiltransferasa/genética , Humanos , Lactante , Recién Nacido , Hepatopatías/complicaciones , Hepatopatías/genética , Hepatopatías/patología , Masculino , Estudios RetrospectivosRESUMEN
Genistein can be used as a dietary additive to control fat deposition in animals, while its mechanism is poorly understood. In this study, a total of 144 male broilers were randomly divided into 4 groups. Birds were fed standard diets supplemented with 0, 50, 100 or 150 mg of genistein/kg from 21 to 42 d of age. Results showed that genistein treatment decreased the relative weight of abdominal fat and triglyceride contents in broiler chickens. Genistein downregulated hepatic lipid droplets accumulation and upregulated the activity of lipoprotein lipase and hepatic lipase and the concentration of adiponectin. Furthermore, the liver X receptor α, sterol regulatory element-binding protein 1c (SREBP-1c), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) mRNA expressions were decreased, whereas adiponectin receptor 2, peroxisome proliferator-activated receptor α, adipose triglyceride lipase, and carnitine palmitoyl transferase-I (CPT-I) mRNA abundances were increased in the liver of broilers treated with genistein. In addition, genistein increased the NAD+ concentration and NAD+/NADH ratio in the liver. Genistein increased estrogen receptor ß (ERß), forkhead box O1, nicotinamide phosphoribosyl transferase, sirtuin1 (SIRT1), phospho (p)-adenosine 5'-monophosphate-activated protein kinase (AMPK), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α), p-ACC, and CPT-I protein levels, whereas the SREBP-1c and FAS levels were decreased. These data indicated that genistein might reduce fat accumulation in broiler chickens via activating the AMPK-SIRT1/PGC-1α signaling pathway. The activation of this signaling pathway might be achieved by its direct effect on improving the adiponectin secretion or its indirect effect on upregulation of ERß expression level through paracrine acting of adiponectin.
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Pollos , Genisteína , Metabolismo de los Lípidos , Redes y Vías Metabólicas , Transducción de Señal , Sirtuina 1 , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Adiponectina/metabolismo , Animales , Receptor beta de Estrógeno/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Genisteína/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Redes y Vías Metabólicas/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Sirtuina 1/metabolismoRESUMEN
OBJECTIVE: Inhibition of adenosine kinase (ADK), via augmenting endogenous adenosine levels exerts cardiovascular protection. We tested the hypothesis that ADK inhibition improves microvascular dilator and left ventricle (LV) contractile function under metabolic or hemodynamic stress. METHODS AND RESULTS: In Obese diabetic Zucker fatty/spontaneously hypertensive heart failure F1 hybrid rats, treatment with the selective ADK inhibitor, ABT-702 (1.5 mg/kg, intraperitoneal injections for 8-week) restored acetylcholine-, sodium nitroprusside-, and adenosine-induced dilations in isolated coronary arterioles, an effect that was accompanied by normalized end-diastolic pressure (in mm Hg, Lean: 3.4 ± 0.6, Obese: 17.6 ± 4.2, Obese + ABT: 6.6 ± 1.4) and LV relaxation constant, Tau (in ms, Lean: 6.9 ± 1.5, Obese: 13.9 ± 1.7, Obese + ABT: 6.0 ± 1.1). Mice with vascular endothelium selective ADK deletion (ADKVEC KO) exhibited an enhanced dilation to acetylcholine in isolated gracilis muscle (lgEC50 WT: -8.2 ± 0.1, ADKVEC KO: -8.8 ± 0.1, P < .05) and mesenteric arterioles (lgEC50 WT: -7.4 ± 0.2, ADKVEC KO: -8.1 ± 1.2, P < .05) when compared to wild-type (WT) mice, whereas relaxation of the femoral artery and aorta (lgEC50 WT: -7.03 ± 0.6, ADKVEC KO: -7.05 ± 0.8) was similar in the two groups. Wild-type mice progressively developed LV systolic and diastolic dysfunction when they underwent transverse aortic constriction surgery, whereas ADKVEC -KO mice displayed a lesser degree in decline of LV function. CONCLUSIONS: Our results indicate that ADK inhibition selectively enhances microvascular vasodilator function, whereby it improves LV perfusion and LV contractile function under metabolic and hemodynamic stress.
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Adenosina Quinasa/antagonistas & inhibidores , Microvasos/enzimología , Morfolinas/farmacología , Pirimidinas/farmacología , Vasodilatación/efectos de los fármacos , Disfunción Ventricular Izquierda/enzimología , Adenosina Quinasa/genética , Adenosina Quinasa/metabolismo , Animales , Diástole/efectos de los fármacos , Diástole/genética , Masculino , Ratones , Ratones Noqueados , Ratas , Ratas Zucker , Vasodilatación/genética , Disfunción Ventricular Izquierda/genéticaRESUMEN
The adenosine hypothesis of schizophrenia posits that reduced availability of the neuromodulator adenosine contributes to dysregulation of dopamine and glutamate transmission and the symptoms associated with schizophrenia. It has been proposed that increased expression of the enzyme adenosine kinase (ADK) may drive hypofunction of the adenosine system. While animal models of ADK overexpression support such a role for altered ADK, the expression of ADK in schizophrenia has yet to be examined. In this study, we assayed ADK gene and protein expression in frontocortical tissue from schizophrenia subjects. In the dorsolateral prefrontal cortex (DLPFC), ADK-long and -short splice variant expression was not significantly altered in schizophrenia compared to controls. There was also no significant difference in ADK splice variant expression in the frontal cortex of rats treated chronically with haloperidol-decanoate, in a study to identify the effect of antipsychotics on ADK gene expression. ADK protein expression was not significantly altered in the DLPFC or anterior cingulate cortex (ACC). There was no significant effect of antipsychotic medication on ADK protein expression in the DLPFC or ACC. Overall, our results suggest that increased ADK expression does not contribute to hypofunction of the adenosine system in schizophrenia and that alternative mechanisms are involved in dysregulation of this system in schizophrenia.
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Adenosina Quinasa/metabolismo , Adenosina/metabolismo , Antipsicóticos/farmacología , Expresión Génica , Giro del Cíngulo/metabolismo , Corteza Prefrontal/metabolismo , Esquizofrenia/metabolismo , Adenosina Quinasa/efectos de los fármacos , Adenosina Quinasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Animales , Femenino , Expresión Génica/efectos de los fármacos , Giro del Cíngulo/efectos de los fármacos , Giro del Cíngulo/enzimología , Células Hep G2 , Humanos , Masculino , Persona de Mediana Edad , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/enzimología , Ratas , Ratas Sprague-Dawley , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/enzimología , Bancos de TejidosRESUMEN
Psychotropic Psilocybe mushrooms biosynthesize their principal natural product psilocybin in five steps, among them a phosphotransfer and two methyltransfer reactions, which consume one equivalent of 5'-adenosine triphosphate (ATP) and two equivalents of S-adenosyl-l-methionine (SAM). This short but co-substrate-intensive pathway requires nucleoside cofactor salvage to maintain high psilocybin production rates. We characterized the adenosine kinase (AdoK) and S-adenosyl-l-homocysteine (SAH) hydrolase (SahH) of Psilocybe cubensis. Both enzymes are directly or indirectly involved in regenerating SAM. qRT-PCR expression analysis revealed an induced expression of the genes in the fungal primordia and carpophores. A one-pot in vitro reaction with the N-methyltransferase PsiM of the psilocybin pathway demonstrates a concerted action with SahH to facilitate biosynthesis by removal of accumulating SAH.
Asunto(s)
Adenosina Quinasa/metabolismo , Adenosina/metabolismo , Adenosilhomocisteinasa/metabolismo , Psilocybe/enzimología , Psilocibina/biosíntesis , S-Adenosilmetionina/metabolismo , Adenosina Quinasa/genética , Adenosilhomocisteinasa/genética , Perfilación de la Expresión Génica , Psilocybe/genéticaRESUMEN
Gestational diabetes mellitus (GDM) is a detrimental condition for human pregnancy associated with endothelial dysfunction and endothelial inflammation in the fetoplacental vasculature and leads to increased cardio-metabolic risk in the offspring. In the fetoplacental vasculature, GDM is associated with altered adenosine metabolism. Adenosine is an important vasoactive molecule and is an intermediary and final product of transmethylation reactions in the cell. Adenosine kinase is the major regulator of adenosine levels. Disruption of this enzyme is associated with alterations in methylation-dependent gene expression regulation mechanisms, which are associated with the fetal programming phenomenon. Here we propose that cellular and molecular alterations associated with GDM can dysregulate adenosine kinase leading to fetal programming in the fetoplacental vasculature. This can contribute to the cardio-metabolic long-term consequences observed in offspring after exposure to GDM.
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Adenosina Quinasa/metabolismo , Sistema Cardiovascular/metabolismo , Diabetes Gestacional/metabolismo , Desarrollo Fetal/fisiología , Placenta/metabolismo , Adenosina/metabolismo , Adenosina Quinasa/genética , Animales , Metilación de ADN , Diabetes Mellitus/metabolismo , Diabetes Gestacional/genética , Endotelio/metabolismo , Epigenómica , Femenino , Desarrollo Fetal/genética , Regulación de la Expresión Génica , Humanos , Inflamación , Ratones , EmbarazoRESUMEN
Adenosine kinase (ADK) is the first enzyme in the adenosine remediation pathway that catalyzes adenosine phosphorylation into adenosine monophosphate, thus regulating adenosine homeostasis in cells. To obtain new insights into ADK from Bombyx mori (BmADK), we obtained recombinant BmADK, and analyzed its activity, structure, and function. Gel-filtration showed BmADK was a monomer with molecular weight of approximately 38 kDa. Circular dichroism spectra indicated BmADK had 36.8% α-helix and 29.9% ß-strand structures, respectively. The structure of BmADK was stable in pH 5.0-11.0, and not affected under 30 °C. The melting temperature and the enthalpy and entropy changes in the thermal transition of BmADK were 46.51 ± 0.50 °C, 253.43 ± 0.20 KJ/mol, and 0.79 ± 0.01 KJ/(mol·K), respectively. Site-directed mutagenesis demonstrated G68, S201, E229, and D303 were key amino acids for BmADK structure and activity. In particular, S201A mutation significantly increased the α-helix content of BmADK and its activity. BmADK was located in the cytoplasm and highly expressed in the silk gland during the pre-pupal stage. RNA interference revealed the downregulation of BmADK decreased ATG-8, Caspase-9, Ec-R, E74A, and Br-C expression, indicating it was likely involved in 20E signaling, apoptosis, and autophagy to regulate silk gland degeneration and silkworm metamorphosis. Our study greatly expanded the knowledge on the activity, structure, and role of ADK.
Asunto(s)
Adenosina Quinasa/genética , Bombyx/genética , Proteínas de Insectos/genética , Larva/genética , Pupa/genética , Adenosina/química , Adenosina/metabolismo , Adenosina Quinasa/química , Adenosina Quinasa/metabolismo , Adenosina Monofosfato/química , Adenosina Monofosfato/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Bombyx/enzimología , Bombyx/crecimiento & desarrollo , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Regulación del Desarrollo de la Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Cinética , Larva/enzimología , Larva/crecimiento & desarrollo , Modelos Moleculares , Fosforilación , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Pupa/enzimología , Pupa/crecimiento & desarrollo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por SustratoRESUMEN
Insulin resistance-related disorders are associated with endothelial dysfunction. Accumulating evidence has suggested a role for adenosine signaling in the regulation of endothelial function. Here, we identified a crucial role of endothelial adenosine kinase (ADK) in the regulation of insulin resistance. Feeding mice with a high-fat diet (HFD) markedly enhanced the expression of endothelial Adk. Ablation of endothelial Adk in HFD-fed mice improved glucose tolerance and insulin sensitivity and decreased hepatic steatosis, adipose inflammation and adiposity, which were associated with improved arteriole vasodilation, decreased inflammation and increased adipose angiogenesis. Mechanistically, ADK inhibition or knockdown in human umbilical vein endothelial cells (HUVECs) elevated intracellular adenosine level and increased endothelial nitric oxide synthase (NOS3) activity, resulting in an increase in nitric oxide (NO) production. Antagonism of adenosine receptor A2b abolished ADK-knockdown-enhanced NOS3 expression in HUVECs. Additionally, increased phosphorylation of NOS3 in ADK-knockdown HUVECs was regulated by an adenosine receptor-independent mechanism. These data suggest that Adk-deficiency-elevated intracellular adenosine in endothelial cells ameliorates diet-induced insulin resistance and metabolic disorders, and this is associated with an enhancement of NO production caused by increased NOS3 expression and activation. Therefore, ADK is a potential target for the prevention and treatment of metabolic disorders associated with insulin resistance.