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1.
Cells ; 9(9)2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32854430

RESUMO

An outbreak of the novel coronavirus (CoV) SARS-CoV-2, the causative agent of COVID-19 respiratory disease, infected millions of people since the end of 2019, led to high-level morbidity and mortality and caused worldwide social and economic disruption. There are currently no antiviral drugs available with proven efficacy or vaccines for its prevention. An understanding of the underlying cellular mechanisms involved in virus replication is essential for repurposing the existing drugs and/or the discovery of new ones. Endocytosis is the important mechanism of entry of CoVs into host cells. Endosomal maturation followed by the fusion with lysosomes are crucial events in endocytosis. Late endosomes and lysosomes are characterized by their acidic pH, which is generated by a proton transporter V-ATPase and required for virus entry via endocytic pathway. The cytoplasmic cAMP pool produced by soluble adenylyl cyclase (sAC) promotes V-ATPase recruitment to endosomes/lysosomes and thus their acidification. In this review, we discuss targeting the sAC-specific cAMP pool as a potential strategy to impair the endocytic entry of the SARS-CoV-2 into the host cell. Furthermore, we consider the potential impact of sAC inhibition on CoV-induced disease via modulation of autophagy and apoptosis.


Assuntos
Inibidores de Adenilil Ciclases/uso terapêutico , Adenilil Ciclases/metabolismo , Betacoronavirus/fisiologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/prevenção & controle , AMP Cíclico/antagonistas & inibidores , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/prevenção & controle , Antivirais/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Endocitose/efeitos dos fármacos , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Pneumonia Viral/metabolismo , Pneumonia Viral/virologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
2.
PLoS One ; 15(8): e0231806, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817622

RESUMO

The cAMP-dependent protein kinase (PKA) signaling pathway is the primary means by which the heart regulates moment-to-moment changes in contractility and metabolism. We have previously found that PKA signaling is dysfunctional in the diabetic heart, yet the underlying mechanisms are not fully understood. The objective of this study was to determine if decreased insulin signaling contributes to a dysfunctional PKA response. To do so, we isolated adult cardiomyocytes (ACMs) from wild type and Akita type 1 diabetic mice. ACMs were cultured in the presence or absence of insulin and PKA signaling was visualized by immunofluorescence microscopy using an antibody that recognizes proteins specifically phosphorylated by PKA. We found significant decreases in proteins phosphorylated by PKA in wild type ACMs cultured in the absence of insulin. PKA substrate phosphorylation was decreased in Akita ACMs, as compared to wild type, and unresponsive to the effects of insulin. The decrease in PKA signaling was observed regardless of whether the kinase was stimulated with a beta-agonist, a cell-permeable cAMP analog, or with phosphodiesterase inhibitors. PKA content was unaffected, suggesting that the decrease in PKA signaling may be occurring by the loss of specific PKA substrates. Phospho-specific antibodies were used to discern which potential substrates may be sensitive to the loss of insulin. Contractile proteins were phosphorylated similarly in wild type and Akita ACMs regardless of insulin. However, phosphorylation of the glycolytic regulator, PFK-2, was significantly decreased in an insulin-dependent manner in wild type ACMs and in an insulin-independent manner in Akita ACMs. These results demonstrate a defect in PKA activation in the diabetic heart, mediated in part by deficient insulin signaling, that results in an abnormal activation of a primary metabolic regulator.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diabetes Mellitus/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Insulina/metabolismo , Insulina/farmacologia , Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/fisiologia , Inibidores de Fosfodiesterase/farmacologia , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos
3.
PLoS One ; 15(7): e0236892, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735622

RESUMO

There is a significant unmet need for a safe and effective therapy for the treatment of children with congenital hyperinsulinism. We hypothesized that amplification of the glucagon signaling pathway could ameliorate hyperinsulinism associated hypoglycemia. In order to test this we evaluated the effects of loss of Prkar1a, a negative regulator of Protein Kinase A in the context of hyperinsulinemic conditions. With reduction of Prkar1a expression, we observed a significant upregulation of hepatic gluconeogenic genes. In wild type mice receiving a continuous infusion of insulin by mini-osmotic pump, we observed a 2-fold increase in the level of circulating ketones and a more than 40-fold increase in Kiss1 expression with reduction of Prkar1a. Loss of Prkar1a in the Sur1-/- mouse model of KATP hyperinsulinism significantly attenuated fasting induced hypoglycemia, decreased the insulin/glucose ratio, and also increased the hepatic expression of Kiss1 by more than 10-fold. Together these data demonstrate that amplification of the hepatic glucagon signaling pathway is able to rescue hypoglycemia caused by hyperinsulinism.


Assuntos
Hiperinsulinismo Congênito/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Kisspeptinas/genética , Receptores Sulfonilureia/genética , Animais , Hiperinsulinismo Congênito/genética , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Gluconeogênese/genética , Glucose/metabolismo , Hipoglicemia/metabolismo , Insulina/metabolismo , Cetonas/metabolismo , Kisspeptinas/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Knockout , Transdução de Sinais
4.
Mol Pharmacol ; 98(2): 143-155, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32616523

RESUMO

The two-pore domain potassium channel (K2P-channel) THIK-1 has several predicted protein kinase A (PKA) phosphorylation sites. In trying to elucidate whether THIK-1 is regulated via PKA, we expressed THIK-1 channels in a mammalian cell line (CHO cells) and used the phosphodiesterase inhibitor 3-isobutyl-1-methyl-xanthine (IBMX) as a pharmacological tool to induce activation of PKA. Using the whole-cell patch-clamp recording, we found that THIK-1 currents were inhibited by application of IBMX with an IC50 of 120 µM. Surprisingly, intracellular application of IBMX or of the second messenger cAMP via the patch pipette had no effect on THIK-1 currents. In contrast, extracellular application of IBMX produced a rapid and reversible inhibition of THIK-1. In patch-clamp experiments with outside-out patches, THIK-1 currents were also inhibited by extracellular application of IBMX. Expression of THIK-1 channels in Xenopus oocytes was used to compare wild-type channels with mutated channels. Mutation of the putative PKA phosphorylation sites did not change the inhibitory effect of IBMX on THIK-1 currents. Mutational analysis of all residues of the (extracellular) helical cap of THIK-1 showed that mutation of the arginine residue at position 92, which is in the linker between cap helix 2 and pore helix 1, markedly reduced the inhibitory effect of IBMX. This flexible linker region, which is unique for each K2P-channel subtype, may be a possible target of channel-specific blockers. SIGNIFICANCE STATEMENT: The potassium channel THIK-1 is strongly expressed in the central nervous system. We studied the effect of 3-isobutyl-1-methyl-xanthine (IBMX) on THIK-1 currents. IBMX inhibits breakdown of cAMP and thus activates protein kinase A (PKA). Surprisingly, THIK-1 current was inhibited when IBMX was applied from the extracellular side of the membrane, but not from the intracellular side. Our results suggest that IBMX binds directly to the channel and that the inhibition of THIK-1 current was not related to activation of PKA.


Assuntos
1-Metil-3-Isobutilxantina/farmacologia , Canais de Potássio de Domínios Poros em Tandem/química , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Animais , Arginina/genética , Sítios de Ligação/efeitos dos fármacos , Células CHO , Cricetulus , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Mutação , Técnicas de Patch-Clamp , Canais de Potássio de Domínios Poros em Tandem/antagonistas & inibidores , Canais de Potássio de Domínios Poros em Tandem/genética , Ratos , Xenopus
5.
Proc Natl Acad Sci U S A ; 117(25): 14220-14230, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513741

RESUMO

Because raising cAMP enhances 26S proteasome activity and the degradation of cell proteins, including the selective breakdown of misfolded proteins, we investigated whether agents that raise cGMP may also regulate protein degradation. Treating various cell lines with inhibitors of phosphodiesterase 5 or stimulators of soluble guanylyl cyclase rapidly enhanced multiple proteasome activities and cellular levels of ubiquitinated proteins by activating protein kinase G (PKG). PKG stimulated purified 26S proteasomes by phosphorylating a different 26S component than is modified by protein kinase A. In cells and cell extracts, raising cGMP also enhanced within minutes ubiquitin conjugation to cell proteins. Raising cGMP, like raising cAMP, stimulated the degradation of short-lived cell proteins, but unlike cAMP, also markedly increased proteasomal degradation of long-lived proteins (the bulk of cell proteins) without affecting lysosomal proteolysis. We also tested if raising cGMP, like cAMP, can promote the degradation of mutant proteins that cause neurodegenerative diseases. Treating zebrafish models of tauopathies or Huntington's disease with a PDE5 inhibitor reduced the levels of the mutant huntingtin and tau proteins, cell death, and the resulting morphological abnormalities. Thus, PKG rapidly activates cytosolic proteasomes, protein ubiquitination, and overall protein degradation, and agents that raise cGMP may help combat the progression of neurodegenerative diseases.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Doenças Neurodegenerativas/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Animais , Animais Geneticamente Modificados , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Humanos , Fosforilação , Tauopatias , Ubiquitina/metabolismo , Proteínas Ubiquitinadas/metabolismo , Ubiquitinação , Peixe-Zebra , Proteínas tau/metabolismo
6.
Prostate ; 80(11): 885-894, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32483877

RESUMO

BACKGROUND: Eradication of persistent androgen receptor (AR) activity in castration-resistant prostate cancer may be a promising strategy to overcome castration resistance. We aimed to identify novel compounds that inhibit AR activity and could be potential therapeutic agents for prostate cancer. METHODS: A high-throughput screening system involving cell lines stably expressing AR protein and AR-responsive luciferase was employed for the 1260 compound library. Molecular and antitumor effects on candidate pathways that interacted with AR signaling were examined in prostate cancer cells expressing AR. RESULTS: The high-throughput screening identified various potential compounds that interfered with AR signaling through known and novel pathways. Among them, a 5-hydroxytryptamine 5A (5-HT5A) receptor antagonist suppressed AR activity through protein kinase A signaling, which was confirmed by 5-HT5A receptor knockdown. Consistently, 5-HT5A receptor inhibitors showed cytotoxic effects toward prostate cancer cells. CONCLUSIONS: Taken together, this study identifies 5-HT5A receptor as a promising therapeutic target for prostate cancer via its interaction with AR signaling.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Androgênios/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Linhagem Celular Tumoral , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Ensaios de Triagem em Larga Escala/métodos , Humanos , Masculino , Células PC-3 , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo
7.
Life Sci ; 256: 117922, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32522569

RESUMO

To test the hypothesis of STC-1 participation in maintenance of glucose homeostasis in fed and fasting (48 h) rats, we investigated that this hormone may be implicated in the regulation of renal gluconeogenesis pathway from lactate and lactate oxidation in renal cortex and medulla. Our results demonstrate the hSTC-1 role on lactate metabolism in the renal cortex and medulla from fed and fasting rats. hSTC-1 increased the gluconeogenesis activity in fed state in renal cortex, and this increase was induced by raise in Pck1 gene expression. In fasting animals hSTC-1 increase the renal medulla gluconeogenesis activity, but Pck1 gene expression was not alter. The stimulatory effect of hSTC-1 on 14C-lactate oxidation occurred only in the renal cortex from fed rats. These findings show the hSTC-1 contribution to lactate homeostasis and supplies glucose to other tissues. This response may represent a strategy of action of STC-1 in response to fasting stress as postulated by different authors. On the other hand, hSTC-1 acts downstream of adenylcyclase pathway, decreasing the gluconeogenesis activity induced by cAMP intracellular increase or stimulating the phosphodiesterase activity in the renal cortex. However, no hSTC-1 effect on 14C-lactate oxidation was found after increase in the intracellular cAMP. The findings also revealed that the renal cortex and medulla respond differently to hSTC-1, possibly due to the higher level of STC-1 gene expression in inner renal medulla than in renal cortex.


Assuntos
Gluconeogênese/efeitos dos fármacos , Glicoproteínas/metabolismo , Hormônios/metabolismo , Rim/metabolismo , Lactatos/metabolismo , Proteínas Recombinantes/metabolismo , Adenilil Ciclases/metabolismo , Animais , Dióxido de Carbono/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação da Expressão Gênica , Glucose/metabolismo , Glicoproteínas/genética , Hormônios/genética , Humanos , Córtex Renal/metabolismo , Medula Renal/metabolismo , Masculino , Oxirredução , Diester Fosfórico Hidrolases/metabolismo , Ratos , Ratos Wistar , Proteínas Recombinantes/genética , Transdução de Sinais
8.
Mol Immunol ; 124: 142-152, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32563859

RESUMO

Long noncoding RNAs (lncRNAs) play an indispensable role in the process of M1 macrophage via regulating the development of macrophages and their responses to bacterial pathogens and viral infections. However, there are few studies on the lncRNA-mediated functions and regulatory mechanisms of M2 macrophage polarization. In this study, we found a number of differentially expressed lncRNAs between human monocyte derived M0 and M2 macrophages according to array analysis and quantitative polymerase chain reaction (qPCR) validation. The lncRNA RP11-389C8.2 (we named lnc-M2 in this study) was observed to be highly expressed in M2 macrophages. In Situ Localization and Quantification Analysis showed that lnc-M2 was expressed in the nucleus and cytosolic compartments of M2 macrophages. Notably, lnc-M2 knockdown enhanced the phagocytic ability of M2 macrophages. Ulteriorly, the results of RNA-Protein interaction experiments indicated that protein kinase A (PKA) was a lnc-M2 associated RNA-binding protein (RBP). Western blot showed that phosphorylated cAMP response element binding protein (p-CREB), a well-known key downstream transcription factor of PKA, was lowly phosphorylated in lnc-M2-silencing M2 macrophages. Furthermore, we found that transcriptional factor Signal Transducer And Activator Of Transcription 3 (STAT3) promoted lnc-M2 transcription along with the up-regulation of epigenetic histone modification markers at the lnc-M2 promoter locus, indicating that STAT3 activated lnc-M2 and eventually facilitated the process of M2 macrophage differentiation via the PKA/CREB pathway. Collectively, our date provide evidence that the transcription factor STAT3 can promote the transcription of lnc-M2 and facilitated the process of M2 macrophage differentiation via the PKA/CREB pathway. This study highlights a novel mechanism underlying the M2 macrophage differentiation.


Assuntos
Regulação da Expressão Gênica/imunologia , Ativação de Macrófagos/genética , Macrófagos/imunologia , RNA Longo não Codificante/genética , Diferenciação Celular/genética , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Macrófagos/metabolismo , RNA Longo não Codificante/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/imunologia
9.
Scand J Immunol ; 92(3): e12922, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32592188

RESUMO

Lipopolysaccharide (LPS)-responsive beige-like anchor (LRBA) protein was initially described as a monogenetic cause for common variable immune deficiency, a syndrome characterized by low levels of B cells, defects in memory B cell differentiation and hypogammaglobulinaemia. LRBA was identified as an LPS up-regulated gene in B cells, macrophages and T cells. LRBA weighs 320 kDa and has 2863 amino acids. Its sequence contains multiple domains, suggesting that LRBA can act as a scaffolding protein. It contains two putative binding sites for cAMP-dependent kinase (PKA) regulatory subunits, suggesting this protein can act as A-kinase anchor protein (AKAP); however, physical interactions involving LRBA and PKA have not been demonstrated to date, and functional roles for such interactions are unexplored. In this work, we investigated physical interactions involving LRBA with regulatory subunits of PKA in human B cell lines and primary human B cells. PKA is a holoenzyme composed of two regulatory subunits, which can be RIα, RIß, RIIα or RIIß, and two catalytic subunits, Cα or Cß. We co-immunoprecipitated LRBA using Ramos B cell lymphoma cells and observed that LRBA interacts with RIIß. Interestingly, St-Ht31, an inhibitory peptide that disrupts AKAP interactions with regulatory subunits, reduced the amount of interacting protein. Furthermore, in primary human B cells, LRBA was induced after CD40L and IL-4 stimulation, and under such activation, we found that LRBA interacts with RIIα and RIIß, suggesting that LRBA acts as an AKAP and binds RII subunits. Interestingly, we also identified that LRBA interacts with activation-induced cytidine deaminase in primary B cells, suggesting that it is involved in B cell function.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Ligante de CD40/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/química , Humanos , Interleucina-4/metabolismo , Ativação Linfocitária/imunologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico
10.
Arterioscler Thromb Vasc Biol ; 40(6): e166-e179, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32349534

RESUMO

OBJECTIVE: Recent studies suggest that the P2Y12 (P2Y purinoceptor 12) receptor of vascular smooth muscle cells in atherosclerotic plaques aggravates atherosclerosis, and P2Y12 receptor inhibitors such as CDL (clopidogrel) may effectively treat atherosclerosis. It is imperative to identify an effective biomarker for reflecting the P2Y12 receptor expression on vascular smooth muscle cells in plaques. Approach and Results: We found that there was a positive correlation between the level of circulating sLRP1 (soluble low-density lipoprotein receptor-related protein 1) and the number of LRP1+ α-SMA+ (α-smooth muscle actin), P2Y12+, or P2Y12+ LRP1+ cells in plaques from apoE-/- mice fed a high-fat diet. Furthermore, activation of the P2Y12 receptor increased the expression and shedding of LRP1 in vascular smooth muscle cells by inhibiting cAMP (3'-5'-cyclic adenosine monophosphate)/PKA (protein kinase A)/SREBP-2 (sterol regulatory element binding transcription factor 2). Conversely, genetic knockdown or pharmacological inhibition of the P2Y12 receptor had the opposite effects. Additionally, CDL decreased the number of lesional LRP1+ α-SMA+ cells and the levels of circulating sLRP1 by activating cAMP/PKA/SREBP-2 in apoE-/- mice fed a high-fat diet. CONCLUSIONS: Our study suggests that sLRP1 may be a biomarker that reflects the P2Y12 receptor level in plaques and has the potential to be an indicator for administering P2Y12 receptor inhibitors for patients with atherosclerosis.


Assuntos
Biomarcadores/análise , Expressão Gênica , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/análise , Placa Aterosclerótica/metabolismo , Receptores Purinérgicos P2Y12/genética , Actinas/análise , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Apolipoproteínas E/fisiologia , Clopidogrel/farmacologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dieta Hiperlipídica , Técnicas de Silenciamento de Genes , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/química , Músculo Liso Vascular/metabolismo , Placa Aterosclerótica/química , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Receptores Purinérgicos P2Y12/fisiologia , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
11.
PLoS One ; 15(5): e0233863, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32470053

RESUMO

Adaptive regulation of epithelial transporters to nutrient intake is essential to decrease energy costs of their synthesis and maintenance, however such regulation is understudied. Previously we demonstrated that the transport function of the basolateral amino acid uniporter LAT4 (Slc43a2) is increased by dephosphorylation of serine 274 (S274) and nearly abolished by dephosphorylation of serine 297 (S297) when expressed in Xenopus oocytes. Phosphorylation changes in the jejunum of food-entrained mice suggested an increase in LAT4 transport function during food expectation. Thus, we investigated further how phosphorylation, expression and localization of mouse intestinal LAT4 respond to food-entrained diurnal rhythm and dietary protein content. In mice entrained with 18% protein diet, LAT4 mRNA was not submitted to diurnal regulation, unlike mRNAs of luminal symporters and antiporters. Only in duodenum, LAT4 protein expression increased during food intake. Concurrently, S274 phosphorylation was decreased in all three small intestinal segments, whereas S297 phosphorylation was increased only in jejunum. Interestingly, during food intake, S274 phosphorylation was nearly absent in ileum and accompanied by strong phosphorylation of mTORC1 target S6. Entraining mice with 8% protein diet provoked a shift in jejunal LAT4 localization from the cell surface to intracellular stores and increased S274 phosphorylation in both jejunum and ileum during food anticipation, suggesting decreased transport function. In contrast, 40% dietary protein content led to increased LAT4 expression in jejunum and its internalization in ileum. Ex vivo treatments of isolated intestinal villi fraction demonstrated that S274 phosphorylation was stimulated by protein kinase A. Rapamycin-sensitive insulin treatment and amino acids increased S297 phosphorylation, suggesting that the response to food intake might be regulated via the insulin-mTORC1 pathway. Ghrelin, an oscillating orexigenic hormone, did not affect phosphorylation of intestinal LAT4. Overall, we show that phosphorylation, expression and localization of intestinal mouse LAT4 responds to diurnal and dietary stimuli in location-specific manner.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Ritmo Circadiano , Proteínas na Dieta/farmacologia , Alimentos , Intestinos/fisiologia , Aminoácidos/metabolismo , Animais , Antiporters/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Grelina/administração & dosagem , Grelina/farmacologia , Insulina/metabolismo , Intestino Delgado/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Endogâmicos C57BL , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Frações Subcelulares/metabolismo , Simportadores/metabolismo , Serina-Treonina Quinases TOR/metabolismo
12.
Zhongguo Zhen Jiu ; 40(4): 397-404, 2020 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-32275369

RESUMO

OBJECTIVE: To observe the direct intervention effects of electroacupuncture (EA) and non-steroid anti-inflammatory drugs (NSAIDs) on pain memory, and to explore their effects on cAMP/PKA/cAMP pathway in anterior cingulate gyrus (ACC). METHODS: Fifty clean healthy male SD rats were randomly divided into a control group, a model group, an indomethacin group, an EA group and a sham EA group, 10 rats in each group. Except the control group, the pain memory model was established in the remaining four groups by twice injection of carrageenan at foot; 0.1 mL of 2%λ-carrageenan was subcutaneously injected at the left foot of rats; 14 days later, when the pain threshold of rats of each group returned to the basic level, the second injection was performed with the same procedure. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36) for 30 min; the rats in the indomethacin group was treated with indomethacin intragastric administration with the dose of 3 mg/kg; the rats in the sham EA group was treated with EA without electricity at the point 0.3 mm forward "Zusanli" (ST 36) with the depth of 2 mm for 30 min; the rats in the control group was not given any invention. All the above interventions were performed 5 h, 1 d, 2 d and 3 d after the second injection of 2% λ-carrageenan. The left-side paw withdrawal thresholds (PWT) were observed before the first injection, 4 h, 3 d, 5 d after the first injection, before the second injection and 4 h, 1 d, 2 d, 3 d after the second injection. Three days after the second injection, the number of positive cells of cAMP, p-PKA, p-CREB and the number of positive cells of protein co-expression in the right ACC brain area were detected by immunofluorescence, and the relative protein expression of p-PKA and p-CREB were detected by Western blot. RESULTS: Compared with the control group, the PWTs in the model group decreased significantly 4 h, 3 d and 5 d after the first injection and 1 d, 2 d and 3 d after the second injection (P<0.05); compared with the control group, the positive expression of cAMP, p-PKA and p-CREB in the right ACC brain area in the model group increased significantly (P<0.05), and the number of positive cells of the co-expression of cAMP/p-PKA and p-PKA/p-CREB also increased significantly (P<0.05). Compared with the model group, indomethacin group and sham EA group, the PWTs in the EA group were increased significantly 1 d, 2 d and 3 d after the second injection (P<0.05); compared with the model group, indomethacin group and sham EA group, the positive expression of p-PKA and p-CREB in the right ACC brain area in the EA group decreased significantly (P<0.05), and the number of positive cells of co-expression of cAMP/p-PKA and p-PKA/p-CREB was decreased significantly (P<0.05). Compared with the model group and sham EA group, the positive expression of cAMP in the right ACC brain area was decreased in the EA group (P<0.05). CONCLUSION: EA have a direct intervention effect on pain memory, which have significant advantage over NSAIDs in the treatment of chronic pain. The advantage effect of EA on pain memory may be related to the inhibition of cAMP/PKA/CREB pathway in ACC area.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Eletroacupuntura , Giro do Cíngulo/metabolismo , Limiar da Dor , Transdução de Sinais , Animais , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
13.
Anesthesiology ; 133(1): 165-184, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32349075

RESUMO

BACKGROUND: Brain-derived estrogen is implicated in pain-related aversion; however, which estrogen receptors mediate this effect remains unclear. This study hypothesized that the different estrogen receptors in the rostral anterior cingulate cortex play distinct roles in pain-related aversion. METHODS: Formalin-induced conditioned place avoidance and place escape/avoidance paradigms were used to evaluate pain-related aversion in rodents. Immunohistochemistry and Western blotting were used to detect estrogen receptor expression. Patch-clamp recordings were used to examine N-methyl-D-aspartate-mediated excitatory postsynaptic currents in rostral anterior cingulate cortex slices. RESULTS: The administration of the estrogen receptor-ß antagonist 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP) or the G protein-coupled estrogen receptor-1 antagonist (3aS*,4R*,9bR*)-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15) but not the estrogen receptor-α antagonist 1,3-bis (4-hydroxyphenyl)-4-methyl-5-[4-(2-piperidinylethoxy) phenol]-1H-pyrazole dihydrochloride (MPP) into the rostral anterior cingulate cortex blocked pain-related aversion in rats (avoidance score, mean ± SD: 1,3-bis [4-hydroxyphenyl]-4-methyl-5-(4-[2-piperidinylethoxy] phenol)-1H-pyrazole dihydrochloride (MPP): 47.0 ± 18.9%, 4-(2-phenyl-5,7-bis [trifluoromethyl] pyrazolo [1,5-a] pyrimidin-3-yl) phenol (PHTPP): -7.4 ± 20.6%, and [3aS*,4R*,9bR*]-4-[6-bromo-1,3-benzodioxol-5-yl]-3a,4,5,9b-3H-cyclopenta [c] quinolone (G15): -4.6 ± 17.0% vs. vehicle: 46.5 ± 12.2%; n = 7 to 9; P < 0.0001). Consistently, estrogen receptor-ß knockdown but not estrogen receptor-α knockdown by short-hairpin RNA also inhibited pain-related aversion in mice (avoidance score, mean ± SD: estrogen receptor-α-short-hairpin RNA: 26.0 ± 7.1% and estrogen receptor-ß-short-hairpin RNA: 6.3 ± 13.4% vs. control short-hairpin RNA: 29.1 ± 9.1%; n = 7 to 10; P < 0.0001). Furthermore, the direct administration of the estrogen receptor-ß agonist 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN) or the G protein-coupled estrogen receptor-1 agonist (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1) into the rostral anterior cingulate cortex resulted in conditioned place avoidance (avoidance score, mean ± SD: 2,3-bis (4-hydroxyphenyl)-propionitrile (DPN): 35.3 ± 9.5% and (±)-1-([3aR*,4S*,9bS*]-4-(6-bromo-1,3-benzodioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta [c]quinolin-8-yl)-ethanone (G1): 43.5 ± 22.8% vs. vehicle: 0.3 ± 14.9%; n = 8; P < 0.0001) but did not affect mechanical or thermal sensitivity. The activation of the estrogen receptor-ß/protein kinase A or G protein-coupled estrogen receptor-1/protein kinase B pathway elicited the long-term potentiation of N-methyl-D-aspartate-mediated excitatory postsynaptic currents. CONCLUSIONS: These findings indicate that estrogen receptor-ß and G protein-coupled estrogen receptor-1 but not estrogen receptor-α in the rostral anterior cingulate cortex contribute to pain-related aversion by modulating N-methyl-D-aspartate receptor-mediated excitatory synaptic transmission.


Assuntos
Giro do Cíngulo/fisiopatologia , Dor/fisiopatologia , Dor/psicologia , Receptores Estrogênicos , Animais , Aprendizagem da Esquiva , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/genética , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Antagonistas de Estrogênios/farmacologia , Receptor beta de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/genética , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Patch-Clamp , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Receptores Estrogênicos/efeitos dos fármacos , Receptores Estrogênicos/genética
14.
Nucleic Acids Res ; 48(14): 7864-7882, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32324228

RESUMO

It has been recently shown that many proteins are lacking from reference databases used in mass spectrometry analysis, due to their translation templated on alternative open reading frames. This questions our current understanding of gene annotation and drastically expands the theoretical proteome complexity. The functions of these alternative proteins (AltProts) still remain largely unknown. We have developed a large-scale and unsupervised approach based on cross-linking mass spectrometry (XL-MS) followed by shotgun proteomics to gather information on the functional role of AltProts by mapping them back into known signalling pathways through the identification of their reference protein (RefProt) interactors. We have identified and profiled AltProts in a cancer cell reprogramming system: NCH82 human glioma cells after 0, 16, 24 and 48 h Forskolin stimulation. Forskolin is a protein kinase A activator inducing cell differentiation and epithelial-mesenchymal transition. Our data show that AltMAP2, AltTRNAU1AP and AltEPHA5 interactions with tropomyosin 4 are downregulated under Forskolin treatment. In a wider perspective, Gene Ontology and pathway enrichment analysis (STRING) revealed that RefProts associated with AltProts are enriched in cellular mobility and transfer RNA regulation. This study strongly suggests novel roles of AltProts in multiple essential cellular functions and supports the importance of considering them in future biological studies.


Assuntos
Reprogramação Celular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Mapeamento de Interação de Proteínas , Linhagem Celular Tumoral , Reprogramação Celular/efeitos dos fármacos , Colforsina/farmacologia , Ativação Enzimática , Humanos , Espectrometria de Massas , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Proteômica , Proteínas de Ligação a RNA/metabolismo , Receptor EphA5/metabolismo , Transdução de Sinais , Tropomiosina/metabolismo
15.
J Neurosci ; 40(21): 4219-4229, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32303647

RESUMO

In Drosophila, the mushroom bodies (MB) constitute the central brain structure for olfactory associative memory. As in mammals, the cAMP/PKA pathway plays a key role in memory formation. In the MB, Rutabaga (Rut) adenylate cyclase acts as a coincidence detector during associative conditioning to integrate calcium influx resulting from acetylcholine stimulation and G-protein activation resulting from dopaminergic stimulation. Amnesiac encodes a secreted neuropeptide required in the MB for two phases of aversive olfactory memory. Previous sequence analysis has revealed strong homology with the mammalian pituitary adenylate cyclase-activating peptide (PACAP). Here, we examined whether amnesiac is involved in cAMP/PKA dynamics in response to dopamine and acetylcholine co-stimulation in living flies. Experiments were conducted with both sexes, or with either sex. Our data show that amnesiac is necessary for the PKA activation process that results from coincidence detection in the MB. Since PACAP peptide is cleaved by the human membrane neprilysin hNEP, we searched for an interaction between Amnesiac and Neprilysin 1 (Nep1), a fly neprilysin involved in memory. We show that when Nep1 expression is acutely knocked down in adult MB, memory deficits displayed by amn hypomorphic mutants are rescued. Consistently, Nep1 inhibition also restores normal PKA activation in amn mutant flies. Taken together, the results suggest that Nep1 targets Amnesiac degradation to terminate its signaling function. Our work thus highlights a key role for Amnesiac in establishing within the MB the PKA dynamics that sustain middle-term memory (MTM) formation, a function modulated by Nep1.SIGNIFICANCE STATEMENT The Drosophila amnesiac gene encodes a secreted neuropeptide whose expression is required for specific memory phases in the mushroom bodies (MB), the olfactory memory center. Here, we show that Amnesiac is required for PKA activation resulting from coincidence detection, a mechanism by which the MB integrate two spatially distinct stimuli to encode associative memory. Furthermore, our results uncover a functional relationship between Amnesiac and Neprilysin 1 (Nep1), a membrane peptidase involved in memory and expressed in the MB. These results suggest that Nep1 modulates Amnesiac levels. We propose that on conditioning, Amnesiac release from the MB allows, via an autocrine process, the sustaining of PKA activation-mediating memory, which subsequently is inactivated by Nep1 degradation.


Assuntos
Aprendizagem da Esquiva/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas de Drosophila/genética , Memória/fisiologia , Corpos Pedunculados/metabolismo , Neprilisina/metabolismo , Neuropeptídeos/genética , Animais , Animais Geneticamente Modificados , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Neuropeptídeos/metabolismo , Olfato/fisiologia
16.
Int J Mol Sci ; 21(7)2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32218156

RESUMO

This study examined the biological activities of copaiba essential oil via measurement of its effects on signaling pathways in the SH-SY5Y neuronal cell line. Nanofluidic proteomic technologies were deployed to measure the phosphorylation of biomarker proteins within the signaling cascades. Interestingly, copaiba essential oil upregulated the pI3K/Akt/mTOR, MAPK, and JAK/STAT signaling pathways in neuronal cells. The effects of copaiba essential oil peaked at 30 min post-treatment, with a half-maximal effective concentration (EC50) of approximately 80 ng/mL. Treatment with cannabinoid receptor 2 (CB2) agonist AM1241 or the inverse agonist BML190 abrogated the regulatory effects of copaiba essential oil on the pI3K/Akt/mTOR signaling pathway. Surprisingly, copaiba essential oil also activated the apoptosis signaling pathway and reduced the viability of SH-SY5Y cells with an EC50 of approximately 400 ng/mL. Furthermore, ß-caryophyllene, a principal constituent of copaiba essential oil, downregulated the pI3K/Akt/mTOR signaling pathway. Taken together, the findings indicated that copaiba essential oil upregulated signaling pathways associated with cell metabolism, growth, immunity, and apoptosis. The biological activities of copaiba essential oil were determined to be fast acting, CB2 mediated, and dependent on multiple chemical constituents of the oil. Nanofluidic proteomics provided a powerful means to assess the biological activities of copaiba essential oil.


Assuntos
Fabaceae/química , Neuroblastoma/metabolismo , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Neuroblastoma/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo
17.
PLoS One ; 15(3): e0230246, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32160258

RESUMO

Cells respond to changes in environmental conditions by activating signal transduction pathways and gene expression programs. Here we present a dataset to explore the relationship between environmental stresses, kinases, and global gene expression in yeast. We subjected 28 drug-sensitive kinase mutants to 10 environmental conditions in the presence of inhibitor and performed mRNA deep sequencing. With these data, we reconstructed canonical stress pathways and identified examples of crosstalk among pathways. The data also implicated numerous kinases in novel environment-specific roles. However, rather than regulating dedicated sets of target genes, individual kinases tuned the magnitude of induction of the environmental stress response (ESR)-a gene expression signature shared across the set of perturbations-in environment-specific ways. This suggests that the ESR integrates inputs from multiple sensory kinases to modulate gene expression and growth control. As an example, we provide experimental evidence that the high osmolarity glycerol pathway is an upstream negative regulator of protein kinase A, a known inhibitor of the ESR. These results elaborate the central axis of cellular stress response signaling.


Assuntos
Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulação Fúngica da Expressão Gênica/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfotransferases/genética , Fosfotransferases/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo
18.
Biochem Soc Trans ; 48(1): 39-49, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32065210

RESUMO

Cardiac excitation-contraction coupling is initiated with the influx of Ca2+ ions across the plasma membrane through voltage-gated L-type calcium channels. This process is tightly regulated by modulation of the channel open probability and channel localization. Protein kinase A (PKA) is found in close association with the channel and is one of the main regulators of its function. Whether this kinase is modulating the channel open probability by phosphorylation of key residues or via alternative mechanisms is unclear. This review summarizes recent findings regarding the PKA-mediated channel modulation and will highlight recently discovered regulatory mechanisms that are independent of PKA activity and involve protein-protein interactions and channel localization.


Assuntos
Canais de Cálcio Tipo L/metabolismo , Sinalização do Cálcio/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Miocárdio/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo , Animais , Sítios de Ligação , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Humanos , Fosforilação , Domínios e Motivos de Interação entre Proteínas
19.
Mol Cell ; 78(1): 42-56.e6, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32035036

RESUMO

The functional relevance and mechanistic basis of the effects of the neurotransmitter dopamine (DA) on inflammation remain unclear. Here we reveal that DA inhibited TLR2-induced NF-κB activation and inflammation via the DRD5 receptor in macrophages. We found that the DRD5 receptor, via the EFD and IYX(X)I/L motifs in its CT and IC3 loop, respectively, can directly recruit TRAF6 and its negative regulator ARRB2 to form a multi-protein complex also containing downstream signaling proteins, such as TAK1, IKKs, and PP2A, that impairs TRAF6-mediated activation of NF-κB and expression of pro-inflammatory genes. Furthermore, the DA-DRD5-ARRB2-PP2A signaling axis can prevent S. aureus-induced inflammation and protect mice against S. aureus-induced sepsis and meningitis after DA treatment. Collectively, these findings provide the first demonstration of DA-DRD5 signaling acting to control inflammation and a detailed delineation of the underlying mechanism and identify the DRD5-ARRB2-PP2A axis as a potential target for future therapy of inflammation-associated diseases such as meningitis and sepsis.


Assuntos
Dopamina/fisiologia , Inflamação/metabolismo , Proteína Fosfatase 2/metabolismo , Receptores de Dopamina D5/metabolismo , Transdução de Sinais , beta-Arrestina 2/metabolismo , Motivos de Aminoácidos , Animais , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Citocinas/genética , Citocinas/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Receptores de Dopamina D5/química , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Fator 6 Associado a Receptor de TNF/metabolismo , Receptor 2 Toll-Like/antagonistas & inibidores , beta-Arrestina 2/fisiologia
20.
Am J Physiol Renal Physiol ; 318(3): F793-F803, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32036696

RESUMO

Acute kidney injury has a high global morbidity associated with an increased risk of death and chronic kidney disease. Renal tubular epithelial cell regeneration following injury may be a decisive factor in renal repair or the progression of acute kidney injury to chronic kidney disease, but the underlying mechanism of abnormal renal tubular repair remains unclear. In the present study, we investigated the role of heterotrimeric G stimulatory protein α-subunit (Gsa) in renal tubular epithelial cell regeneration. We generated renal tubule epithelium-specific Gsa knockout (GsaKspKO) mice to show the essential role of Gsa in renal tubular epithelial cell regeneration in two AKI models: acute aristolochic acid nephropathy (AAN) and unilateral ischemia-reperfusion injury (UIRI). GsaKspKO mice developed more severe renal impairment after AAN and UIRI, higher serum creatinine levels, and more substantial tubular necrosis than wild-type mice. More importantly, Gsa inactivation impaired renal tubular epithelial cell proliferation by reducing bromodeoxyuridine+ cell numbers in the AAN model and inhibiting cyclin-dependent kinase 2/cyclin E1 expression in the UIRI model. This reduced proliferation was further supported in vitro with Gsa-targeting siRNA. Downregulation of Gsa inhibited tubular epithelial cell proliferation in HK-2 and mIMCD-3 cells. Furthermore, Gsa downregulation inhibited cyclin-dependent kinase 2/cyclin E1 expression, which was dependent on the Raf-MEK-ERK signaling pathway. In conclusion, Gsa is required for tubular epithelial cell regeneration during kidney repair after AKI. Loss of Gsa impairs renal tubular epithelial cell regeneration by blocking the Raf-MEK-ERK pathway.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Nefropatias/etiologia , Animais , Ácidos Aristolóquicos , Linhagem Celular , Proliferação de Células , Proteínas Quinases Dependentes de AMP Cíclico/genética , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Regulação para Baixo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Nefropatias/metabolismo , Túbulos Renais/citologia , Camundongos , Camundongos Knockout , Traumatismo por Reperfusão
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