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1.
Sci Data ; 10(1): 655, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749083

RESUMO

Advancing age is the greatest risk factor for developing multiple age-related diseases. Therapeutic approaches targeting the underlying pathways of ageing, rather than individual diseases, may be an effective way to treat and prevent age-related morbidity while reducing the burden of polypharmacy. We harness the Open Targets Genetics Portal to perform a systematic analysis of nearly 1,400 genome-wide association studies (GWAS) mapped to 34 age-related diseases and traits, identifying genetic signals that are shared between two or more of these traits. Using locus-to-gene (L2G) mapping, we identify 995 targets with shared genetic links to age-related diseases and traits, which are enriched in mechanisms of ageing and include known ageing and longevity-related genes. Of these 995 genes, 128 are the target of an approved or investigational drug, 526 have experimental evidence of binding pockets or are predicted to be tractable, and 341 have no existing tractability evidence, representing underexplored genes which may reveal novel biological insights and therapeutic opportunities. We present these candidate targets for exploration and prioritisation in a web application.


Assuntos
Envelhecimento , Estudo de Associação Genômica Ampla , Multimorbidade , Longevidade , Fenótipo , Envelhecimento/genética , Humanos
2.
J Pharmacol Exp Ther ; 334(3): 795-808, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20507928

RESUMO

Glucagon-like peptide-1 (GLP-1) mediates antidiabetogenic effects through the GLP-1 receptor (GLP-1R), which is targeted for the treatment of type 2 diabetes. Small-molecule GLP-1R agonists have been sought due to difficulties with peptide therapeutics. Recently, 6,7-dichloro-2-methylsulfonyl-3-N-tert-butylaminoquinoxaline (compound 2) has been described as a GLP-1R allosteric modulator and agonist. Using human embryonic kidney-293 cells expressing human GLP-1Rs, we extended this work to consider the impact of compound 2 on G protein activation, Ca(2+) signaling and receptor internalization and particularly to compare compound 2 and GLP-1 across a range of functional assays in intact cells. GLP-1 and compound 2 activated Galpha(s) in cell membranes and increased cellular cAMP in intact cells, with compound 2 being a partial and almost full agonist, respectively. GLP-1 increased intracellular [Ca(2+)] by release from intracellular stores, which was mimicked by compound 2, with slower kinetics. In either intact cells or membranes, the orthosteric antagonist exendin-(9-39), inhibited GLP-1 cAMP generation but increased the efficacy of compound 2. GLP-1 internalized enhanced green fluorescent protein-tagged GLP-1Rs, but the speed and magnitude evoked by compound 2 were less. Exendin-(9-39) inhibited internalization by GLP-1 and also surprisingly that by compound 2. Compound 2 displays GLP-1R agonism consistent with action at an allosteric site, although an orthosteric antagonist increased its efficacy on cAMP and blocked compound 2-mediated receptor internalization. Full assessment of the properties of compound 2 was potentially hampered by damaging effects that were particularly manifest in either longer term assays with intact cells or in acute assays with membranes.


Assuntos
Peptídeo 1 Semelhante ao Glucagon/farmacologia , Fragmentos de Peptídeos/farmacologia , Quinoxalinas/farmacologia , Receptores de Glucagon/efeitos dos fármacos , Sulfonas/farmacologia , Biotransformação/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Sobrevivência Celular , AMP Cíclico/metabolismo , Interpretação Estatística de Dados , Proteínas de Ligação ao GTP/metabolismo , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Receptor do Peptídeo Semelhante ao Glucagon 1 , Proteínas de Fluorescência Verde , Humanos , Ligantes , Fragmentos de Peptídeos/biossíntese , Receptores de Glucagon/biossíntese , Transdução de Sinais/efeitos dos fármacos , Azul Tripano
3.
J Pharmacol Exp Ther ; 330(2): 502-12, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19420300

RESUMO

Under physiological circumstances, cellular responses often reflect integration of signaling by two or more different receptors activated coincidentally or sequentially. In addition to heterologous desensitization, there are examples in which receptor activation either reveals or potentiates signaling by a different receptor type, although this is perhaps less well explored. Here, we characterize one such interaction between endogenous receptors in human embryonic kidney 293 cells in which Galpha(q/11)-coupled muscarinic M(3) receptors facilitate Ca(2+) signaling by Galpha(s)-coupled beta(2)-adrenoceptors. Measurement of changes in intracellular [Ca(2+)] demonstrated that noradrenaline released Ca(2+) from thapsigargin-sensitive intracellular stores only during activation of muscarinic receptors. Agonists with low efficacy for muscarinic receptor-mediated Ca(2+) responses facilitated cross-talk more effectively than full agonists. The cross-talk required Galpha(s) and was dependent upon intracellular Ca(2+) release channels, particularly inositol (1,4,5)-trisphosphate receptors. However, beta(2)-adrenoceptor-mediated Ca(2+) release was independent of measurable increases in phospholipase C activity and resistant to inhibitors of protein kinases A and C. Interestingly, single-cell imaging demonstrated that particularly lower concentrations of muscarinic receptor agonists facilitated marked oscillatory Ca(2+) signaling to noradrenaline. Thus, activation of muscarinic M(3) receptors profoundly influences the magnitude and oscillatory behavior of intracellular Ca(2+) signaling by beta(2)-adrenoceptors. Although these receptor subtypes are often coexpressed and mediate contrasting acute physiological effects, altered oscillatory Ca(2+) signaling suggests that cross-talk could influence longer term events through, for example, regulating gene transcription.


Assuntos
Relógios Biológicos/fisiologia , Sinalização do Cálcio/fisiologia , Agonismo Parcial de Drogas , Agonistas Muscarínicos/farmacologia , Receptor Muscarínico M3/agonistas , Receptor Muscarínico M3/fisiologia , Receptores Adrenérgicos beta 2/fisiologia , Relógios Biológicos/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Agonistas Muscarínicos/química , Receptor Cross-Talk/efeitos dos fármacos , Receptor Cross-Talk/fisiologia
4.
Biochem J ; 374(Pt 2): 281-96, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12790797

RESUMO

Alteration in [Ca(2+)](i) (the intracellular concentration of Ca(2+)) is a key regulator of many cellular processes. To allow precise regulation of [Ca(2+)](i) and a diversity of signalling by this ion, cells possess many mechanisms by which they are able to control [Ca(2+)](i) both globally and at the subcellular level. Among these are many members of the superfamily of GPCRs (G-protein-coupled receptors), which are characterized by the presence of seven transmembrane domains. Typically, those receptors able to activate PLC (phospholipase C) enzymes cause release of Ca(2+) from intracellular stores and influence Ca(2+) entry across the plasma membrane. It has been well documented that Ca(2+) signalling by one type of GPCR can be influenced by stimulation of a different type of GPCR. Indeed, many studies have demonstrated heterologous desensitization between two different PLC-coupled GPCRs. This is not surprising, given our current understanding of negative-feedback regulation and the likely shared components of the signalling pathway. However, there are also many documented examples of interactions between GPCRs, often coupling preferentially to different signalling pathways, which result in a potentiation of Ca(2+) signalling. Such interactions have important implications for both the control of cell function and the interpretation of in vitro cell-based assays. However, there is currently no single mechanism that adequately accounts for all examples of this type of cross-talk. Indeed, many studies either have not addressed this issue or have been unable to determine the mechanism(s) involved. This review seeks to explore a range of possible mechanisms to convey their potential diversity and to provide a basis for further experimental investigation.


Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/fisiologia , Proteínas de Ligação ao GTP/fisiologia , Receptor Cross-Talk/fisiologia , Receptores de Superfície Celular/fisiologia , Animais , Proteínas de Ligação ao GTP/metabolismo , Humanos
6.
J Biomol Screen ; 20(2): 167-79, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25527136

RESUMO

Drug repositioning or repurposing has received much coverage in the scientific literature in recent years and has been responsible for the generation of both new intellectual property and investigational new drug submissions. The literature indicates a significant trend toward the use of computational- or informatics-based methods for generating initial repositioning hypotheses, followed by focused assessment of biological activity in phenotypic assays. Another viable method for drug repositioning is in vitro screening of known drugs or drug-like molecules, initially in disease-relevant phenotypic assays, to identify and validate candidates for repositioning. This approach can use large compound libraries or can focus on subsets of known drugs or drug-like molecules. In this short review, we focus on ways to generate and validate repositioning candidates in disease-related in vitro and phenotypic assays, and we discuss specific examples of this approach as applied to a variety of disease areas. We propose that in vitro screens offer several advantages over biochemical or in vivo methods as a starting point for drug repositioning.


Assuntos
Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Técnicas In Vitro , Animais , Bioensaio , Biologia Computacional/métodos , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos
7.
Br J Pharmacol ; 135(5): 1199-208, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11877327

RESUMO

1. Human embryonic kidney (HEK)-293 cells expressing recombinant G alpha(i)-coupled, human CXC chemokine receptor 2 (CXCR2) were used to study the elevation of the intracellular [Ca(2+)] ([Ca(2+)](i)) in response to interleukin-8 (IL-8) following pre-stimulation of endogenously expressed P2Y1 or P2Y2 nucleotide receptors. 2. Pre-stimulation of cells with adenosine 5'-triphosphate (ATP) revealed a substantial Ca(2+) signalling component mediated by IL-8 (E(max)=83 +/- 8% of maximal ATP response, pEC(50) of IL-8 response=9.7 +/- 0.1). 3. 1 microM 2-methylthioadenosine 5'-diphosphate (2MeSADP; P2Y1 selective) and 100 microM uridine 5'-triphosphate (UTP; P2Y2 selective) stimulated equivalent maximal increases in [Ca(2+)](i) elevation. However, UTP caused a sustained elevation, whilst following 2MeSADP [Ca(2+)](i) rapidly returned to basal levels. 4. Both UTP and 2MeSADP increased the potency and magnitude of IL-8-mediated [Ca(2+)](i) elevation but the effects of UTP (E(max) of IL-8 response increased to 50 +/- 1% of the maximal response to ATP, pEC(50) increased to 9.8 +/- 0.1) were greater than those of 2MeSADP (E(max) increased to 36 +/- 2%, pEC(50) increased to 8.7 +/- 0.2). 5. 5. The potentiation of IL-8-mediated Ca(2+) signalling by UTP was not dependent upon the time of IL-8 addition following UTP but was dependent on the continued presence of UTP. Potentiated IL-8 Ca(2+) signalling was apparent in the absence of extracellular Ca(2+), demonstrating the release of Ca(2+) from intracellular stores. 6. Activation of P2Y1 and P2Y2 receptors also revealed Ca(2+) signalling by an endogenously expressed, G alpha(s)-coupled beta-adrenoceptor. 7. In conclusion, pre-stimulation of P2Y nucleotide receptors, particularly P2Y2, facilitates Ca(2+) signalling by either recombinant CXCR2 or endogenous beta-adrenoceptors.


Assuntos
Sinalização do Cálcio/fisiologia , Receptores de Interleucina-8B/fisiologia , Receptores Purinérgicos P2/fisiologia , Trifosfato de Adenosina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Humanos , Agonistas do Receptor Purinérgico P2 , Receptor Cross-Talk , Receptores de Interleucina-8B/metabolismo , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2Y1 , Receptores Purinérgicos P2Y2 , Proteínas Recombinantes/metabolismo
8.
J Pharmacol Exp Ther ; 307(2): 661-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12975484

RESUMO

We have shown previously that activation of endogenously expressed, Galphaq/11-coupled P2Y2 nucleotide receptors with UTP reveals an intracellular Ca2+ response to activation of recombinant, Galphai-coupled CXC chemokine receptor 2 (CXCR2) in human embryonic kidney cells. Here, we characterize further this cross talk and demonstrate that phospholipase C (PLC) and inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]-dependent Ca2+ release underlies this potentiation. The putative Ins(1,4,5)P3 receptor antagonist 2-aminoethoxydiphenyl borane reduced the response to CXCR2 activation by interleukin-8, as did sustained inhibition of phosphatidylinositol 4-kinase with wortmannin, suggesting the involvement of phosphoinositides in the potentiation. Against a Li+ block of inositol monophosphatase activity, costimulation of P2Y2 nucleotide receptors and CXCR2 caused phosphoinositide accumulation that was significantly greater than that after activation of P2Y2 nucleotide receptors or CXCR2 alone, and was more than additive. Thus, PLC activity, as well as Ca2+ release, was enhanced. In these cells, agonist-mediated Ca2+ release was incremental in nature, suggesting that a potentiation of Ins(1,4,5)P3 generation in the presence of coactivation of P2Y2 nucleotide receptors and CXCR2 would be sufficient for additional Ca2+ release. Potentiated Ca2+ signaling by CXCR2 was markedly attenuated by expression of either regulator of G protein signaling 2 or the Gbetagamma-scavenger Galphat1 (transducin alpha subunit), indicating the involvement of Galphaq and Gbetagamma subunits, respectively.


Assuntos
Cálcio/metabolismo , Receptores de Interleucina-8B/metabolismo , Receptores Purinérgicos P2/metabolismo , Transdução de Sinais/fisiologia , Fosfolipases Tipo C/metabolismo , 1-Fosfatidilinositol 4-Quinase/antagonistas & inibidores , Compostos de Boro/farmacologia , Sinalização do Cálcio , Células Cultivadas , Proteínas de Ligação ao GTP/metabolismo , Humanos , Fosfatos de Inositol/metabolismo , Interleucina-8/farmacologia , Rim/citologia , Rim/embriologia , Monoéster Fosfórico Hidrolases/metabolismo , Proteína Quinase C/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas RGS/genética , Proteínas RGS/farmacologia , Receptor Cross-Talk , Receptores Purinérgicos P2Y2 , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tapsigargina/farmacologia , Uridina Trifosfato/farmacologia
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