RESUMEN
Pharmacokinetic properties and duration of therapeutic action of a pharmaceutical agent can be significantly extended through the combination of two distinct strategies aimed at increasing plasma half-life: fatty acid acylation and Fc-conjugation. Using insulin as a case study, we demonstrate that a doubly protracted insulin analog produces a substantial prolongation of pharmacodynamic effect to lower blood glucose in STZ-treated mice when compared to the Fc-only counterparts. This enhancement is further corroborated by direct pharmacokinetic measurements in rat and dog models, demonstrating the potential for once-monthly insulin therapy. The results suggest that this approach might have broad application across a diverse spectrum of peptide- and protein-based therapeutics.
RESUMEN
For more than a century, physicians have searched for ways to pharmacologically reduce excess body fat. The tide has finally turned with recent advances in biochemically engineered agonists for the receptor of glucagon-like peptide-1 (GLP-1) and their use in GLP-1-based polyagonists. These polyagonists reduce body weight through complementary pharmacology by incorporating the receptors for glucagon and/or the glucose-dependent insulinotropic polypeptide (GIP). In their most advanced forms, gut-hormone polyagonists achieve an unprecedented weight reduction of up to â¼20%-30%, offering a pharmacological alternative to bariatric surgery. Along with favorable effects on glycemia, fatty liver, and kidney disease, they also offer beneficial effects on the cardiovascular system and adipose tissue. These new interventions, therefore, hold great promise for the future of anti-obesity medications.
Asunto(s)
Fármacos Antiobesidad , Obesidad , Humanos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Fármacos Antiobesidad/uso terapéutico , Fármacos Antiobesidad/farmacología , Animales , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Tejido Adiposo/metabolismo , Tejido Adiposo/efectos de los fármacosRESUMEN
The N-methyl-D-aspartate (NMDA) receptor is a glutamate-activated cation channel that is critical to many processes in the brain. Genome-wide association studies suggest that glutamatergic neurotransmission and NMDA receptor-mediated synaptic plasticity are important for body weight homeostasis1. Here we report the engineering and preclinical development of a bimodal molecule that integrates NMDA receptor antagonism with glucagon-like peptide-1 (GLP-1) receptor agonism to effectively reverse obesity, hyperglycaemia and dyslipidaemia in rodent models of metabolic disease. GLP-1-directed delivery of the NMDA receptor antagonist MK-801 affects neuroplasticity in the hypothalamus and brainstem. Importantly, targeting of MK-801 to GLP-1 receptor-expressing brain regions circumvents adverse physiological and behavioural effects associated with MK-801 monotherapy. In summary, our approach demonstrates the feasibility of using peptide-mediated targeting to achieve cell-specific ionotropic receptor modulation and highlights the therapeutic potential of unimolecular mixed GLP-1 receptor agonism and NMDA receptor antagonism for safe and effective obesity treatment.
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Maleato de Dizocilpina , Péptido 1 Similar al Glucagón , Receptor del Péptido 1 Similar al Glucagón , Obesidad , Receptores de N-Metil-D-Aspartato , Animales , Humanos , Masculino , Ratones , Ratas , Tronco Encefálico/metabolismo , Tronco Encefálico/efectos de los fármacos , Modelos Animales de Enfermedad , Maleato de Dizocilpina/efectos adversos , Maleato de Dizocilpina/farmacología , Maleato de Dizocilpina/uso terapéutico , Dislipidemias/tratamiento farmacológico , Dislipidemias/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Hiperglucemia/tratamiento farmacológico , Hiperglucemia/metabolismo , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Ratones Endogámicos C57BL , Plasticidad Neuronal/efectos de los fármacos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Ratas Sprague-Dawley , Ratas Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidoresRESUMEN
The development of single-molecule co-agonists for the glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) is considered a breakthrough in the treatment of obesity and type 2 diabetes. But although GIPR-GLP-1R co-agonism decreases body weight with superior efficacy relative to GLP-1R agonism alone in preclinical1-3 and clinical studies4,5, the role of GIP in regulating energy metabolism remains enigmatic. Increasing evidence suggests that long-acting GIPR agonists act in the brain to decrease body weight through the inhibition of food intake3,6-8; however, the mechanisms and neuronal populations through which GIP affects metabolism remain to be identified. Here, we report that long-acting GIPR agonists and GIPR-GLP-1R co-agonists decrease body weight and food intake via inhibitory GABAergic neurons. We show that acyl-GIP decreases body weight and food intake in male diet-induced obese wild-type mice, but not in mice with deletion of Gipr in Vgat(also known as Slc32a1)-expressing GABAergic neurons (Vgat-Gipr knockout). Whereas the GIPR-GLP-1R co-agonist MAR709 leads, in male diet-induced obese wild-type mice, to greater weight loss and further inhibition of food intake relative to a pharmacokinetically matched acyl-GLP-1 control, this superiority over GLP-1 vanishes in Vgat-Gipr knockout mice. Our data demonstrate that long-acting GIPR agonists crucially depend on GIPR signaling in inhibitory GABAergic neurons to decrease body weight and food intake.
Asunto(s)
Diabetes Mellitus Tipo 2 , Masculino , Ratones , Animales , Diabetes Mellitus Tipo 2/metabolismo , Polipéptido Inhibidor Gástrico/metabolismo , Obesidad/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Receptores Acoplados a Proteínas G , Glucosa , Neuronas GABAérgicas/metabolismo , Ingestión de AlimentosRESUMEN
The incretin system is an essential metabolic axis that regulates postprandial metabolism. The two incretin peptides that enable this effect are the glucose-dependent insulinotropic polypeptide (GIP) and the glucagon-like peptide 1 (GLP-1), which have cognate receptors (GIPR and GLP-1R) on islet ß cells as well as in other tissues. Pharmacologic engagement of the GLP-1R is a proven strategy for treating hyperglycemia in diabetes and reducing body weight. Tirzepatide is the first monomeric peptide with dual activity at both incretin receptors now available for clinical use, and in clinical trials it has shown unprecedented effects to reduce blood glucose and body weight. Here, we discuss the foundational science that led to the development of monomeric multi-incretin receptor agonists, culminating in the development of tirzepatide. We also look to the future of this field and comment on how the concept of multi-receptor agonists will continue to progress for the treatment of metabolic disease.
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Diabetes Mellitus , Hiperglucemia , Humanos , Incretinas/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Pérdida de Peso , Peso Corporal , Receptores Acoplados a Proteínas GRESUMEN
BACKGROUND: Agonism at the receptor for the glucose-dependent insulinotropic polypeptide (GIPR) is a key component of the novel unimolecular GIPR:GLP-1R co-agonists, which are among the most promising drugs in clinical development for the treatment of obesity and type 2 diabetes. The therapeutic effect of chronic GIPR agonism to treat dyslipidemia and thus to reduce the cardiovascular disease risk independently of body weight loss has not been explored yet. METHODS: After 8 weeks on western diet, LDL receptor knockout (LDLR-/-) male mice were treated with daily subcutaneous injections of long-acting acylated GIP analog (acyl-GIP; 10nmol/kg body weight) for 28 days. Body weight, food intake, whole-body composition were monitored throughout the study. Fasting blood glucose and intraperitoneal glucose tolerance test (ipGTT) were determined on day 21 of the study. Circulating lipid levels, lipoprotein profiles and atherosclerotic lesion size was assessed at the end of the study. Acyl-GIP effects on fat depots were determined by histology and transcriptomics. RESULTS: Herein we found that treatment with acyl-GIP reduced dyslipidemia and atherogenesis in male LDLR-/- mice. Acyl-GIP administration resulted in smaller adipocytes within the inguinal fat depot and RNAseq analysis of the latter revealed that acyl-GIP may improve dyslipidemia by directly modulating lipid metabolism in this fat depot. CONCLUSIONS: This study identified an unanticipated efficacy of chronic GIPR agonism to improve dyslipidemia and cardiovascular disease independently of body weight loss, indicating that treatment with acyl-GIP may be a novel approach to alleviate cardiometabolic disease.
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Aterosclerosis , Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Dislipidemias , Masculino , Animales , Ratones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/genética , Aterosclerosis/prevención & control , Dislipidemias/tratamiento farmacológico , Peso Corporal , Pérdida de PesoRESUMEN
Lymphocystis disease virus-1 (LCDV-1) and several other Iridoviridae encode viral insulin/IGF-1 like peptides (VILPs) with high homology to human insulin and IGFs. Here we show that while single-chain (sc) and double-chain (dc) LCDV1-VILPs have very low affinity for the insulin receptor, scLCDV1-VILP has high affinity for IGF1R where it can antagonize human IGF-1 signaling, without altering insulin signaling. Consequently, scLCDV1-VILP inhibits IGF-1 induced cell proliferation and growth hormone/IGF-1 induced growth of mice in vivo. Cryo-electron microscopy reveals that scLCDV1-VILP engages IGF1R in a unique manner, inducing changes in IGF1R conformation that led to separation, rather than juxtaposition, of the transmembrane segments and hence inactivation of the receptor. Thus, scLCDV1-VILP is a natural peptide with specific antagonist properties on IGF1R signaling and may provide a new tool to guide development of hormonal analogues to treat cancers or metabolic disorders sensitive to IGF-1 without affecting glucose metabolism.
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Factor I del Crecimiento Similar a la Insulina , Receptor IGF Tipo 1 , Humanos , Ratones , Animales , Receptor IGF Tipo 1/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Insulina/metabolismo , Microscopía por Crioelectrón , Péptidos/farmacologíaRESUMEN
OBJECTIVE: The Allan-Herndon-Dudley syndrome (AHDS) is a severe disease caused by dysfunctional central thyroid hormone transport due to functional loss of the monocarboxylate transporter 8 (MCT8). In this study, we assessed whether mice with concomitant deletion of the thyroid hormone transporters Mct8 and the organic anion transporting polypeptide (Oatp1c1) represent a valid preclinical model organism for the AHDS. METHODS: We generated and metabolically characterized a new CRISPR/Cas9 generated Mct8/Oatp1c1 double-knockout (dKO) mouse line for the clinical features observed in patients with AHDS. RESULTS: We show that Mct8/Oatp1c1 dKO mice mimic key hallmarks of the AHDS, including decreased life expectancy, central hypothyroidism, peripheral hyperthyroidism, impaired neuronal myelination, impaired motor abilities and enhanced peripheral thyroid hormone action in the liver, adipose tissue, skeletal muscle and bone. CONCLUSIONS: We conclude that Mct8/Oatp1c1 dKO mice are a valuable model organism for the preclinical evaluation of drugs designed to treat the AHDS.
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Discapacidad Intelectual Ligada al Cromosoma X , Simportadores , Animales , Ratones , Transportadores de Ácidos Monocarboxílicos/genética , Simportadores/genética , Discapacidad Intelectual Ligada al Cromosoma X/genética , Hormonas TiroideasRESUMEN
Dual agonists activating the peroxisome proliferator-activated receptors alpha and gamma (PPARÉ/É£) have beneficial effects on glucose and lipid metabolism in patients with type 2 diabetes, but their development was discontinued due to potential adverse effects. Here we report the design and preclinical evaluation of a molecule that covalently links the PPARÉ/É£ dual-agonist tesaglitazar to a GLP-1 receptor agonist (GLP-1RA) to allow for GLP-1R-dependent cellular delivery of tesaglitazar. GLP-1RA/tesaglitazar does not differ from the pharmacokinetically matched GLP-1RA in GLP-1R signalling, but shows GLP-1R-dependent PPARÉ£-retinoic acid receptor heterodimerization and enhanced improvements of body weight, food intake and glucose metabolism relative to the GLP-1RA or tesaglitazar alone in obese male mice. The conjugate fails to affect body weight and glucose metabolism in GLP-1R knockout mice and shows preserved effects in obese mice at subthreshold doses for the GLP-1RA and tesaglitazar. Liquid chromatography-mass spectrometry-based proteomics identified PPAR regulated proteins in the hypothalamus that are acutely upregulated by GLP-1RA/tesaglitazar. Our data show that GLP-1RA/tesaglitazar improves glucose control with superior efficacy to the GLP-1RA or tesaglitazar alone and suggest that this conjugate might hold therapeutic value to acutely treat hyperglycaemia and insulin resistance.
Asunto(s)
Diabetes Mellitus Tipo 2 , PPAR alfa , Alcanosulfonatos , Animales , Peso Corporal , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón/uso terapéutico , Receptor del Péptido 1 Similar al Glucagón , Glucosa , Masculino , Ratones , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , PPAR alfa/agonistas , PPAR alfa/uso terapéutico , FenilpropionatosRESUMEN
OBJECTIVE: Pharmacological strategies that engage multiple mechanisms-of-action have demonstrated synergistic benefits for metabolic disease in preclinical models. One approach, concurrent activation of the glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon (Gcg) receptors (i.e. triagonism), combines the anorectic and insulinotropic activities of GLP-1 and GIP with the energy expenditure effect of glucagon. While the efficacy of triagonism in preclinical models is known, the relative contribution of GcgR activation remains unassessed. This work aims to addresses that central question. METHODS: Herein, we detail the design of unimolecular peptide triagonists with an empirically optimized receptor potency ratio. These optimized peptide triagonists employ a protraction strategy permitting once-weekly human dosing. Additionally, we assess the effects of these peptides on weight-reduction, food intake, glucose control, and energy expenditure in an established DIO mouse model compared to clinically relevant GLP-1R agonists (e.g. semaglutide) and dual GLP-1R/GIPR agonists (e.g. tirzepatide). RESULTS: Optimized triagonists normalize body weight in DIO mice and enhance energy expenditure in a manner superior to that of GLP-1R mono-agonists and GLP-1R/GIPR co-agonists. CONCLUSIONS: These pre-clinical data suggest unimolecular poly-pharmacology as an effective means to target multiple mechanisms contributing to obesity and further implicate GcgR activation as the differentiating factor between incretin receptor mono- or dual-agonists and triagonists.
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Polipéptido Inhibidor Gástrico , Glucagón , Animales , Peso Corporal , Polipéptido Inhibidor Gástrico/metabolismo , Glucagón/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Humanos , Ratones , Ratones Obesos , Péptidos/farmacología , Receptores de Glucagón/metabolismoRESUMEN
We study the efficacy of a glucagon-like peptide-1 (GLP-1) and estrogen dual agonist (GLP1-E2) in pancreatic islet protection. GLP1-E2 provides superior protection from insulin-deficient diabetes induced by multiple low-dose streptozotocin (MLD-STZ-diabetes) and by the Akita mutation in mice than a GLP-1 monoagonist. GLP1-E2 does not protect from MLD-STZ-diabetes in estrogen receptor-α (ERα)-deficient mice and fails to prevent diabetes in Akita mice following GLP-1 receptor (GLP-1R) antagonism, demonstrating the requirement of GLP-1R and ERα for GLP1-E2 antidiabetic actions. In the MIN6 ß cell model, GLP1-E2 activates estrogen action following clathrin-dependent, GLP-1R-mediated internalization and lysosomal acidification. In cultured human islet, proteomic bioinformatic analysis reveals that GLP1-E2 amplifies the antiapoptotic pathways activated by monoagonists. However, in cultured mouse islets, GLP1-E2 provides antiapoptotic protection similar to monoagonists. Thus, GLP1-E2 promotes GLP-1 and E2 antiapoptotic signals in cultured islets, but in vivo, additional GLP1-E2 actions in non-islet cells expressing GLP-1R are instrumental to prevent diabetes.
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Diabetes Mellitus , Islotes Pancreáticos , Animales , Diabetes Mellitus/metabolismo , Receptor alfa de Estrógeno/metabolismo , Estrógenos/metabolismo , Péptido 1 Similar al Glucagón/farmacología , Insulina/metabolismo , Insulina Regular Humana/metabolismo , Islotes Pancreáticos/metabolismo , Ratones , Proteómica , Estreptozocina/toxicidadRESUMEN
Zinc (Zn) is an essential micronutrient and cofactor for up to 10% of proteins in living organisms. During Zn limitation, specialized enzymes called metallochaperones are predicted to allocate Zn to specific metalloproteins. This function has been putatively assigned to G3E GTPase COG0523 proteins, yet no Zn metallochaperone has been experimentally identified in any organism. Here, we functionally characterize a family of COG0523 proteins that is conserved across vertebrates. We identify Zn metalloprotease methionine aminopeptidase 1 (METAP1) as a COG0523 client, leading to the redesignation of this group of COG0523 proteins as the Zn-regulated GTPase metalloprotein activator (ZNG1) family. Using biochemical, structural, genetic, and pharmacological approaches across evolutionarily divergent models, including zebrafish and mice, we demonstrate a critical role for ZNG1 proteins in regulating cellular Zn homeostasis. Collectively, these data reveal the existence of a family of Zn metallochaperones and assign ZNG1 an important role for intracellular Zn trafficking.
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Metaloendopeptidasas/metabolismo , Zinc , Animales , GTP Fosfohidrolasas/metabolismo , Homeostasis , Metalochaperonas/metabolismo , Metaloproteínas/genética , Ratones , Pez Cebra/metabolismo , Zinc/metabolismoRESUMEN
Toxic misfolding of proinsulin variants in ß-cells defines a monogenic diabetes syndrome, designated mutant INS-gene induced diabetes of the young (MIDY). In our first study (previous article in this issue), we described a one-disulfide peptide model of a proinsulin folding intermediate and its use to study such variants. The mutations (LeuB15âPro, LeuA16âPro, and PheB24âSer) probe residues conserved among vertebrate insulins. In this companion study, we describe 1H and 1H-13C NMR studies of the peptides; key NMR resonance assignments were verified by synthetic 13C-labeling. Parent spectra retain nativelike features in the neighborhood of the single disulfide bridge (cystine B19-A20), including secondary NMR chemical shifts and nonlocal nuclear Overhauser effects. This partial fold engages wild-type side chains LeuB15, LeuA16 and PheB24 at the nexus of nativelike α-helices α1 and α3 (as defined in native proinsulin) and flanking ß-strand (residues B24-B26). The variant peptides exhibit successive structural perturbations in order: parent (most organized) > SerB24 >> ProA16 > ProB15 (least organized). The same order pertains to (a) overall α-helix content as probed by circular dichroism, (b) synthetic yields of corresponding three-disulfide insulin analogs, and (c) ER stress induced in cell culture by corresponding mutant proinsulins. These findings suggest that this and related peptide models will provide a general platform for classification of MIDY mutations based on molecular mechanisms by which nascent disulfide pairing is impaired. We propose that the syndrome's variable phenotypic spectrum-onsets ranging from the neonatal period to later in childhood or adolescence-reflects structural features of respective folding intermediates.
Asunto(s)
Diabetes Mellitus , Proinsulina , Adolescente , Diabetes Mellitus/genética , Disulfuros/química , Humanos , Recién Nacido , Insulina/química , Proinsulina/química , Proinsulina/genética , Pliegue de ProteínaRESUMEN
The mutant proinsulin syndrome is a monogenic cause of diabetes mellitus due to toxic misfolding of insulin's biosynthetic precursor. Also designated mutant INS-gene induced diabetes of the young (MIDY), this syndrome defines molecular determinants of foldability in the endoplasmic reticulum (ER) of ß-cells. Here, we describe a peptide model of a key proinsulin folding intermediate and variants containing representative clinical mutations; the latter perturb invariant core sites in native proinsulin (LeuB15âPro, LeuA16âPro, and PheB24âSer). The studies exploited a 49-residue single-chain synthetic precursor (designated DesDi), previously shown to optimize in vitro efficiency of disulfide pairing. Parent and variant peptides contain a single disulfide bridge (cystine B19-A20) to provide a model of proinsulin's first oxidative folding intermediate. The peptides were characterized by circular dichroism and redox stability in relation to effects of the mutations on (a) in vitro foldability of the corresponding insulin analogs and (b) ER stress induced in cell culture on expression of the corresponding variant proinsulins. Striking correlations were observed between peptide biophysical properties, degree of ER stress and age of diabetes onset (neonatal or adolescent). Our findings suggest that age of onset reflects the extent to which nascent structure is destabilized in proinsulin's putative folding nucleus. We envisage that such peptide models will enable high-resolution structural studies of key folding determinants and in turn permit molecular dissection of phenotype-genotype relationships in this monogenic diabetes syndrome. Our companion study (next article in this issue) employs two-dimensional heteronuclear NMR spectroscopy to define site-specific perturbations in the variant peptides.
Asunto(s)
Diabetes Mellitus , Proinsulina , Adolescente , Diabetes Mellitus/metabolismo , Disulfuros/química , Disulfuros/metabolismo , Humanos , Insulina/metabolismo , Péptidos , Proinsulina/química , Proinsulina/genética , Proinsulina/metabolismo , Pliegue de ProteínaRESUMEN
The incretin hormone glucagon-like peptide-1 (GLP-1) has received enormous attention during the past three decades as a therapeutic target for the treatment of obesity and type 2 diabetes. Continuous improvement of the pharmacokinetic profile of GLP-1R agonists, starting from native hormone with a half-life of ~2-3 min to the development of twice daily, daily and even once-weekly drugs highlight the pharmaceutical evolution of GLP-1-based medicines. In contrast to GLP-1, the incretin hormone glucose-dependent insulinotropic polypeptide (GIP) received little attention as a pharmacological target, because of conflicting observations that argue activation or inhibition of the GIP receptor (GIPR) provides beneficial effects on systemic metabolism. Interest in GIPR agonism for the treatment of obesity and diabetes was recently propelled by the clinical success of unimolecular dual-agonists targeting the receptors for GIP and GLP-1, with reported significantly improved body weight and glucose control in patients with obesity and type II diabetes. Here we review the biology and pharmacology of GLP-1 and GIP and discuss recent advances in incretin-based pharmacotherapies.
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Diabetes Mellitus Tipo 2 , Incretinas , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Polipéptido Inhibidor Gástrico , Péptido 1 Similar al Glucagón/metabolismo , Receptor del Péptido 1 Similar al Glucagón/agonistas , Humanos , Incretinas/uso terapéutico , Obesidad/tratamiento farmacológico , Obesidad/metabolismoRESUMEN
Enormous progress has been made in the last half-century in the management of diseases closely integrated with excess body weight, such as hypertension, adult-onset diabetes and elevated cholesterol. However, the treatment of obesity itself has proven largely resistant to therapy, with anti-obesity medications (AOMs) often delivering insufficient efficacy and dubious safety. Here, we provide an overview of the history of AOM development, focusing on lessons learned and ongoing obstacles. Recent advances, including increased understanding of the molecular gut-brain communication, are inspiring the pursuit of next-generation AOMs that appear capable of safely achieving sizeable and sustained body weight loss.
Asunto(s)
Fármacos Antiobesidad , Diabetes Mellitus Tipo 2 , Adulto , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Humanos , Obesidad/tratamiento farmacológico , Pérdida de PesoRESUMEN
Optimization of peptides for therapeutic purposes often includes chemical conjugation or modification with substituents that serve to broaden pharmacology or improve pharmacokinetics. We report a convenient and rapid procedure for one-pot, site-specific conjugation of two cysteine-containing peptides that utilizes a bivalent linker comprising maleimide and iodoacetyl functional groups. Following maleimide-mediated peptide conjugation the linker was converted from an unstable thiosuccinimide to a stable thioether bond suitable for biological study by mild aqueous hydrolysis. The procedure is exemplified by peptide-peptide, peptide-small molecule, and peptide-fatty acid conjugations. The method provides a facile approach to search for enhanced biological outcomes through additive and sustained peptide pharmacology unencumbered by the prospect of chemical rearrangement in the course of biological study.
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Cisteína/química , Polímeros/síntesis química , Proglucagón/química , Secuencia de Aminoácidos , Animales , Células Cultivadas , Cricetinae , Cisteína/análogos & derivados , Receptor del Péptido 1 Similar al Glucagón/agonistas , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Humanos , Maleimidas/química , Fenómenos Químicos Orgánicos , Péptidos/síntesis química , Péptidos/química , Polímeros/químicaRESUMEN
OBJECTIVE: Natural sources of molecular diversity remain of utmost importance as a reservoir of proteins and peptides with unique biological functions. We recently identified such a family of viral insulin-like peptides (VILPs). We sought to advance the chemical methods in synthesis to explore the structure-function relationship within these VILPs, and the molecular basis for differential biological activities relative to human IGF-1 and insulin. METHODS: Optimized chemical methods in synthesis were established for a set of VILPs and related analogs. These modified forms included the substitution of select VILP chains with those derived from human insulin and IGF-1. Each peptide was assessed in vitro for agonism and antagonism at the human insulin and the human insulin-like growth factor 1 receptor (IGF-1R). RESULTS: We report here that one of these VILPs, lymphocystis disease virus-1 (LCDV1)-VILP, has the unique property to be a potent and full antagonist of the IGF-1R. We demonstrate the coordinated importance of the B- and C-chains of the VILP in regulating this activity. Moreover, mutation of the glycine following the first cysteine in the B-chain of IGF-1 to serine, in concert with substitution to the connecting peptide of LCDV1-VILP, converted native IGF-1 to a high potency antagonist. CONCLUSIONS: The results reveal novel aspects in ligand-receptor interactions at the IGF-1 receptor and identify a set of antagonists of potential medicinal importance.
Asunto(s)
Iridoviridae/química , Neuropéptidos/farmacología , Receptor IGF Tipo 1/antagonistas & inhibidores , Humanos , Neuropéptidos/química , Receptor IGF Tipo 1/metabolismoRESUMEN
Basal glucose control is commonly maintained by a single, once-daily administration of insulin through subcutaneous injection or a continuous pump-infusion. Insulin icodec, a novel ultralong-acting lipidated analog validates the concept of a once-weekly basal injection that is less burdensome, yet equally safe and efficacious as conventional once-daily treatment.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Glucemia , Diabetes Mellitus Tipo 2/metabolismo , Esquema de Medicación , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/química , Infusiones Subcutáneas , Insulina/administración & dosificación , Insulina/análogos & derivadosRESUMEN
Antagonism of glucagon's biological action is a proven strategy for decreasing glucose in diabetic animals and patients. To achieve full, potent, and selective suppression, we chemically optimized N-terminally truncated glucagon fragments for the identification and establishment of the minimum sequence peptide, [Glu9]glucagon(6-29) amide (11) as a full antagonist in cellular signaling and receptor binding (IC50 = 36 nM). Substitution of Phe6 with l-3-phenyllactic acid (Pla) produced [Pla6, Glu9]glucagon(6-29) amide (21), resulting in a 3-fold improvement in receptor binding (IC50 = 12 nM) and enhanced antagonist potency. Further substitution of Glu9 and Asn28 with aspartic acid yielded [Pla6, Asp28]glucagon amide (26), which demonstrated a further increase in inhibitory potency (IC50 = 9 nM), and improved aqueous solubility. Peptide 26 and a palmitoylated analogue, [Pla6, Lys10(γGluγGlu-C16), Asp28]glucagon(6-29) amide (31), displayed sustained duration in vivo action that successfully reversed glucagon-induced glucose elevation in mice.