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1.
N Engl J Med ; 388(15): 1376-1385, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37043653

RESUMEN

BACKGROUND: Erythropoietic protoporphyria and X-linked protoporphyria are inborn errors of heme biosynthesis that cause elevated circulating levels of metal-free protoporphyrin and phototoxicity. Both disorders are characterized by excruciating phototoxic attacks after exposure to visible light. Dersimelagon is a new, orally administered, selective melanocortin 1 receptor agonist that increases levels of skin eumelanin. METHODS: We conducted a randomized, placebo-controlled, phase 2 trial to investigate the efficacy and safety of dersimelagon with respect to the time to onset and the severity of symptoms associated with sunlight exposure in patients with erythropoietic protoporphyria or X-linked protoporphyria. Patients 18 to 75 years of age were randomly assigned in a 1:1:1 ratio to receive placebo or dersimelagon at a dose of 100 or 300 mg once daily for 16 weeks. The primary end point was the change from baseline to week 16 in the time to the first prodromal symptom associated with sunlight exposure. Patients recorded daily sunlight exposure and symptom data in an electronic diary. Quality of life and safety were also assessed. RESULTS: Of the 102 patients (93 with erythropoietic protoporphyria and 9 with X-linked protoporphyria) who underwent randomization, 90% completed the treatment period. The mean daily time to the first prodromal symptom associated with sunlight exposure increased significantly with dersimelagon: the least-squares mean difference from placebo in the change from baseline to week 16 was 53.8 minutes in the 100-mg dersimelagon group (P = 0.008) and 62.5 minutes in the 300-mg dersimelagon group (P = 0.003). The results also suggest that quality of life improved in patients receiving dersimelagon as compared with placebo. The most common adverse events that occurred or worsened during treatment were nausea, freckles, headache, and skin hyperpigmentation. CONCLUSIONS: At both doses evaluated, dersimelagon significantly increased the duration of symptom-free sunlight exposure in patients with erythropoietic protoporphyria or X-linked protoporphyria. (Funded by Mitsubishi Tanabe Pharma; Endeavor ClinicalTrials.gov number, NCT03520036.).


Asunto(s)
Fármacos Dermatológicos , Trastornos por Fotosensibilidad , Protoporfiria Eritropoyética , Receptor de Melanocortina Tipo 1 , Humanos , Recién Nacido , Síntomas Prodrómicos , Protoporfiria Eritropoyética/complicaciones , Protoporfiria Eritropoyética/tratamiento farmacológico , Calidad de Vida , Piel/efectos de los fármacos , Luz/efectos adversos , Trastornos por Fotosensibilidad/etiología , Receptor de Melanocortina Tipo 1/agonistas , Administración Oral , Fármacos Dermatológicos/uso terapéutico
2.
J Am Soc Nephrol ; 34(3): 467-481, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36446431

RESUMEN

SIGNIFICANCE STATEMENT: Emerging evidence suggests that melanocortin neuropeptides-specifically adrenocorticotropic hormone-offer a novel, steroidogenic-independent therapeutic modality for membranous nephropathy (MN). The molecular mechanism underlying this beneficial effect, however, remains largely elusive. To investigate whether melanocortins modulate humoral immunity, the authors induced passive Heymann nephritis, a model of human MN, in wild-type and melanocortin 1 receptor (MC1R) knockout rats and treated them with melanocortin agents. Additional rats received adoptive transfer of bone marrow-derived cells beforehand from wild-type or MC1R knockout rats. The findings indicate that MC1R signaling plays a key role in negative modulation of B-cell activation and thereby suppresses humoral immune responses in passive Heymann nephritis, and suggest that MC1R signaling might offer a novel B cell-targeted therapeutic strategy for MN. BACKGROUND: Emerging evidence suggests that the pituitary neuropeptide melanocortins-specifically, adrenocorticotropic hormone-offer a novel nonsteroidogenic therapeutic modality for membranous nephropathy (MN). However, the mechanism(s) of action remains elusive. METHODS: To investigate whether melanocortins modulate humoral immunity, we induced passive Heymann nephritis (PHN), a model of MN, in wild-type (WT) and melanocortin 1 receptor (MC1R) knockout (KO) rats. We treated the animals with melanocortin agents-repository corticotropin injection, the nonsteroidogenic pan-melanocortin receptor agonist [Nle 4 , DPhe 7 ]-α-melanocyte stimulating hormone, the selective MC1R agonist MS05, vehicle gel, or phosphate-buffered saline-and evaluated kidney function, histology, and molecular changes. Additional rats received adoptive transfer of syngeneic bone marrow-derived cells beforehand from WT or MC1R KO rats. RESULTS: KO of MC1R worsened PHN and this was associated with increased deposition of autologous immunoglobulin G (IgG) and complement C5b-9 in glomeruli and higher circulating levels of autologous IgG-evidence of a sensitized humoral immune response. Melanocortin therapy ameliorated PHN in WT rats, coinciding with reduced glomerular deposition of autologous IgG and C5b -9. The beneficial efficacy of melanocortins was blunted in KO rats but restored by adoptive transfer of syngeneic bone marrow-derived cells derived from WT rats. Mechanistically, MC1R was expressed in B lymphocytes and was negatively associated with B cell activation. MC1R agonism triggered the expression of microphthalmia-associated transcription factor in activated B cells in a cAMP-dependent mode and also repressed the expression of interferon regulatory factor 4 (a lymphoid transcription factor essential for B-cell development and maturation), resulting in suppressed plasma cell differentiation and IgG production. CONCLUSIONS: MC1R signaling negatively modulates B cell activation and suppresses humoral immune responses in PHN, suggesting that MC1R signaling might offer a novel therapeutic target for MN.


Asunto(s)
Glomerulonefritis Membranosa , Animales , Ratas , Hormona Adrenocorticotrópica , alfa-MSH/farmacología , Complejo de Ataque a Membrana del Sistema Complemento , Inmunoglobulina G , Melanocortinas , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/metabolismo
3.
Clin Sci (Lond) ; 134(7): 695-710, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32167144

RESUMEN

The clinical effectiveness of adrenocorticotropin in inducing remission of steroid-resistant nephrotic syndrome points to a steroidogenic-independent anti-proteinuric activity of melanocortins. However, which melanocortin receptors (MCR) convey this beneficial effect and if systemic or podocyte-specific mechanisms are involved remain uncertain. In vivo, wild-type (WT) mice developed heavy proteinuria and kidney dysfunction following Adriamycin insult, concomitant with focal segmental glomerulosclerosis (FSGS) and podocytopathy, marked by loss of podocin and synaptopodin, podocytopenia and extensive foot process effacement on electron microscopy. All these pathologic findings were prominently attenuated by NDP-MSH, a potent non-steroidogenic pan-MCR agonist. Surprisingly, MC1R deficiency in MC1R-null mice barely affected the severity of Adriamycin-elicited injury. Moreover, the beneficial effect of NDP-MSH was completely preserved in MC1R-null mice, suggesting that MC1R is likely non-essential for the protective action. A direct podocyte effect seems to contribute to the beneficial effect of NDP-MSH, because Adriamycin-inflicted cytopathic signs in primary podocytes prepared from WT mice were all mitigated by NDP-MSH, including apoptosis, loss of podocyte markers, de novo expression of the podocyte injury marker desmin, actin cytoskeleton derangement and podocyte hypermotility. Consistent with in vivo findings, the podoprotective activity of NDP-MSH was fully preserved in MC1R-null podocytes. Mechanistically, MC1R expression was predominantly distributed to glomerular endothelial cells in glomeruli but negligibly noted in podocytes in vivo and in vitro, suggesting that MC1R signaling is unlikely involved in direct podocyte protection. Ergo, melanocortin therapy protects against podocyte injury and ameliorates proteinuria and glomerulopathy in experimental FSGS, at least in part, via a podocyte-specific non-MC1R-mediated melanocortinergic signaling.


Asunto(s)
Albuminuria/prevención & control , Apoptosis/efectos de los fármacos , Glomeruloesclerosis Focal y Segmentaria/prevención & control , Podocitos/efectos de los fármacos , Receptor de Melanocortina Tipo 1/agonistas , alfa-MSH/análogos & derivados , Albuminuria/inducido químicamente , Albuminuria/metabolismo , Albuminuria/patología , Animales , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Doxorrubicina , Glomeruloesclerosis Focal y Segmentaria/inducido químicamente , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Glomeruloesclerosis Focal y Segmentaria/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Permeabilidad , Podocitos/metabolismo , Podocitos/ultraestructura , Receptor de Melanocortina Tipo 1/genética , Receptor de Melanocortina Tipo 1/metabolismo , Transducción de Señal , alfa-MSH/farmacología
4.
J Hepatol ; 71(2): 422-433, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31102718

RESUMEN

Porphyrias are rare inherited disorders caused by specific enzyme dysfunctions in the haem synthesis pathway, which result in abnormal accumulation of specific pathway intermediates. The symptoms depend upon the chemical characteristics of these substances. Porphyrins are photoreactive and cause photocutaneous lesions on sunlight-exposed areas, whereas accumulation of porphyrin precursors is related to acute neurovisceral attacks. Current therapies are suboptimal and mostly address symptoms rather than underlying disease mechanisms. Advances in the understanding of the molecular bases and pathogenesis of porphyrias have paved the way for the development of new therapeutic strategies. In this Clinical Trial Watch we summarise the basic principles of these emerging approaches and what is currently known about their application to porphyrias of hepatic origin or with hepatic involvement.


Asunto(s)
Acetilgalactosamina/análogos & derivados , Trasplante de Médula Ósea/métodos , Resina de Colestiramina/uso terapéutico , Terapia Genética/métodos , Trasplante de Hígado/métodos , Porfirias Hepáticas/tratamiento farmacológico , Porfirias Hepáticas/cirugía , Pirrolidinas/uso terapéutico , Receptor de Melanocortina Tipo 1/agonistas , alfa-MSH/análogos & derivados , 5-Aminolevulinato Sintetasa/antagonistas & inhibidores , Acetilgalactosamina/farmacología , Acetilgalactosamina/uso terapéutico , Hemo/biosíntesis , Humanos , Hígado/metabolismo , Porfirias Hepáticas/clasificación , Porfirias Hepáticas/patología , Porfirinas/metabolismo , Pirrolidinas/farmacología , alfa-MSH/uso terapéutico
5.
Int J Mol Sci ; 20(24)2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31817532

RESUMEN

One of the first lines of cutaneous defense against photoaging is a) the synthesis of melanin and b) the initiation of an oxidative stress response to protect skin against the harmful effects of solar radiation. Safe and selective means to stimulate epidermal pigmentation associated with oxidative stress defense are; however, scarce. Activation of the melanocortin-1 receptor (MC1R) on epidermal melanocytes represents a key step in cutaneous pigmentation initiation and, additionally, it regulates cellular defense mechanisms like oxidative stress and DNA-repair. Thus, making the activation of MC1R an attractive strategy for modulating skin pigmentation and oxidative stress. In this context, we designed and synthesized pentapeptides that act as MC1R agonists. These peptides bound, with high potency, to MC1R and activated cAMP synthesis in CHO cells expressing human MC1R. Using one lead pentapeptide, we could show that this activation of MC1R was specific as testing the activation of other G-protein coupled receptors, including the MC-receptor family, was negative. In vitro efficacy on mouse melanoma cells showed similar potency as for the synthetic MC1R agonist alpha-melanocyte stimulating hormone (NDP-alpha-MSH). Moreover, we could reproduce this activity in human skin tissue culture. The lead pentapeptide was able to induce ex-vivo protein expression of key melanogenesis markers melanocyte inducing transcription factor (MITF), tyrosinase (TYR), and tyrosinase-related protein 1 (TYRP-1). Concerning oxidative stress response, we found that the pentapeptide enhanced the activation of Nrf2 after UVA-irradiation. Our results make this pentapeptide an ideal candidate as a skin pigmentation enhancer that mimics alpha-MSH and may also have anti-photoaging effects on the skin.


Asunto(s)
Descubrimiento de Drogas , Melanocitos/metabolismo , Oligopéptidos , Receptor de Melanocortina Tipo 1/agonistas , Envejecimiento de la Piel/efectos de los fármacos , Pigmentación de la Piel/efectos de los fármacos , Adulto , Animales , Células CHO , Cricetulus , Femenino , Humanos , Glicoproteínas de Membrana/metabolismo , Ratones , Factor de Transcripción Asociado a Microftalmía/metabolismo , Monofenol Monooxigenasa/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Oligopéptidos/química , Oligopéptidos/farmacología , Oxidorreductasas/metabolismo , Receptor de Melanocortina Tipo 1/metabolismo , Envejecimiento de la Piel/efectos de la radiación , Pigmentación de la Piel/efectos de la radiación , Rayos Ultravioleta
6.
Circulation ; 136(1): 83-97, 2017 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-28450348

RESUMEN

BACKGROUND: The melanocortin 1 receptor (MC1-R) is expressed by monocytes and macrophages, where it exerts anti-inflammatory actions on stimulation with its natural ligand α-melanocyte-stimulating hormone. The present study was designed to investigate the specific role of MC1-R in the context of atherosclerosis and possible regulatory pathways of MC1-R beyond anti-inflammation. METHODS: Human and mouse atherosclerotic samples and primary mouse macrophages were used to study the regulatory functions of MC1-R. The impact of pharmacological MC1-R activation on atherosclerosis was assessed in apolipoprotein E-deficient mice. RESULTS: Characterization of human and mouse atherosclerotic plaques revealed that MC1-R expression localizes in lesional macrophages and is significantly associated with the ATP-binding cassette transporters ABCA1 and ABCG1, which are responsible for initiating reverse cholesterol transport. Using bone marrow-derived macrophages, we observed that α-melanocyte-stimulating hormone and selective MC1-R agonists similarly promoted cholesterol efflux, which is a counterregulatory mechanism against foam cell formation. Mechanistically, MC1-R activation upregulated the levels of ABCA1 and ABCG1. These effects were accompanied by a reduction in cell surface CD36 expression and in cholesterol uptake, further protecting macrophages from excessive lipid accumulation. Conversely, macrophages deficient in functional MC1-R displayed a phenotype with impaired efflux and enhanced uptake of cholesterol. Pharmacological targeting of MC1-R in atherosclerotic apolipoprotein E-deficient mice reduced plasma cholesterol levels and aortic CD36 expression and increased plaque ABCG1 expression and signs of plaque stability. CONCLUSIONS: Our findings identify a novel role for MC1-R in macrophage cholesterol transport. Activation of MC1-R confers protection against macrophage foam cell formation through a dual mechanism: It prevents cholesterol uptake while concomitantly promoting ABCA1- and ABCG1-mediated reverse cholesterol transport.


Asunto(s)
Colesterol/metabolismo , Macrófagos/metabolismo , Receptor de Melanocortina Tipo 1/metabolismo , Transducción de Señal/fisiología , Animales , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Femenino , Células Espumosas/efectos de los fármacos , Células Espumosas/metabolismo , Células HEK293 , Humanos , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Distribución Aleatoria , Receptor de Melanocortina Tipo 1/agonistas , Transducción de Señal/efectos de los fármacos , alfa-MSH/metabolismo , alfa-MSH/farmacología
7.
J Immunol ; 194(7): 3381-8, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25725103

RESUMEN

There is a need for novel approaches to control pathologies with overexuberant inflammatory reactions. Targeting melanocortin (MC) receptors represents a promising therapy for obesity and chronic inflammation, but lack of selectivity and safety concerns limit development. A new way to increase selectivity of biological effects entails the identification of biased agonists. In this study, we characterize the small molecule AP1189 as a biased agonist at receptors MC1 and MC3. Although not provoking canonical cAMP generation, AP1189 addition to MC1 or MC3, but not empty vector, transfected HEK293 cells caused ERK1/2 phosphorylation, a signaling responsible for the proefferocytic effect evoked in mouse primary macrophages. Added to macrophage cultures, AP1189 reduced cytokine release, an effect reliant on both MC1 and MC3 as evident from the use of Mc1r(-/-) and Mc3r(-/-) macrophages. No melanogenesis was induced by AP1189 in B16-F10 melanocytes. In vivo, oral AP1189 elicited anti-inflammatory actions in peritonitis and, upon administration at the peak of inflammation, accelerated the resolution phase by ∼3-fold. Finally, given the clinical efficacy of adrenocorticotropin in joint diseases, AP1189 was tested in experimental inflammatory arthritis, where this biased agonist afforded significant reduction of macroscopic and histological parameters of joint disruption. These proof-of-concept analyses with AP1189, an active oral anti-inflammatory and resolution-promoting compound, indicate that biased agonism at MC receptors is an innovative, viable approach to yield novel anti-inflammatory molecules endowed with a more favorable safety profile.


Asunto(s)
Guanidinas/farmacología , Pirroles/farmacología , Receptores de Melanocortina/agonistas , Receptores de Melanocortina/metabolismo , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/genética , Artritis Experimental/metabolismo , Artritis Experimental/patología , Calcio/metabolismo , Modelos Animales de Enfermedad , Técnicas de Inactivación de Genes , Guanidinas/administración & dosificación , Células HEK293 , Humanos , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/metabolismo , Masculino , Melaninas/metabolismo , Melanoma Experimental , Ratones , Neutrófilos/inmunología , Neutrófilos/metabolismo , Peritonitis/inducido químicamente , Peritonitis/tratamiento farmacológico , Peritonitis/genética , Peritonitis/metabolismo , Peritonitis/patología , Fagocitosis/inmunología , Pirroles/administración & dosificación , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/genética , Receptor de Melanocortina Tipo 1/metabolismo , Receptor de Melanocortina Tipo 3/agonistas , Receptor de Melanocortina Tipo 3/genética , Receptor de Melanocortina Tipo 3/metabolismo , Receptores de Melanocortina/genética , Transducción de Señal/efectos de los fármacos
8.
Am J Physiol Renal Physiol ; 310(9): F846-56, 2016 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-26887829

RESUMEN

Drugs containing adrenocorticotropic hormone have been used as therapy for patients with nephrotic syndrome. We have previously shown that adrenocorticotropic hormone and a selective agonist for the melanocortin 1 receptor (MC1R) exert beneficial actions in experimental membranous nephropathy with reduced proteinuria, reduced oxidative stress, and improved glomerular morphology and function. Our hypothesis is that MC1R activation in podocytes elicits beneficial effects by promoting stress fibers and maintaining podocyte viability. To test the hypothesis, we cultured podocytes and used highly specific agonists for MC1R. Podocytes were subjected to the nephrotic-inducing agent puromycin aminonucleoside, and downstream effects of MC1R activation on podocyte survival, antioxidant defense, and cytoskeleton dynamics were studied. To increase the response and enhance intracellular signals, podocytes were transduced to overexpress MC1R. We showed that puromycin promotes MC1R expression in podocytes and that activation of MC1R promotes an increase of catalase activity and reduces oxidative stress, which results in the dephosphorylation of p190RhoGAP and formation of stress fibers through RhoA. In addition, MC1R agonists protect against apoptosis. Together, these mechanisms protect the podocyte against puromycin. Our findings strongly support the hypothesis that selective MC1R-activating agonists protect podocytes and may therefore be useful to treat patients with nephrotic syndromes commonly considered as podocytopathies.


Asunto(s)
Catalasa/metabolismo , Podocitos/efectos de los fármacos , Receptor de Melanocortina Tipo 1/agonistas , Proteína de Unión al GTP rhoA/metabolismo , Animales , Antimetabolitos , Células Cultivadas , Activación Enzimática , Ratones , Nefrosis/inducido químicamente , Nefrosis/metabolismo , Estrés Oxidativo/efectos de los fármacos , Puromicina Aminonucleósido , Especies Reactivas de Oxígeno/metabolismo , Receptor de Melanocortina Tipo 1/genética , Fibras de Estrés/efectos de los fármacos
9.
Bioorg Med Chem Lett ; 25(22): 5306-8, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26433448

RESUMEN

The melanocortin system consists of five receptor subtypes (MC1-5R), endogenous agonists derived from the proopiomelanocortin gene transcript, and the antagonists agouti and agouti-related protein. The Escherichia coli heat shock protein ClpB has previously been described as an antigen mimetic to the endogenous melanocortin agonist α-MSH. Herein, we investigated if a fragment of the ClpB protein could directly signal through the melanocortin receptors. We synthesized a complementary fragment of the ClpB protein that partially aligned with α-MSH. Pharmacological assessment of this fragment resulted in no antagonist activity at the MC3R or the MC4R and no agonist activity at the MC4R. Partial receptor activation was observed for the MC3R and MC5R at 100 µM concentrations. This fragment was shown to be a full micromolar MC1R agonist and may serve as a template for future research into selective MC1R ligands.


Asunto(s)
Proteínas de Escherichia coli/farmacología , Proteínas de Choque Térmico/farmacología , Fragmentos de Péptidos/farmacología , Receptor de Melanocortina Tipo 1/agonistas , Secuencia de Aminoácidos , Animales , Endopeptidasa Clp , Escherichia coli , Proteínas de Escherichia coli/síntesis química , Células HEK293 , Proteínas de Choque Térmico/síntesis química , Humanos , Ligandos , Ratones , Fragmentos de Péptidos/síntesis química
10.
Clin Pharmacol Drug Dev ; 13(7): 729-738, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38746989

RESUMEN

Dersimelagon is an orally administered selective melanocortin-1 receptor agonist being investigated for treatment of erythropoietic protoporphyria, X-linked protoporphyria, and diffuse cutaneous systemic sclerosis. Dersimelagon is extensively metabolized in the liver, and potential recipients may have liver dysfunction. Further, effects of renal impairment on pharmacokinetic properties should be established in drugs intended for chronic use. Two separate studies (ClinicalTrials.gov: NCT04116476; NCT04656795) evaluated the effects of hepatic and renal impairment on dersimelagon pharmacokinetics, safety, and tolerability. Participants with mild (n = 7) or moderate (n = 8) hepatic impairment or normal hepatic function (n = 8) received a single oral 100-mg dersimelagon dose. Participants with mild (n = 8), moderate (n = 8), or severe (n = 8) renal impairment or normal renal function (n = 8) received a single 300-mg dose. Systemic exposure to dersimelagon was comparable with mild hepatic impairment but higher with moderate hepatic impairment (maximum observed plasma concentration, 1.56-fold higher; area under the plasma concentration-time curve from time 0 extrapolated to infinity, 1.70-fold higher) compared with normal hepatic function. Maximum observed plasma concentration and area under the plasma concentration-time curve from time 0 extrapolated to infinity were similar with moderate renal impairment but higher with mild (1.86- and 1.87-fold higher, respectively) and severe (1.17- and 1.45-fold higher, respectively) renal impairment versus normal renal function. Dersimelagon was generally well tolerated.


Asunto(s)
Receptor de Melanocortina Tipo 1 , Humanos , Masculino , Femenino , Persona de Mediana Edad , Adulto , Administración Oral , Receptor de Melanocortina Tipo 1/metabolismo , Receptor de Melanocortina Tipo 1/agonistas , Anciano , Hepatopatías/metabolismo , Área Bajo la Curva , Insuficiencia Renal/metabolismo , Adulto Joven , alfa-MSH/análogos & derivados , alfa-MSH/farmacocinética , alfa-MSH/administración & dosificación , alfa-MSH/efectos adversos , alfa-MSH/farmacología , Índice de Severidad de la Enfermedad
11.
Kidney Int ; 83(4): 635-46, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23325074

RESUMEN

Adrenocorticotropic hormone (ACTH) has a renoprotective effect in chronic kidney disease; however, its effect on acute kidney injury (AKI) remains unknown. In a rat model of tumor necrosis factor (TNF)-induced AKI, we found that ACTH gel prevented kidney injury, corrected acute renal dysfunction, and improved survival. Morphologically, ACTH gel ameliorated TNF-induced acute tubular necrosis, associated with a reduction in tubular apoptosis. While the steroidogenic response to ACTH gel plateaued, the kidney-protective effect continued to increase at even higher doses, suggesting steroid-independent mechanisms. Of note, ACTH also acts as a key agonist of the melanocortin system, with its cognate melanocortin 1 receptor (MC1R) abundantly expressed in renal tubules. In TNF-injured tubular epithelial cells in vitro, ACTH reinstated cellular viability and eliminated apoptosis. This beneficial effect was blunted in MC1R-silenced cells, suggesting that this receptor mediates the anti-apoptotic signaling of ACTH. Moreover, ACTH gel protected mice against cecal ligation puncture-induced septic AKI better than α-melanocyte-stimulating hormone: a protein equal in biological activity to ACTH except for steroidogenesis. Thus, ACTH has additive renoprotective actions achieved by both steroid-dependent mechanisms and MC1R-directed anti-apoptosis. ACTH may represent a novel therapeutic strategy to prevent or treat AKI.


Asunto(s)
Lesión Renal Aguda/prevención & control , Hormona Adrenocorticotrópica/farmacología , Corticosterona/sangre , Riñón/efectos de los fármacos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/microbiología , Lesión Renal Aguda/patología , Lesión Renal Aguda/fisiopatología , Albuminuria/metabolismo , Albuminuria/prevención & control , Animales , Apoptosis/efectos de los fármacos , Ciego/microbiología , Ciego/cirugía , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citoprotección , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Geles , Tasa de Filtración Glomerular/efectos de los fármacos , Riñón/metabolismo , Riñón/microbiología , Riñón/patología , Riñón/fisiopatología , Necrosis Tubular Aguda/metabolismo , Necrosis Tubular Aguda/patología , Necrosis Tubular Aguda/prevención & control , Túbulos Renales/efectos de los fármacos , Túbulos Renales/metabolismo , Túbulos Renales/patología , Ligadura , Masculino , Ratones , Punciones , Interferencia de ARN , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/genética , Receptor de Melanocortina Tipo 1/metabolismo , Factores de Tiempo , Transfección , Factor de Necrosis Tumoral alfa , Regulación hacia Arriba
12.
Pharmacol Res Perspect ; 11(3): e01084, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37078227

RESUMEN

Dersimelagon (formerly MT-7117) is a novel, orally administered nonpeptide small molecule selective agonist for melanocortin 1 receptor currently being investigated for the treatment of erythropoietic protoporphyria, X-linked protoporphyria, and diffuse cutaneous systemic sclerosis (dcSSc). Findings of studies evaluating the absorption, distribution, metabolism, and excretion (ADME) of dersimelagon following a single dose of [14 C]dersimelagon in healthy adult volunteers (N = 6) who participated in phase 1, single-center, open-label, mass balance study (NCT03503266), and in preclinical animal models are presented. Rapid absorption and elimination were observed following oral administration of [14 C]dersimelagon in clinical and nonclinical studies, with a mean Tmax of 30 min in rats and 1.5 h in monkeys, and a median Tmax of 2 h in humans. In rats, there was a widespread distribution of [14 C]dersimelagon-related material, but little or no radioactivity was detected in the brain or fetal tissues. In humans, elimination of radioactivity in urine was negligible (excretion of radioactivity into the urine: 0.31% of dose), and the primary route of excretion was feces, with more than 90% of the radioactivity recovered through 5 days postdose. Based on these findings, dersimelagon is not retained in the human body. Findings from humans and animals suggest dersimelagon is extensively metabolized to the glucuronide in the liver, which is eliminated in bile, and hydrolyzed to unchanged dersimelagon in the gut. The results to date for this orally administered agent elucidate the ADME of dersimelagon in human and animal species and support its continued development for the treatment of photosensitive porphyrias and dcSSc.


Asunto(s)
Bilis , Receptor de Melanocortina Tipo 1 , Adulto , Animales , Humanos , Ratas , Bilis/química , Heces/química , Voluntarios Sanos , Hígado , Receptor de Melanocortina Tipo 1/agonistas
13.
Anesthesiology ; 116(3): 692-700, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22266570

RESUMEN

BACKGROUND: Melanocortin peptides improve hemodynamic parameters and prevent death during severe hemorrhagic shock. In the present research we determined influences of a synthetic melanocortin 1/4 receptor agonist on the molecular changes that occur in rat liver during hemorrhage. METHODS: Controlled-volume hemorrhage was performed in adult rats under general anesthesia by a stepwise blood withdrawal until mean arterial pressure fell to 40 mmHg. Then rats received either saline or the synthetic melanocortin 1/4 receptor agonist Butir-His-D-Phe-Arg-Trp-Sar-NH2 (Ro27-3225; n = 6-8 per group). Hemogasanalysis was performed throughout a 60-min period. Gene expression in liver samples was determined at 1 or 3 h using quantitative real-time polymerase chain reaction. RESULTS: At 1 h, in saline-treated shocked rats, there were significant increases in activating transcription factor 3 (Atf3), early growth response 1 (Egr1), heme oxygenase (decycling) 1 (Hmox1), FBJ murine osteosarcoma viral oncogene homolog (Fos), and jun oncogene (Jun). These changes were prevented by Ro27-3225 (mean ± SEM: Atf3 152.83 ± 58.62 vs. 579.00 ± 124.13, P = 0.002; Egr1 13.21 ± 1.28 vs. 26.63 ± 1.02, P = 0.001; Hmox1 3.28 ± 0.31 vs. 166.54 ± 35.03, P = 0.002; Fos 4.36 ± 1.03 vs. 14.90 ± 3.44, P < 0.001; Jun 6.62 ± 1.93 vs. 15.07 ± 2.09, P = 0.005; respectively). Increases in alpha-2-macroglobulin (A2m), heat shock 70kD protein 1A (Hspa1a), erythropoietin (Epo), and interleukin-6 (Il6) occurred at 3 h in shocked rats and were prevented by Ro27-3225 treatment (A2m 6.90 ± 0.82 vs. 36.73 ± 4.00, P < 0.001; Hspa1a 10.34 ± 3.28 vs. 25.72 ± 3.64, P = 0.001; Epo 0.49 ± 0.13 vs. 2.37 ± 0.73, P = 0.002; Il6 1.05 ± 0.15 vs. 1.88 ± 0.23, P < 0.001; respectively). Further, at 3 h in shocked rats treated with Ro27-3225 there were significant increases in tight junction protein 1 (Tjp1; 27.30 ± 2.43 vs. 5.03 ± 1.68, P < 0.001) and nuclear receptor subfamily 4, group A, member 1 (Nr4a1; 91.03 ± 16.20 vs. 30.43 ± 11.0, P = 0.01) relative to sham animals. Treatment with Ro27-3225 rapidly restored blood pressure, hemogasanalysis parameters, and lactate blood levels. CONCLUSIONS: Melanocortin treatment significantly prevents most of the systemic and hepatic detrimental changes induced by hemorrhage.


Asunto(s)
Melanocortinas/uso terapéutico , Péptidos/uso terapéutico , Choque Hemorrágico/tratamiento farmacológico , Choque Hemorrágico/metabolismo , Animales , Melanocortinas/metabolismo , Péptidos/metabolismo , Ratas , Ratas Wistar , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/fisiología , Receptor de Melanocortina Tipo 4/agonistas , Receptor de Melanocortina Tipo 4/fisiología , Choque Hemorrágico/genética , Resultado del Tratamiento
14.
J Med Chem ; 65(19): 12956-12969, 2022 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-36167503

RESUMEN

In this work, cysteine staples were used as a late-stage functionalization strategy to diversify peptides and build conjugates targeting the melanocortin G-protein-coupled receptors [melanocortin receptor-1 (MC1R) and MC3R-MC5R]. Monocyclic and bicyclic agonists based on sunflower trypsin inhibitor-1 were used to generate a selection of stapled peptides that were evaluated for binding (pKi) and functional activation (pEC50) of the melanocortin receptor subtypes. Stapled peptides generally had improved activity, with aromatic stapled peptides yielding selective MC1R agonists, including a xylene-stapled peptide (2) with an EC50 of 1.9 nM for MC1R and >150-fold selectivity for MC3R and MC4R. Selected stapled peptides were further functionalized with linkers and payloads, generating a series of conjugated peptides with potent MC1R activity, including one pyridazine-functionalized peptide (21) with picomolar activity at MC1R (Ki 58 pM; EC50 < 9 pM). This work demonstrates that staples can be used as modular synthetic tools to tune potency and selectivity in peptide-based drug design.


Asunto(s)
Piridazinas , Receptor de Melanocortina Tipo 1 , Cisteína , Melanocortinas , Péptidos/farmacología , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 3 , Receptor de Melanocortina Tipo 4 , Receptores de Melanocortina/metabolismo , Relación Estructura-Actividad , Xilenos
15.
J Invest Dermatol ; 142(2): 293-302.e1, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34362555

RESUMEN

The G protein-coupled MC1R is expressed in melanocytes and has a pivotal role in human skin pigmentation, with reduced function in human genetic variants exhibiting a red hair phenotype and increased melanoma predisposition. Beyond its role in pigmentation, MC1R is increasingly recognized as promoting UV-induced DNA damage repair. Consequently, there is mounting interest in targeting MC1R for therapeutic benefit. However, whether MC1R expression is restricted to melanocytes or is more widely expressed remains a matter of debate. In this paper, we review MC1R function and highlight that unbiased analysis suggests that its expression is restricted to melanocytes, granulocytes, and the brain.


Asunto(s)
Melanoma/genética , Receptor de Melanocortina Tipo 1/metabolismo , Neoplasias Cutáneas/genética , Animales , Encéfalo/metabolismo , Daño del ADN/efectos de la radiación , Reparación del ADN , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Variación Genética , Granulocitos/metabolismo , Color del Cabello , Humanos , Lipoilación/efectos de los fármacos , Mutación con Pérdida de Función , Melaninas/metabolismo , Melanocitos/metabolismo , Melanoma/patología , Ratones , Terapia Molecular Dirigida/métodos , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/genética , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Pigmentación de la Piel , Rayos Ultravioleta/efectos adversos
16.
Oxid Med Cell Longev ; 2022: 4054938, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35140838

RESUMEN

Neuronal apoptosis induced by oxidative stress plays an important role in the pathogenesis and progression of hypoxic-ischemic encephalopathy (HIE). Previous studies reported that activation of melanocortin-1 receptor (MC1R) exerts antioxidative stress, antiapoptotic, and neuroprotective effects in various neurological diseases. However, whether MC1R activation can attenuate oxidative stress and neuronal apoptosis after hypoxic-ischemic- (HI-) induced brain injury remains unknown. Herein, we have investigated the role of MC1R activation with BMS-470539 in attenuating oxidative stress and neuronal apoptosis induced by HI and the underlying mechanisms. 159 ten-day-old unsexed Sprague-Dawley rat pups were used. HI was induced by right common carotid artery ligation followed by 2.5 h of hypoxia. The novel-selective MC1R agonist BMS-470539 was administered intranasally at 1 h after HI induction. MC1R CRISPR KO plasmid and Nurr1 CRISPR KO plasmid were administered intracerebroventricularly at 48 h before HI induction. Percent brain infarct area, short-term neurobehavioral tests, Western blot, immunofluorescence staining, Fluoro-Jade C staining, and MitoSox Staining were performed. We found that the expression of MC1R and Nurr1 increased, peaking at 48 h post-HI. MC1R and Nurr1 were expressed on neurons at 48 h post-HI. BMS-470539 administration significantly attenuated short-term neurological deficits and infarct area, accompanied by a reduction in cleaved caspase-3-positive neurons at 48 h post-HI. Moreover, BMS-470539 administration significantly upregulated the expression of MC1R, cAMP, p-PKA, Nurr1, HO-1, and Bcl-2. However, it downregulated the expression of 4-HNE and Bax, as well as reduced FJC-positive cells, MitoSox-positive cells, and 8-OHdG-positive cells at 48 h post-HI. MC1R CRISPR and Nurr1 CRISPR abolished the antioxidative stress, antiapoptotic, and neuroprotective effects of BMS-470539. In conclusion, our findings demonstrated that BMS-470539 administration attenuated oxidative stress and neuronal apoptosis and improved neurological deficits in a neonatal HI rat model, partially via the MC1R/cAMP/PKA/Nurr1 signaling pathway. Early administration of BMS-470539 may be a novel therapeutic strategy for infants with HIE.


Asunto(s)
Antioxidantes/administración & dosificación , Apoptosis/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/metabolismo , Imidazoles/administración & dosificación , Neuronas/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Estrés Oxidativo/efectos de los fármacos , Receptor de Melanocortina Tipo 1/metabolismo , Transducción de Señal/efectos de los fármacos , Administración Intranasal , Animales , Animales Recién Nacidos , Femenino , Técnicas de Inactivación de Genes/métodos , Masculino , Neuronas/efectos de los fármacos , Miembro 2 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Ratas , Ratas Sprague-Dawley , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 1/genética , Transducción de Señal/genética , Resultado del Tratamiento
17.
Bioorg Med Chem Lett ; 21(5): 1459-63, 2011 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-21277204

RESUMEN

A new class of melanocortin 4 receptor (MC4r) agonists was discovered from an unexpected sidereaction in which formaldehyde caused cyclization. These cyclophanes were found to be sub micromolar agonists of the MC1 and MC4 and were less potent on the MC3 and MC5 receptor. They were shown to compete with the peptidic antagonist SHU9119 for binding to the MC4 receptor. In an acute feeding study in Sprague Dawley rats, food intake was reduced more than 50% versus vehicle after 3 h at a dose of 1 mg/kg.


Asunto(s)
Éteres Cíclicos/síntesis química , Piperidinas/síntesis química , Receptor de Melanocortina Tipo 1/agonistas , Receptor de Melanocortina Tipo 4/agonistas , Animales , Éteres Cíclicos/farmacología , Masculino , Estructura Molecular , Piperidinas/farmacología , Unión Proteica , Ratas , Ratas Sprague-Dawley
18.
J Am Soc Nephrol ; 21(8): 1290-8, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20507942

RESUMEN

Membranous nephropathy is one of the most common causes of nephrotic syndrome in adults. Recent reports suggest that treatment with adrenocorticotropic hormone (ACTH) reduces proteinuria, but the mechanism of action is unknown. Here, we identified gene expression of the melanocortin receptor MC1R in podocytes, glomerular endothelial cells, mesangial cells, and tubular epithelial cells. Podocytes expressed most MC1R protein, which colocalized with synaptopodin but not with an endothelial-specific lectin. We treated rats with passive Heymann nephritis (PHN) with MS05, a specific MC1R agonist, which significantly reduced proteinuria compared with untreated PHN rats (P < 0.01). Furthermore, treatment with MC1R agonists improved podocyte morphology and reduced oxidative stress. In summary, podocytes express MC1R, and MC1R agonism reduces proteinuria, improves glomerular morphology, and reduces oxidative stress in nephrotic rats with PHN. These data may explain the proteinuria-reducing effects of ACTH observed in patients with membranous nephropathy, and MC1R agonists may provide a new therapeutic option for these patients.


Asunto(s)
Hormona Adrenocorticotrópica/uso terapéutico , Hormonas/uso terapéutico , Proteinuria/prevención & control , Receptor de Melanocortina Tipo 1/agonistas , Adulto , Anciano , Animales , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Femenino , Glomerulonefritis Membranosa/complicaciones , Humanos , Masculino , Células Mesangiales/metabolismo , Persona de Mediana Edad , Podocitos/metabolismo , Proteinuria/etiología , Ratas , Receptor de Melanocortina Tipo 1/biosíntesis , Urotelio/citología , Urotelio/metabolismo
19.
J Med Chem ; 64(14): 9906-9915, 2021 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-34197114

RESUMEN

We have designed a new class of highly potent bivalent melanocortin receptor ligands based on the nature-derived bicyclic peptide sunflower trypsin inhibitor 1 (SFTI-1). Incorporation of melanotropin pharmacophores in each of the two turn regions of SFTI-1 resulted in substantial gains in agonist activity particularly at human melanocortin receptors 1 and 3 (hMC1R/hMC3R) compared to monovalent analogues. In in vitro binding and functional assays, the most potent molecule, compound 6, displayed low picomolar agonist activity at hMC1R (pEC50 > 10.3; EC50 < 50 pM; pKi: 10.16 ± 0.04; Ki: 69 ± 5 pM) and is at least 30-fold more selective for this receptor than for hMC3R, hMC4R, or hMC5R. The results are discussed in the context of structural homology models of hMCRs in complex with the developed bivalent ligands.


Asunto(s)
Péptidos Cíclicos/farmacología , Receptor de Melanocortina Tipo 1/agonistas , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/química , Relación Estructura-Actividad
20.
J Invest Dermatol ; 141(7): 1819-1829, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33609553

RESUMEN

Activation of the human melanocortin 1 receptor (hMC1R) expressed on melanocytes by α-melanocortin plays a central role in regulating human pigmentation and reducing the genotoxicity of UV by activating DNA repair and antioxidant defenses. For the development of a hMC1R-targeted photoprotection strategy, we designed tetra- and tripeptide agonists with modifications that provide the necessary lipophilicity and hMC1R selectivity to be effective drugs. These peptides proved to be superior to most of the existing analogs of the physiological tridecapeptide α-melanocortin because of their small size and high hMC1R selectivity. Testing on primary cultures of human melanocytes showed that these peptides are highly potent with prolonged stimulation of melanogenesis, enhanced repair of UV-induced DNA photoproducts, and reduced apoptosis. One of the tripeptides, designated as LK-514 (5), with a molecular weight of 660 Da, has unprecedented (>100,000) hMC1R selectivity when compared with the other melanocortin receptors hMC3R, hMC4R, and hMC5R, and increases pigmentation (sunless tanning) in a cultured, three-dimensional skin model. These new analogs should be efficacious in preventing skin cancer, including melanoma, and treatment of skin disorders, such as vitiligo and polymorphic light eruptions.


Asunto(s)
Daño del ADN/efectos de los fármacos , Fármacos Dermatológicos/farmacología , Receptor de Melanocortina Tipo 1/agonistas , Pigmentación de la Piel/efectos de los fármacos , Rayos Ultravioleta/efectos adversos , Células Cultivadas , Daño del ADN/efectos de la radiación , Fármacos Dermatológicos/uso terapéutico , Humanos , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Melanocitos/efectos de la radiación , Melanoma/etiología , Melanoma/prevención & control , Trastornos por Fotosensibilidad/tratamiento farmacológico , Trastornos por Fotosensibilidad/genética , Cultivo Primario de Células , Receptor de Melanocortina Tipo 1/metabolismo , Piel/efectos de los fármacos , Piel/efectos de la radiación , Enfermedades Cutáneas Genéticas/tratamiento farmacológico , Enfermedades Cutáneas Genéticas/genética , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/prevención & control , Pigmentación de la Piel/efectos de la radiación , Vitíligo/tratamiento farmacológico , Vitíligo/genética , alfa-MSH/metabolismo
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