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1.
Adv Drug Deliv Rev ; 191: 114613, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36343757

RESUMEN

Nanomedicines are used to improve the efficacy and safety of pharmacotherapeutic interventions. Unraveling the biological behavior of nanomedicines, including their biodistribution and target site accumulation, is essential to establish design criteria that contribute to superior performance. CriPec® technology is based on amphiphilic methoxy-poly(ethylene glycol)-b-poly[N-(2-hydroxypropyl) methacrylamide lactate] (mPEG-b-pHPMAmLacn) block copolymers, which are designed to upon self-assembly covalently entrap active pharmaceutical ingredients (API) in core-crosslinked polymeric micelles (CCPM). Key features of CCPM are a prolonged circulation time, high concentrations at pathological sites, and low levels of accumulation in the majority of healthy tissues. Proprietary hydrolysable linkers allow for tunable and sustained release of entrapped API, including hydrophobic and hydrophilic small molecules, as well as peptides and oligonucleotides. Preclinical imaging experiments provided valuable information on their tumor and tissue accumulation and distribution, as well as on uptake by cancer, healthy and immune cells. The frontrunner formulation CPC634, which refers to 65 nm-sized CCPM entrapping the chemotherapeutic drug docetaxel, showed excellent pharmacokinetic properties, safety, tumor accumulation and antitumor efficacy in multiple animal models. In the clinic, CPC634 also demonstrated favorable pharmacokinetics, good tolerability, signs of efficacy, and enhanced localization in tumor tissue as compared to conventional docetaxel. PET imaging of radiolabeled CPC634 showed quantifiable accumulation in âˆ¼50 % of tumors and metastases in advanced-stage cancer patients, and demonstrated potential for use in a theranostic setting even when applied at a companion diagnostic dose. Altogether, the preclinical and clinical results obtained to date demonstrate that mPEG-b-pHPMAmLacn CCPM based on CriPec® technology are a potent, tunable, broadly applicable and well-tolerable platform for targeted drug delivery and improved anticancer therapy.


Asunto(s)
Antineoplásicos , Neoplasias , Animales , Micelas , Docetaxel/farmacocinética , Distribución Tisular , Portadores de Fármacos/química , Polietilenglicoles/química , Polímeros/química , Neoplasias/tratamiento farmacológico , Antineoplásicos/uso terapéutico
2.
Biochem Pharmacol ; 85(8): 1162-70, 2013 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-23415902

RESUMEN

Follicle-stimulating hormone (FSH) activates FSH receptors (FSHR) in granulosa cells to induce follicle differentiation, growth and estradiol production. FSH is used clinically to treat female infertility and is administered by injection. To increase patient convenience and compliance, compound homogeneity and composition, low molecular weight (LMW), orally bioavailable, FSHR agonists are now being developed to replace FSH. In this study, we present the signaling mechanisms of a newly developed LMW dihydropyridine agonist of the FSHR, Org 214444-0. Org 214444-0 is shown to be a stereoselective, nanomolar potent FSHR agonist and selective over the structurally related LHR and TSHR. Org 214444-0 is an allosteric agonist interacting with the transmembrane region of the FSHR. When co-incubated with FSH, Org 214444-0 augments FSH's potency in binding (6.5-fold) and adenylyl cyclase/cAMP activation (3.5-fold) in a concentration-dependent manner. Like FSH, Org 214444-0 induces FSHR internalization and is only marginally effective in stimulating phospholipase C. Moreover, Org 214444-0 stimulates cAMP and estradiol production in human granulosa cells in culture and supports the follicular phase in mature female rats. We conclude that Org 214444-0 is a bonafide FSHR agonist.


Asunto(s)
Dihidropiridinas/farmacología , Receptores de HFE/agonistas , Sulfonamidas/farmacología , Regulación Alostérica , Secuencia de Aminoácidos , Animales , Células CHO , Cricetinae , Cricetulus , AMP Cíclico/fisiología , Femenino , Hormona Folículo Estimulante/metabolismo , Datos de Secuencia Molecular , Peso Molecular , Ratas , Receptores de HFE/química , Transducción de Señal , Fosfolipasas de Tipo C/metabolismo
3.
Eur J Pharmacol ; 651(1-3): 227-33, 2011 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-21115001

RESUMEN

Corifollitropin alfa (Elonva®, MSD, previously N.V. Organon or Schering-Plough Oss, The Netherlands) is a newly developed sustained follicle stimulant composed of the α subunit of human follicle-stimulating hormone (FSH) and a hybrid ß subunit formed by fusion of the human chorionic gonadotropin ß subunit carboxy terminal peptide with the ß subunit of human FSH. Binding characteristics of corifollitropin alfa at the rat FSH receptor and transactivation properties at the rat FSH receptor, human luteinizing hormone (LH) receptor, and human thyroid-stimulating hormone receptor (TSH receptor) were assessed in vitro. Bioactivity of corifollitropin alfa in rats was also assessed. Serum corifollitropin alfa levels in rats and dogs were used to derive the main pharmacokinetic parameters of corifollitropin alfa. Binding and transactivation profile of corifollitropin alfa to rat FSH receptor was specific and comparable to that of recombinant human FSH, with no intrinsic TSH receptor or LH receptor activation. From pharmacokinetic studies, circulating half-life of corifollitropin alfa was calculated to be 17.3h in rats and 46.9h in dogs, 1.5- to 2-fold longer than recombinant FSH. Corifollitropin alfa demonstrated a 2- to 4-fold increase in bioactivity (ovarian weight, serum estradiol and progesterone, ovulated ova) over recombinant FSH across all in vivo parameters assessed. These data demonstrate that corifollitropin alfa is a specific ligand with high affinity for FSH receptor, lacking intrinsic activity for LH receptor and TSH receptor. By virtue of its increased in vivo half-life, corifollitropin alfa can be a valuable alternative to FSH by acting as a sustained follicle stimulant.


Asunto(s)
Descubrimiento de Drogas , Hormona Folículo Estimulante Humana/farmacología , Animales , Células CHO , Cricetinae , Cricetulus , Perros , Estradiol/sangre , Femenino , Hormona Folículo Estimulante Humana/metabolismo , Hormona Folículo Estimulante Humana/farmacocinética , Humanos , Tamaño de los Órganos/efectos de los fármacos , Ovario/anatomía & histología , Ovario/efectos de los fármacos , Progesterona/sangre , Ratas , Receptores de HFE/genética , Receptores de HFE/metabolismo , Factores de Tiempo , Activación Transcripcional/efectos de los fármacos
4.
Fertil Steril ; 92(2): 613-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18692804

RESUMEN

OBJECTIVE: To assess the glycoform distribution patterns of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) during the menstrual cycle at different ages and FSH levels, after menopause, and with premature ovarian failure (POF). DESIGN: Controlled clinical study. SETTING: Healthy volunteers in an academic research environment. PATIENT(S): Women aged 20 to 25 years with normal early follicular (EF) serum FSH (<10 IU/L), women aged 40 to 45 years with normal or increased EF serum FSH, postmenopausal women, and women with POF. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): FSH and LH glycoform distributions as assessed by chromatofocusing. RESULT(S): In both postmenopausal and in women with POF, more acidic FSH glycoforms were found compared with young cyclic premenopausal women. In women aged 40 to 45 years with normal FSH levels, these acidic glycoform profiles already showed a statistically significant difference from the younger women. This difference was to attributable to the early follicular and luteal cycle phases. Overall, during aging and after ovarian failure, FSH becomes more acidic, a difference that is already statistically significantly detectable in premenopausal, older women before FSH rises. This is not seen for LH glycoforms. CONCLUSION(S): The occurrence of postmenopausal-like acidic FSH isoforms precedes the rise of FSH before menopause.


Asunto(s)
Hormona Folículo Estimulante/análogos & derivados , Hormona Folículo Estimulante/sangre , Menopausia/sangre , Insuficiencia Ovárica Primaria/sangre , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
5.
Naunyn Schmiedebergs Arch Pharmacol ; 378(5): 503-14, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18551279

RESUMEN

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) activate the LH receptor/cyclic AMP (cAMP) signaling pathway to induce ovulation. As an alternative to parenterally administered hCG to treat anovulatory infertility, orally active low molecular weight (LMW) LHR agonists have been developed at Organon. In this paper, we present the mechanism of action of a prototypic, nanomolar potent and almost full LHR agonist, Org 43553. Org 43553 interacts with the endodomain of the LHR, whereas LH acts via the N-terminal exodomain. LH stimulates the cAMP pathway with an EC50 of 35 pM, but this stimulation is not antagonized by simultaneous incubation with Org 43553. At nanomolar concentrations, LH also stimulates phospholipase C (PLC), but Org 43553 is hardly able to do so. In contrast, Org 43553 inhibits LH-induced PLC (IC50 approximately 10 nM). While Org 43553 stimulates dissociation of [125I]hCG from the LHR and reduces [125I]hCG binding, LH reduces specific [3H]Org 43553 binding. We conclude that Org 43553 is a signaling-selective, allosteric LHR agonist. We hypothesize that Org 43553 and LH induce a similar LHR conformation necessary for activating adenylyl cyclase, which initiates most, if not all, physiological responses of LH.


Asunto(s)
Adenilil Ciclasas/metabolismo , AMP Cíclico/metabolismo , Pirimidinas/farmacología , Receptores de HL/agonistas , Tiofenos/farmacología , Regulación Alostérica , Animales , Células CHO , Línea Celular , Gonadotropina Coriónica/metabolismo , Cricetinae , Cricetulus , Humanos , Concentración 50 Inhibidora , Hormona Luteinizante/administración & dosificación , Hormona Luteinizante/farmacología , Pirimidinas/administración & dosificación , Transducción de Señal/efectos de los fármacos , Tiofenos/administración & dosificación , Fosfolipasas de Tipo C/efectos de los fármacos , Fosfolipasas de Tipo C/metabolismo
6.
Reprod Biomed Online ; 13(5): 687-95, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17169182

RESUMEN

Two very common single nucleotide polymorphisms at positions 307 and 680 in exon 10 of the FSH receptor gene have been associated with ovarian response in IVF. This observational study evaluated the role of the FSH receptor genotype in the prediction of poor response and clinical pregnancy in IVF in comparison with other markers, such as age, basal FSH, anti-Müllerian hormone and antral follicle count. In addition, the in-vitro cAMP response towards recombinant FSH in cultured granulosa cells of patients with different FSH receptor genotypes was determined. A total of 105 IVF patients undergoing ovarian stimulation in a long suppression protocol were included in the study. The ovarian response was comparable between patients with different FSH receptor genotypes. Patients with polymorphism Ser/Ser had implantation and pregnancy rates that were three times higher compared with patients with polymorphism Asn/Asn. FSH receptor genotype was not associated with a poor response in IVF, but showed a positive association with pregnancy, independent of age. There was no difference in cAMP production in cultured granulosa cells of patients with different FSH receptor genotypes (n=62). It is concluded that FSH receptor genotype is associated with pregnancy in IVF, but not with ovarian response.


Asunto(s)
Implantación del Embrión , Inducción de la Ovulación , Polimorfismo de Nucleótido Simple , Resultado del Embarazo , Receptores de HFE/genética , Adulto , AMP Cíclico/metabolismo , Femenino , Fertilización In Vitro , Genotipo , Humanos , Infertilidad , Oportunidad Relativa , Ovario/efectos de los fármacos , Ovario/fisiología , Embarazo , Estudios Prospectivos , Resultado del Tratamiento
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