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1.
Mol Cell ; 55(6): 807-817, 2014 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-25155611

RESUMEN

Maternal metabolism provides essential nutrients to enable embryonic development. However, both mother and embryo produce reactive metabolites that can damage DNA. Here we discover how the embryo is protected from these genotoxins. Pregnant mice lacking Aldh2, a key enzyme that detoxifies reactive aldehydes, cannot support the development of embryos lacking the Fanconi anemia DNA repair pathway gene Fanca. Remarkably, transferring Aldh2(-/-)Fanca(-/-) embryos into wild-type mothers suppresses developmental defects and rescues embryonic lethality. These rescued neonates have severely depleted hematopoietic stem and progenitor cells, indicating that despite intact maternal aldehyde catabolism, fetal Aldh2 is essential for hematopoiesis. Hence, maternal and fetal aldehyde detoxification protects the developing embryo from DNA damage. Failure of this genome preservation mechanism might explain why birth defects and bone marrow failure occur in Fanconi anemia, and may have implications for fetal well-being in the many women in Southeast Asia that are genetically deficient in ALDH2.


Asunto(s)
Acetaldehído/metabolismo , Aldehído Deshidrogenasa/genética , Aldehído Deshidrogenasa/metabolismo , Embrión de Mamíferos/metabolismo , Etanol/toxicidad , Proteína del Grupo de Complementación A de la Anemia de Fanconi/genética , Anemia de Fanconi/patología , Acetaldehído/toxicidad , Familia de Aldehído Deshidrogenasa 1 , Aldehído Deshidrogenasa Mitocondrial , Animales , Animales Recién Nacidos , Daño del ADN , Modelos Animales de Enfermedad , Embrión de Mamíferos/embriología , Femenino , Genoma , Células Madre Hematopoyéticas/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Ratones , Ratones Endogámicos C57BL , Embarazo , Retinal-Deshidrogenasa/genética , Retinal-Deshidrogenasa/metabolismo
2.
Mucosal Immunol ; 14(1): 26-37, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32457448

RESUMEN

Type-2 immunity is characterised by interleukin (IL)-4, IL-5 and IL-13, eosinophilia, mucus production, IgE, and alternatively activated macrophages (AAM). However, despite the lack of neutrophil chemoattractants such as CXCL1, neutrophils, a feature of type-1 immunity, are observed in type-2 responses. Consequently, alternative mechanisms must exist to ensure that neutrophils can contribute to type-2 immune reactions without escalation of deleterious inflammation. We now demonstrate that type-2 immune-associated neutrophil infiltration is regulated by the mouse RNase A homologue, eosinophil-associated ribonuclease 11 (Ear11), which is secreted by AAM downstream of IL-25-stimulated ILC2. Transgenic overexpression of Ear11 resulted in tissue neutrophilia, whereas Ear11-deficient mice have fewer resting tissue neutrophils, whilst other type-2 immune responses are not impaired. Notably, administration of recombinant mouse Ear11 increases neutrophil motility and recruitment. Thus, Ear11 helps maintain tissue neutrophils at homoeostasis and during type-2 reactions when chemokine-producing classically activated macrophages are infrequently elicited.


Asunto(s)
Inmunidad Innata , Linfocitos/fisiología , Activación de Macrófagos/inmunología , Macrófagos/fisiología , Infiltración Neutrófila/inmunología , Neutrófilos/fisiología , Ribonucleasas/biosíntesis , Animales , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Eosinófilos/inmunología , Eosinófilos/metabolismo , Inmunomodulación , Inmunofenotipificación , Interleucina-13/biosíntesis , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones Transgénicos , Ribonucleasas/genética
3.
Pharmaceutics ; 11(6)2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-31181662

RESUMEN

Nasal delivery of large peptides such as parathyroid 1-34 (PTH 1-34) can benefit from a permeation enhancer to promote absorption across the nasal mucosa into the bloodstream. Previously, we have published an encouraging bioavailability (78%), relative to subcutaneous injection in a small animal preclinical model, for a liquid nasal spray formulation containing the permeation enhancer polyethylene glycol (15)-hydroxystearate (Solutol® HS15). We report here the plasma pharmacokinetics of PTH 1-34 in healthy human volunteers receiving the liquid nasal spray formulation containing Solutol® HS15. For comparison, data for a commercially manufactured teriparatide formulation delivered via subcutaneous injection pen are also presented. Tc-99m-DTPA gamma scintigraphy monitored the deposition of the nasal spray in the nasal cavity and clearance via the inferior meatus and nasopharynx. The 50% clearance time was 17.8 min (minimum 10.9, maximum 74.3 min). For PTH 1-34, mean plasma Cmax of 5 pg/mL and 253 pg/mL were obtained for the nasal spray and subcutaneous injection respectively; relative bioavailability of the nasal spray was ≤1%. Subsequently, we investigated the pharmacokinetics of the liquid nasal spray formulation as well as a dry powder nasal formulation also containing Solutol® HS15 in a crossover study in an established ovine model. In this preclinical model, the relative bioavailability of liquid and powder nasal formulations was 1.4% and 1.0% respectively. The absolute bioavailability of subcutaneously administered PTH 1-34 (mean 77%, range 55-108%) in sheep was in agreement with published human data for teriparatide (up to 95%). These findings have important implications in the search for alternative routes of administration of peptides for the treatment of osteoporosis, and in terms of improving translation from animal models to humans.

4.
Int J Pharm ; 535(1-2): 113-119, 2018 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-29038066

RESUMEN

Osteoporosis treatment with PTH 1-34 injections significantly reduces the incidence of bone fracture. Potential further reductions in fracture rate should be observed through nasal spray delivery to address the poor compliance associated with patient dislike of repeated PTH 1-34 subcutaneous injections. In vitro human osteoblast-like Saos-2 cell intracellular cAMP levels were used to define PTH 1-34 nasal spray formulation bioactivity. The chemically synthesised PTH 1-34 had an EC50 of 0.76nM. Absorption enhancers polyethylene glycol (15)-hydroxystearate (Solutol® HS15), poloxamer 407, chitosan or sodium hyaluronate did not diminish the bioactivity of PTH 1-34 within an in vitro cell culture model (p >0.05). We also demonstrated the effectiveness of the transmucosal absorption enhancer Solutol® HS15 in a nasal spray formulation using a preclinical pharmacokinetic model. In Sprague-Dawley rats without the absorption enhancer the uptake of PTH 1-34 into the blood via intranasal delivery produced a Cmax of 2.1±0.5ng/ml compared to 13.7±1.6ng/ml with Solutol® HS15 enhancer (p=0.016) and a Cmax14.8±8ng/ml in subcutaneous injections. Together these data illustrate that the nasal spray formulation bioactivity in vitro is not affected by the nasal spray absorption enhancers investigated, and the Solutol® HS15 nasal spray formulation had an equivalent pharmacokinetic profile to subcutaneous injection in the rat model. The Solutol® HS15 formulation therefore demonstrated potential as a PTH 1-34 nasal spray formulation for the treatment of osteoporosis.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Osteoblastos/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Teriparatido/administración & dosificación , Adyuvantes Farmacéuticos/química , Administración Intranasal , Animales , Disponibilidad Biológica , Conservadores de la Densidad Ósea/química , Conservadores de la Densidad Ósea/farmacocinética , Línea Celular , Evaluación Preclínica de Medicamentos , Humanos , Masculino , Absorción Nasal , Osteoblastos/metabolismo , Polietilenglicoles/química , Ratas Sprague-Dawley , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Ácidos Esteáricos/química , Teriparatido/química , Teriparatido/farmacocinética
5.
J Clin Endocrinol Metab ; 100(11): 4364-71, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26425883

RESUMEN

CONTEXT: The development of an improved, efficacious human GH (hGH) product administered by a noninjectable route of delivery such as the nasal route is highly desirable. We have developed a novel nasal hGH product (CP024) that showed excellent nasal absorption in animal models; however, the translation of these results into the clinical setting is essential because past attempts to develop such formulations by other groups have been unable to induce IGF-1 in man. OBJECTIVE: The objective of the study was to assess the pharmacokinetics, pharmacodynamics, and tolerability of CP024 compared with a sc hGH injection. DESIGN: This was a single-center, nonrandomized placebo-controlled, open-label, five-way crossover study in eight healthy volunteers. SETTING: The study was carried out at a contract research organization, Quotient Bioresearch. VOLUNTEERS: Eight healthy male volunteers, given an iv infusion of octreotide to suppress the endogenous GH secretion during the study period, participated in the study. No volunteers were withdrawn due to side effects. MAIN OUTCOME MEASURES: Measurement of hGH and IGF-1 levels and tolerability of the drug product was performed. RESULTS: No serious adverse events were reported and no subjects withdrawn from study due to the treatment. After the nasal administration of CP024, 3-fold higher hGH blood levels were obtained as compared with hGH nasal control. The relative bioavailability was about 3%. CP024 (given twice daily) induced a significant increase in IGF-1 levels up to 19 hours after administration, with no significant difference to those obtained after the sc injection of hGH. CONCLUSIONS: The study indicates that CP024 is a promising candidate for an efficacious nasal product for the treatment of GH deficiency due to induction of IGF-1 similar to that after a sc injection, despite the lower plasma hGH concentration obtained. A dose-response study is needed to evaluate the optimal nasal dose.


Asunto(s)
Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/farmacología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Administración Intranasal , Adulto , Química Farmacéutica , Estudios Cruzados , Voluntarios Sanos , Hormona de Crecimiento Humana/farmacocinética , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Octreótido/farmacología , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Adulto Joven
7.
Rev. bras. entomol ; 58(2): 103-106, Apr.-June 2014. ilus
Artículo en Inglés | LILACS | ID: lil-714736

RESUMEN

Rhodometra sacraria (Linnaeus), a cosmopolitan sterrhine confirmed from Chile (Lepidoptera, Geometridae). Rhodometra sacraria (Linnaeus, 1767), corologically a cosmopolitan species, is documented from Chile thanks to the analysis of specimens from four different localities in that country, at the same time, increasing the number of species known from the subfamily Sterrhinae in Chile, as well as being only the second (confirmed) documentation of this species from the Neotropics.

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