Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 37
Filtrar
1.
Phytother Res ; 37(9): 3964-3981, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37186468

RESUMO

Doxorubicin (DOX), an effective chemotherapeutic drug, has been used to treat various cancers; however, its cardiotoxic side effects restrict its therapeutic efficacy. Fisetin, a flavonoid phytoestrogen derived from a range of fruits and vegetables, has been reported to exert cardioprotective effects against DOX-induced cardiotoxicity; however, the underlying mechanisms remain unclear. This study investigated fisetin's cardioprotective role and mechanism against DOX-induced cardiotoxicity in H9c2 cardiomyoblasts and ovariectomized (OVX) rat models. MTT assay revealed that fisetin treatment noticeably rescued DOX-induced cell death in a dose-dependent manner. Moreover, western blotting and TUNEL-DAPI staining showed that fisetin significantly attenuated DOX-induced cardiotoxicity in vitro and in vivo by inhibiting the insulin-like growth factor II receptor (IGF-IIR) apoptotic pathway through estrogen receptor (ER)-α/-ß activation. The echocardiography, biochemical assay, and H&E staining results demonstrated that fisetin reduced DOX-induced cardiotoxicity by alleviating cardiac dysfunction, myocardial injury, oxidative stress, and histopathological damage. These findings imply that fisetin has a significant therapeutic potential against DOX-induced cardiotoxicity.


Assuntos
Cardiotoxicidade , Fator de Crescimento Insulin-Like II , Ratos , Animais , Cardiotoxicidade/tratamento farmacológico , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like II/farmacologia , Fator de Crescimento Insulin-Like II/uso terapêutico , Receptores de Estrogênio/metabolismo , Doxorrubicina/efeitos adversos , Estresse Oxidativo , Miócitos Cardíacos , Apoptose
2.
Horm Res Paediatr ; 95(6): 619-630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36446332

RESUMO

The growth hormone (GH)-insulin-like growth factor (IGF) cascade is central to the regulation of growth and metabolism. This article focuses on the history of the components of the IGF system, with an emphasis on the peptide hormones, IGF-I and -II, their cell surface receptors, and the IGF binding proteins (IGFBPs) and IGFBP proteases that regulate the availability of the peptide hormones for interaction with their receptors in relevant target tissues. We describe landmark events in the evolution of the somatomedin hypothesis, including evidence that has become available from experiments at the molecular and cellular levels, whole animal and tissue-specific gene knockouts, studies of cancer epidemiology, identification of prismatic human cases, and short- and long-term clinical trials of IGF-I therapy in humans. In addition, this new evidence has expanded our clinical definition of GH insensitivity (GHI) beyond growth hormone receptor mutations (classic Laron syndrome) to include conditions that cause primary IGF deficiency by impacting post-receptor signal transduction, IGF production, IGF availability to interact with the IGF-I receptor (IGF-1R), and defects in the IGF-1R, itself. We also discuss the clinical aspects of IGFs, from their description as insulin-like activity, to the use of IGF-I in the diagnosis and treatment of GH deficiency, and to the use of recombinant human IGF-I for therapy of children with GHI.


Assuntos
Fator de Crescimento Insulin-Like II , Fator de Crescimento Insulin-Like I , Síndrome de Laron , Animais , Humanos , Fator de Crescimento Insulin-Like I/deficiência , Fator de Crescimento Insulin-Like I/história , Fator de Crescimento Insulin-Like I/fisiologia , Fator de Crescimento Insulin-Like I/uso terapêutico , Síndrome de Laron/tratamento farmacológico , Síndrome de Laron/genética , Síndrome de Laron/história , Síndrome de Laron/fisiopatologia , Hormônios Peptídicos , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Somatomedinas/deficiência , Somatomedinas/história , Somatomedinas/fisiologia , Fator de Crescimento Insulin-Like II/deficiência , Fator de Crescimento Insulin-Like II/história , Fator de Crescimento Insulin-Like II/fisiologia , Fator de Crescimento Insulin-Like II/uso terapêutico
3.
Contrast Media Mol Imaging ; 2022: 9198626, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845730

RESUMO

The study investigates the diagnostic efficacy of ultrasound combined with the molybdenum target mode in breast cancer staging and the relationship between blood flow parameters and the expression of insulin-like growth factor 1 (IGF-1) and factor 2 (IGF-2) and prognosis. A total of 96 patients admitted to hospital from January 2020 to January 2021 are included in the breast cancer group, and 58 patients admitted to our hospital during the same period are included in the control group, who are diagnosed with benign breast lesions. All patients receive clinicopathological diagnosis, ultrasound detection, and X-ray molybdenum detection. Ultrasound detection, molybdenum target detection, ultrasound combined with the molybdenum target detection mode, and clinicopathological diagnosis results are compared. B-ultrasound combined with the molybdenum target detection mode has high efficiency in diagnosing breast cancer and differentiating pathological stages. Besides, blood flow parameters of patients are closely related to IGF-1 and IGF-2, and IGF-1 and IGF-2 expressions are closely related to the prognosis of patients. Subsequent diagnosis of the disease degree of breast cancer patients can be carried out by ultrasound combined with the molybdenum target detection mode. In addition, the expression of IGF-1 and IGF-2 in patients can be monitored to improve the clinical diagnosis and treatment plan to improve the prognosis of patients, which has a high clinical application value and is worth promoting.


Assuntos
Neoplasias da Mama , Fator de Crescimento Insulin-Like I , Neoplasias da Mama/patologia , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/uso terapêutico , Fator de Crescimento Insulin-Like II/uso terapêutico , Molibdênio/uso terapêutico , Estadiamento de Neoplasias , Prognóstico
4.
Mol Autism ; 12(1): 59, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526125

RESUMO

BACKGROUND: Angelman Syndrome (AS) is a rare neurodevelopmental disorder for which there is currently no cure or effective therapeutic. Since the genetic cause of AS is known to be dysfunctional expression of the maternal allele of ubiquitin protein ligase E3A (UBE3A), several genetic animal models of AS have been developed. Both the Ube3a maternal deletion mouse and rat models of AS reliably demonstrate behavioral phenotypes of relevance to AS and therefore offer suitable in vivo systems in which to test potential therapeutics. One promising candidate treatment is insulin-like growth factor-2 (IGF-2), which has recently been shown to ameliorate behavioral deficits in the mouse model of AS and improve cognitive abilities across model systems. METHODS: We used both the Ube3a maternal deletion mouse and rat models of AS to evaluate the ability of IGF-2 to improve electrophysiological and behavioral outcomes. RESULTS: Acute systemic administration of IGF-2 had an effect on electrophysiological activity in the brain and on a metric of motor ability; however the effects were not enduring or extensive. Additional metrics of motor behavior, learning, ambulation, and coordination were unaffected and IGF-2 did not improve social communication, seizure threshold, or cognition. LIMITATIONS: The generalizability of these results to humans is difficult to predict and it remains possible that dosing schemes (i.e., chronic or subchronic dosing), routes, and/or post-treatment intervals other than that used herein may show more efficacy. CONCLUSIONS: Despite a few observed effects of IGF-2, our results taken together indicate that IGF-2 treatment does not profoundly improve behavioral deficits in mouse or rat models of AS. These findings shed cautionary light on the potential utility of acute systemic IGF-2 administration in the treatment of AS.


Assuntos
Síndrome de Angelman , Alelos , Síndrome de Angelman/tratamento farmacológico , Síndrome de Angelman/genética , Síndrome de Angelman/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like II/uso terapêutico , Camundongos , Ratos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
5.
Clin Exp Ophthalmol ; 48(9): 1261-1275, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33026147

RESUMO

BACKGROUND: Retinopathy of prematurity (ROP), a major cause of significant visual morbidity and blindness in preterm infants, is closely related to pathological angiogenesis. The aim of the study is to evaluate the effect of a new 12-aa peptide (named peptide CW-703) from human insulin-like growth factor-2, against angiogenesis in ROP. METHODS: In order to evaluate the inhibitory effect of CW-703 on the proliferation, migration, tube formation and apoptosis of human umbilical vein endothelial cells (ScienCell) in vitro, we used MTS assays, a modified Boyden chamber, Matrigel system and TUNEL assays. Effects in vivo were assayed using chorioallantoic membrane assays and oxygen-induced retinopathy (OIR) models in mice. We also performed eletrophysiological and histologic examinations to evaluate the possible toxicity of the peptide. Real-time PCR, ELISA and western blotting were used to elucidate the mechanism of CW-703. RESULTS: CW-703 inhibited angiogenesis in vitro by suppressing endothelial cell proliferation, migration and tube formation. CW-703 also prevented angiogenesis in chicken chorioallantoic membrane assays and OIR assays in mice. No evident functional or morphologic abnormalities in neuroretina after CW-703 injection were revealed in electrophysiological tests and histological examinations. Moreover, we elucidated that CW-703 competed for binding to IGF-1R and inhibited angiogenesis by inhibiting IGF-1R/PI3K/AKT activation and downregulating vascular endothelial growth factor expression. CONCLUSION: The novel peptide CW-703 may act as an effective inhibitor of ocular pathologic angiogenesis, especially in treating ROP.


Assuntos
Neovascularização Retiniana , Inibidores da Angiogênese/uso terapêutico , Animais , Proliferação de Células , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Fator de Crescimento Insulin-Like II/farmacologia , Fator de Crescimento Insulin-Like II/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica , Oxigênio/uso terapêutico , Oxigênio/toxicidade , Fosfatidilinositol 3-Quinases/farmacologia , Fosfatidilinositol 3-Quinases/uso terapêutico , Neovascularização Retiniana/induzido quimicamente , Neovascularização Retiniana/tratamento farmacológico , Neovascularização Retiniana/prevenção & controle , Fator A de Crescimento do Endotélio Vascular
6.
Drug Deliv Transl Res ; 10(2): 425-439, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31942701

RESUMO

BMN 250 is being developed as enzyme replacement therapy for Sanfilippo type B, a primarily neurological rare disease, in which patients have deficient lysosomal alpha-N-acetylglucosaminidase (NAGLU) enzyme activity. BMN 250 is taken up in target cells by the cation-independent mannose 6-phosphate receptor (CI-MPR, insulin-like growth factor 2 receptor), which then facilitates transit to the lysosome. BMN 250 is dosed directly into the central nervous system via the intracerebroventricular (ICV) route, and the objective of this work was to compare systemic intravenous (IV) and ICV delivery of BMN 250 to confirm the value of ICV dosing. We first assess the ability of enzyme to cross a potentially compromised blood-brain barrier in the Naglu-/- mouse model and then assess the potential for CI-MPR to be employed for receptor-mediated transport across the blood-brain barrier. In wild-type and Naglu-/- mice, CI-MPR expression in brain vasculature is high during the neonatal period but virtually absent by adolescence. In contrast, CI-MPR remains expressed through adolescence in non-affected non-human primate and human brain vasculature. Combined results from IV administration of BMN 250 in Naglu-/- mice and IV and ICV administration in healthy juvenile non-human primates suggest a limitation to therapeutic benefit from IV administration because enzyme distribution is restricted to brain vascular endothelial cells: enzyme does not reach target neuronal cells following IV administration, and pharmacological response following IV administration is likely restricted to clearance of substrate in endothelial cells. In contrast, ICV administration enables central nervous system enzyme replacement with biodistribution to target cells.


Assuntos
Acetilglucosaminidase/administração & dosagem , Acetilglucosaminidase/genética , Barreira Hematoencefálica/química , Fator de Crescimento Insulin-Like II/administração & dosagem , Mucopolissacaridose III/tratamento farmacológico , Receptor IGF Tipo 2/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Acetilglucosaminidase/uso terapêutico , Administração Intravenosa , Animais , Modelos Animais de Doenças , Terapia de Reposição de Enzimas , Feminino , Infusões Intraventriculares , Fator de Crescimento Insulin-Like II/uso terapêutico , Masculino , Camundongos , Camundongos Transgênicos , Mucopolissacaridose III/genética , Primatas , Proteínas Recombinantes de Fusão/uso terapêutico , Pesquisa Translacional Biomédica
7.
PLoS One ; 14(1): e0207836, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30657762

RESUMO

Sanfilippo syndrome type B (Sanfilippo B; Mucopolysaccharidosis type IIIB) occurs due to genetic deficiency of lysosomal alpha-N-acetylglucosaminidase (NAGLU) and subsequent lysosomal accumulation of heparan sulfate (HS), which coincides with devastating neurodegenerative disease. Because NAGLU expressed in Chinese hamster ovary cells is not mannose-6-phosphorylated, we developed an insulin-like growth factor 2 (IGF2)-tagged NAGLU molecule (BMN 250; tralesinidase alfa) that binds avidly to the IGF2 / cation-independent mannose 6-phosphate receptor (CI-MPR) for glycosylation independent lysosomal targeting. BMN 250 is currently being developed as an investigational enzyme replacement therapy for Sanfilippo B. Here we distinguish two cellular uptake mechanisms by which BMN 250 is targeted to lysosomes. In normal rodent-derived neurons and astrocytes, the majority of BMN250 uptake over 24 hours reaches saturation, which can be competitively inhibited with IGF2, suggestive of CI-MPR-mediated uptake. Kuptake, defined as the concentration of enzyme at half-maximal uptake, is 5 nM and 3 nM in neurons and astrocytes, with a maximal uptake capacity (Vmax) corresponding to 764 nmol/hr/mg and 5380 nmol/hr/mg, respectively. Similar to neurons and astrocytes, BMN 250 uptake in Sanfilippo B patient fibroblasts is predominantly CI-MPR-mediated, resulting in augmentation of NAGLU activity with doses of enzyme that fall well below the Kuptake (5 nM), which are sufficient to prevent HS accumulation. In contrast, uptake of the untagged recombinant human NAGLU (rhNAGLU) enzyme in neurons, astrocytes and fibroblasts is negligible at the same doses tested. In microglia, receptor-independent uptake, defined as enzyme uptake resistant to competition with excess IGF2, results in appreciable lysosomal delivery of BMN 250 and rhNAGLU (Vmax = 12,336 nmol/hr/mg and 5469 nmol/hr/mg, respectively). These results suggest that while receptor-independent mechanisms exist for lysosomal targeting of rhNAGLU in microglia, BMN 250, by its IGF2 tag moiety, confers increased CI-MPR-mediated lysosomal targeting to neurons and astrocytes, two additional critical cell types of Sanfilippo B disease pathogenesis.


Assuntos
Acetilglucosaminidase/metabolismo , Endocitose , Fator de Crescimento Insulin-Like II/uso terapêutico , Mucopolissacaridose III/tratamento farmacológico , Mucopolissacaridose III/patologia , Proteínas Recombinantes de Fusão/uso terapêutico , Acetilglucosaminidase/farmacocinética , Acetilglucosaminidase/uso terapêutico , Animais , Astrócitos/metabolismo , Axônios/metabolismo , Cátions , Fibroblastos/metabolismo , Heparitina Sulfato/metabolismo , Hipocampo/patologia , Humanos , Fator de Crescimento Insulin-Like II/farmacocinética , Lisossomos/enzimologia , Microglia/metabolismo , Ratos , Receptor IGF Tipo 2/metabolismo , Proteínas Recombinantes de Fusão/farmacocinética
8.
Cell Death Dis ; 9(2): 26, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29348399

RESUMO

Hepatocyte transplantation holds great promise as an alternative to orthotopic organ transplantation in the treatment of liver diseases. However, obtaining clinically meaningful levels of liver repopulation has not been achieved because the mechanisms regulating hepatocyte proliferation in recipient livers have not yet been well characterized. In the mouse model of Hereditary Tyrosinemia Type I, the fumarylacetoacetate hydrolase-deficient (Fah-/-) mouse, we found gradually increasing expression level of insulin-like growth factor 2 (IGF2) in the hepatocytes of host livers. Similarly, high levels of IGF2 were found in the livers of patients with deficient FAH activity. Recombinant IGF2 directly promotes proliferation of primary hepatocytes in vitro. Inhibition on IGF2 expression through the interruption of PI3K/Akt and MAPK pathways significantly reduced the level of liver repopulation in Fah-/- mice. Interestingly, treatment with IGF2 before hepatocyte transplantation generally improved the amount of liver repopulation seen in various mice models of liver injury. Altogether, these findings underscore the underlying mechanisms of therapeutic liver repopulation in Fah-/- mice, and indicate that IGF2 is a potential hepatocyte mitogen for liver cell transplantation therapies.


Assuntos
Fator de Crescimento Insulin-Like II/uso terapêutico , Fígado/efeitos dos fármacos , Animais , Proliferação de Células , Humanos , Fator de Crescimento Insulin-Like II/farmacologia , Camundongos
9.
Org Biomol Chem ; 14(39): 9225-9238, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27488745

RESUMO

Preptin is a 34-residue pancreatic hormone shown to be anabolic to bone in vitro and in vivo. The bone activity of preptin resides within the (1-16) N-terminal fragment. Due to its peptidic nature, the truncated fragment of preptin is enzymatically unstable; however it provides an attractive framework for the creation of stable analogues using various peptidomimetic techniques. An alanine scan of preptin (1-16) was undertaken which showed that substitution of Ser at position 3 or Pro at position 14 did not inhibit the proliferative activity of preptin in primary rat osteoblasts (bone-forming cells). Importantly, Ser-3 to Ala substitution also showed a significant activity on osteoblast differentiation in vitro and increased the formation of mineralised bone matrix. Additional modifications with non-proteinogenic amino acids at position 3 improved the stability in liver microsomes, but diminished the osteoblast proliferative activity. In addition, to provide greater structural diversity, a series of macrocyclic preptin (1-16) analogues was synthesised using head-to-tail and head-to-side chain macrolactamisation as well as ring-closing metathesis. However, a detrimental effect on osteoblast activity was observed upon macrocyclisation.


Assuntos
Anabolizantes/química , Anabolizantes/farmacologia , Osso e Ossos/efeitos dos fármacos , Fator de Crescimento Insulin-Like II/química , Fator de Crescimento Insulin-Like II/farmacologia , Osteoporose/tratamento farmacológico , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Sequência de Aminoácidos , Anabolizantes/metabolismo , Anabolizantes/uso terapêutico , Animais , Osso e Ossos/patologia , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like II/uso terapêutico , Microssomos Hepáticos/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteoporose/patologia , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/uso terapêutico , Estabilidade Proteica , Ratos , Relação Estrutura-Atividade
10.
Int J Oncol ; 47(5): 1881-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26397886

RESUMO

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide. Loss of imprinting (LOI) of the insulin-like growth factor 2 (IGF2) gene is an epigenetic abnormality phenomenon in CRC. Recently observed association of CRC with cluster of differentiation 147 (CD147) could provide a novel approach for gene therapy. In the present study, we investigated the feasibility of using adenovirus­mediated siRNA targeting CD147 based on the IGF2 LOI system for targeted gene therapy of CRC. A novel adenovirus-mediated siRNA targeting CD147, rAd-H19-CD147mirsh, which was driven by the IGF2 imprinting system, was constructed. The results showed that the EGFP expression was detected only in the IGF2 LOI cell lines (HT-29 and HCT-8), but that no EGFP was produced in cell lines with maintenance of imprinting (MOI) (HCT116). Moreover, rAd-H19-CD147mirsh significantly inhibited the expression of CD147, decreased cell viability and invasive ability, and increased sensitivity to chemotherapeutic drugs only in the LOI cell lines in vitro. Furthermore, mice bearing HT-29 xenografted tumors, which received intratumoral administration of the rAd-H19-CD147mirsh, showed significantly reduced tumor growth and enhanced survival. We conclude that recombinant adenovirus-mediated siRNA targeting CD147 based on the IGF2 LOI system inhibited the growth of the LOI cells in vitro and in vivo, which would provide a novel approach for targeted CRC gene therapy.


Assuntos
Basigina/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Terapia Genética , Fator de Crescimento Insulin-Like II/genética , Adenoviridae/genética , Animais , Basigina/uso terapêutico , Diferenciação Celular/genética , Sobrevivência Celular/genética , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Impressão Genômica , Células HT29 , Humanos , Fator de Crescimento Insulin-Like II/uso terapêutico , Camundongos , RNA Interferente Pequeno/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Cell Signal ; 27(6): 1025-38, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25744541

RESUMO

The number of people suffering from Alzheimer's disease (AD) will increase as the world population ages, creating a huge socio-economic burden. The three pathophysiological hallmarks of AD are the cholinergic system dysfunction, the ß-amyloid peptide deposition and the Tau protein hyperphosphorylation. Current treatments have only transient effects and each tends to concentrate on a single pathophysiological aspect of AD. This review first provides an overall view of AD in terms of its pathophysiological symptoms and signaling dysfunction. We then examine the therapeutic potential of growth factors (GFs) by showing how they can overcome the dysfunctional cell signaling that occurs in AD. Finally, we discuss new alternatives to GFs that help overcome the problem of brain uptake, such as small peptides, with evidence from some of our unpublished data on human neuronal cell line.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Transdução de Sinais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Proteínas Morfogenéticas Ósseas/uso terapêutico , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/uso terapêutico , Fator de Crescimento Insulin-Like II/uso terapêutico , Fator de Crescimento Neural/uso terapêutico , Fator de Crescimento Transformador beta1/uso terapêutico
12.
Proc Natl Acad Sci U S A ; 111(41): 14870-5, 2014 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-25267636

RESUMO

Mucopolysaccharidosis type IIIB (MPS IIIB, Sanfilippo syndrome type B) is a lysosomal storage disease characterized by profound intellectual disability, dementia, and a lifespan of about two decades. The cause is mutation in the gene encoding α-N-acetylglucosaminidase (NAGLU), deficiency of NAGLU, and accumulation of heparan sulfate. Impediments to enzyme replacement therapy are the absence of mannose 6-phosphate on recombinant human NAGLU and the blood-brain barrier. To overcome the first impediment, a fusion protein of recombinant NAGLU and a fragment of insulin-like growth factor II (IGFII) was prepared for endocytosis by the mannose 6-phosphate/IGFII receptor. To bypass the blood-brain barrier, the fusion protein ("enzyme") in artificial cerebrospinal fluid ("vehicle") was administered intracerebroventricularly to the brain of adult MPS IIIB mice, four times over 2 wk. The brains were analyzed 1-28 d later and compared with brains of MPS IIIB mice that received vehicle alone or control (heterozygous) mice that received vehicle. There was marked uptake of the administered enzyme in many parts of the brain, where it persisted with a half-life of approximately 10 d. Heparan sulfate, and especially disease-specific heparan sulfate, was reduced to control level. A number of secondary accumulations in neurons [ß-hexosaminidase, LAMP1(lysosome-associated membrane protein 1), SCMAS (subunit c of mitochondrial ATP synthase), glypican 5, ß-amyloid, P-tau] were reduced almost to control level. CD68, a microglial protein, was reduced halfway. A large amount of enzyme also appeared in liver cells, where it reduced heparan sulfate and ß-hexosaminidase accumulation to control levels. These results suggest the feasibility of enzyme replacement therapy for MPS IIIB.


Assuntos
Acetilglucosaminidase/uso terapêutico , Encéfalo/metabolismo , Sistemas de Liberação de Medicamentos , Fator de Crescimento Insulin-Like II/uso terapêutico , Mucopolissacaridose III/tratamento farmacológico , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/uso terapêutico , Animais , Biomarcadores/metabolismo , Encéfalo/patologia , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Endocitose , Fibroblastos/metabolismo , Fibroblastos/patologia , Heparitina Sulfato/metabolismo , Humanos , Injeções Intraventriculares , Fígado/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , Camundongos , Mucopolissacaridose III/patologia , Neurônios/metabolismo , Neurônios/patologia , Ligação Proteica , beta-N-Acetil-Hexosaminidases/metabolismo
13.
J Endocrinol ; 221(2): R41-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24883437

RESUMO

In the week following pancreatic islet transplantation, up to 50% of transplanted islets are lost due to apoptotic cell death triggered by hypoxic and pro-inflammatory cytokine-mediated cell stress. Thus, therapeutic approaches designed to protect islet cells from apoptosis could significantly improve islet transplant success. IGF2 is an anti-apoptotic endocrine protein that inhibits apoptotic cell death through the mitochondrial (intrinsic pathway) or via antagonising activation of pro-inflammatory cytokine signalling (extrinsic pathway), in doing so IGF2 has emerged as a promising therapeutic molecule to improve islet survival in the immediate post-transplant period. The development of novel biomaterials coated with IGF2 is a promising strategy to achieve this. This review examines the mechanisms mediating islet cell apoptosis in the peri- and post-transplant period and aims to identify the utility of IGF2 to promote islet survival and enhance long-term insulin independence rates within the setting of clinical islet transplantation.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Sobrevivência de Enxerto/efeitos dos fármacos , Fator de Crescimento Insulin-Like II/fisiologia , Fator de Crescimento Insulin-Like II/uso terapêutico , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/fisiologia , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Transferência de Genes , Terapia Genética , Humanos , Mediadores da Inflamação/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos
14.
Rev Neurosci ; 25(4): 559-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24778346

RESUMO

In the current aging society, cognitive dysfunction is one of the most serious issues that should be urgently resolved. It also affects a wide range of age groups harboring neurological and psychiatric disorders, such as Alzheimer's disease and schizophrenia. Although the molecular mechanism of memory impairment still remains to be determined, neuronal loss and dysfunction has been revealed to mainly attribute to its pathology. The discovery of neural stem cells in the adult brain that are proliferating and able to generate functional neurons has given rise to the idea that neuronal loss could be rescued by manipulating endogenous neural progenitor and stem cells. To this end, we must characterize them in detail and their developmental programming must be better understood. A growing body of evidence has indicated that insulin-like peptides are involved in learning and memory and maintenance of neural progenitor and stem cells, and clinical trials of insulin as a memory enhancer have begun. In contrast to the expectation of insulin and IGF1, the roles of IGF2 in cognitive ability have been poorly understood. However, recent evidence demonstrated in rodents suggests that IGF2 may play a pivotal role in adult neurogenesis and cognitive function. Here, we would like to review the rapidly growing world of IGF2 in cognitive neuroscience and introduce the evidence that its deficit is indeed involved in the impairment of the hippocampal neurogenesis and cognitive dysfunction in the model mouse of 22q11.2 deletion syndrome, which deletes Dgcr8, a critical gene for microRNA processing.


Assuntos
Disfunção Cognitiva/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Memória , Neurogênese , Animais , Disfunção Cognitiva/tratamento farmacológico , Modelos Animais de Doenças , Hipocampo/metabolismo , Humanos , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/uso terapêutico , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
15.
Ann Thorac Surg ; 91(3): 784-91, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21352998

RESUMO

BACKGROUND: Lethal reperfusion injury has been associated with apoptotic cell death. Insulin and insulin-like growth factors (IGF-I/IGF-II) may modulate this cell death when administered at the onset of reperfusion after ischemia. We explored if antiapoptotic treatment with IGF-II could influence left ventricular function in an experimental model with cardiopulmonary bypass and repeated oxygenated blood cardioplegia. METHODS: Twenty pigs underwent cardiopulmonary bypass with aortic cross-clamping for 60 minutes. In controls, hearts were arrested with cold, oxygenated blood cardioplegia repeated after 20 and 40 minutes. In the intervention group IGF-II was added to the cardioplegic solution at 20 and 40 minutes. After declamping and weaning from cardiopulmonary bypass, left ventricular global and local function was evaluated with a conductance catheter and tissue velocity imaging. Three hours after declamping the anterior left ventricle wall was divided in three layers and studied for blood flow rate with microspheres, Akt phosphorylation, and caspase-3 cleavage. Troponin-T levels were measured at baseline and after 3 hours of reperfusion. RESULTS: A reduction of myocardial levels of cleaved caspase-3 (p < 0.001) was found in the subendocardial wall layer and serum troponin-T was reduced (p < 0.025) in the IGF-II group 3 hours after declamping. In the IGF-II treated animals, left ventricular preload recruitable stroke work was low 1 hour after declamping and increased to levels higher than in controls (p < 0.025) 3 hours after declamping. Other cardiac variables did not differ between groups. CONCLUSIONS: When added to repeated cold blood cardioplegia, IGF-II reduces apoptosis and ischemia-reperfusion injury with minor effects on cardiac function.


Assuntos
Apoptose/efeitos dos fármacos , Soluções Cardioplégicas/farmacologia , Parada Cardíaca Induzida , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Função Ventricular Esquerda/fisiologia , Animais , Western Blotting , Caspase 3/metabolismo , Modelos Animais de Doenças , Feminino , Fator de Crescimento Insulin-Like II/uso terapêutico , Masculino , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Suínos , Troponina T/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos
17.
Curr Opin Mol Ther ; 12(3): 361-71, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20521225

RESUMO

Dalotuzumab (MK-0646; h7C10), being developed by Merck & Co Inc under license from Pierre Fabre SA, is a recombinant humanized IgG1 mAb against the IGFR1 for the potential intravenous treatment of cancer. Preclinical studies have demonstrated that dalotuzumab acts by inhibiting IGF-1- and IGF-2-mediated tumor cell proliferation, IGFR1 autophosphorylation and Akt phosphorylation. In multiple cancer cell lines and in mouse xenograft models, dalotuzumab displayed significant antitumor activity, in particular against NSCLC and breast cancer. In addition, coadministration of dalotuzumab with other anticancer agents, such as taxanes, enhanced the in vitro and in vivo antitumor activity of dalotuzumab. Preliminary data from phase I clinical trials suggest that dalotuzumab is safe, well tolerated and significantly inhibits tumor proliferation. At the time of publication, several clinical trials evaluating dalotuzumab, alone and in combination with other anticancer agents, were ongoing in patients with various types of solid tumor and in patients with multiple myeloma. Although preliminary results appear promising, only future clinical and translational data will clarify the best clinical setting and treatment combinations for the optimal use of dalotuzumab in clinical practice.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Terapia Combinada , Feminino , Humanos , Fator de Crescimento Insulin-Like I/uso terapêutico , Fator de Crescimento Insulin-Like II/uso terapêutico , Camundongos , Camundongos Nus , Mieloma Múltiplo/tratamento farmacológico , Neoplasias do Sistema Nervoso/tratamento farmacológico
18.
Neuroreport ; 20(16): 1414-8, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19738502

RESUMO

The search for therapeutic targets to prevent neurons from dying is ongoing and involves the exploration of a long list of neurotrophic factors. Insulin-like growth factor 2 (IGF2) is a member of the insulin family with known neurotrophic properties. In this study, we used Igf2 knockout (Igf2) neonate mice to determine whether Igf2 deficiency is detrimental to motor neuron survival after axonal injury. Results show that Igf2 neonatal mice are more susceptible to motor neuron damage than Igf2 mice, as they have a significantly lower percentage of motor neuron survival after a sciatic nerve transection. Neuronal survival was significantly improved in Igf2 mice when IGF2 was administered. These results support the role of IGF2 in neonatal motor neuron survival.


Assuntos
Fator de Crescimento Insulin-Like II/deficiência , Neurônios Motores/fisiologia , Neuropatia Ciática/patologia , Neuropatia Ciática/fisiopatologia , Animais , Animais Recém-Nascidos , Contagem de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Fator de Crescimento Insulin-Like II/uso terapêutico , Camundongos , Camundongos Knockout , Neurônios Motores/efeitos dos fármacos , Neuropatia Ciática/tratamento farmacológico
20.
Unfallchirurg ; 110(9): 792-6, 2007 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-17823782

RESUMO

BACKGROUND: Besides basic, illness- and patient-oriented research, outcomes research is regarded as the fourth pillar of modern health care systems. Outcomes research investigates both the desirable and adverse effects of medical and surgical interventions under day-to-day conditions. METHOD: Because of rigorous entry criteria and selection of eligible subjects, the efficacy of a certain treatment derived from clinical experiments (i.e. classic randomized trials) may not necessarily be transferred to common patient populations or clinical settings. Apart from efficacy, a valuable (thus reimbursable) diagnostic or therapeutic procedure must prove its effectiveness in clinical practice as well. Demanding study designs are necessary to model effectiveness and to separate the observed intervention-related effects from bias and confounding. RESULTS: Registries and pragmatic randomized trials may represent the most appropriate modalities to establish outcomes research in trauma and orthopaedic surgery. Good examples for interventions still needing proof of effectiveness are kyphoplasty and vertebroplasty, navigated surgery, damage control, interlocking implants and bone growth factors. Revealing over- and undersupply, generating negative lists (i.e. interventions of questionable or almost nil effectiveness) and integrating patients as co-therapists requires networking between hospitals and private practitioners. CONCLUSION: Also, since outcomes research is a societal need, its development and funding must be ensured by all providers and payers of health care services.


Assuntos
Medicina Baseada em Evidências , Pesquisa sobre Serviços de Saúde/métodos , Programas Nacionais de Saúde , Avaliação de Resultados em Cuidados de Saúde/métodos , Ferimentos e Lesões/cirurgia , Comportamento Cooperativo , Análise Custo-Benefício , Medicina Baseada em Evidências/economia , Fixação Intramedular de Fraturas/economia , Fixação Intramedular de Fraturas/métodos , Alemanha , Humanos , Fator de Crescimento Insulin-Like II/economia , Fator de Crescimento Insulin-Like II/uso terapêutico , Programas Nacionais de Saúde/economia , Equipe de Assistência ao Paciente/economia , Garantia da Qualidade dos Cuidados de Saúde/economia , Garantia da Qualidade dos Cuidados de Saúde/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Cirurgia Assistida por Computador/economia , Cirurgia Assistida por Computador/métodos , Procedimentos Desnecessários/economia , Vertebroplastia/economia , Vertebroplastia/métodos , Ferimentos e Lesões/economia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA