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1.
Eur J Neurosci ; 59(8): 1993-2015, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382910

RESUMO

A common pathological hallmark of neurodegenerative disorders is neuronal cell death, accompanied by neuroinflammation and oxidative stress. The vasoactive intestinal peptide (VIP) is a pleiotropic peptide that combines neuroprotective and immunomodulatory actions. The gene therapy field shows long-term promise for treating a wide range of neurodegenerative diseases (ND). In this study, we aimed to investigate the in vitro efficacy of transduction of microglia using lentiviral gene therapy vectors encoding VIP (LentiVIP). Additionally, we tested the protective effects of the secretome derived from LentiVIP-infected "immortalized human" microglia HMC3 cells, and cells treated with Synthetic VIP (SynVIP), against toxin-induced neurodegeneration. First, LentiVIP, which stably expresses VIP, was generated and purified. VIP secretion in microglial conditioned media (MG CM) for LentiVIP-infected HMC3 microglia cells was confirmed. Microglia cells were activated with lipopolysaccharide, and groups were formed as follows: 1) Control, 2) SynVIP-treated, or 3) LentiVIP-transduced. These MG CM were applied on an in vitro neurodegenerative model formed by differentiated (d)-SH-SY5Y cells. Then, cell survival analysis and apoptotic nuclear staining, besides measurement of oxidative/inflammatory parameters in CM of cells were performed. Activated MG CM reduced survival rates of both control and toxin-applied (d)-SH-SY5Y cells, whereas LentiVIP-infected MG CM and SynVIP-treated ones exhibited better survival rates. These findings were supported by apoptotic nuclear evaluations of (d)-SH-SY5Y cells, alongside oxidative/inflammatory parameters in their CM. LentiVIP seems worthy of further studies for the treatment of ND because of the potential of gene therapy to treat diseases effectively with a single injection.


Assuntos
Neuroblastoma , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Humanos , Peptídeo Intestinal Vasoativo/farmacologia , Peptídeo Intestinal Vasoativo/metabolismo , Microglia/metabolismo , Neuroblastoma/metabolismo , Doenças Neurodegenerativas/metabolismo , Terapia Genética , Fármacos Neuroprotetores/farmacologia
2.
Adv Exp Med Biol ; 1409: 145-159, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36289162

RESUMO

Since insulin deficiency results from pancreatic beta-cell destruction, all type 1 and most type 2 diabetes patients eventually require life-long insulin injections. Insulin gene synthesis could also be impaired due to insulin gene mutations as observed in diabetic patients with MODY 10. At this point, insulin gene therapy could be very effective to recompense insulin deficiency under these circumstances. For this reason, an HIV-based lentiviral vector carrying the insulin gene under the control of insulin promoter (LentiINS) was generated, and its therapeutic efficacy was tested in a beta-cell transplant model lacking insulin produced by CRISPR/Cas9-mediated genetically engineered pancreatic beta cells. To generate an insulin knockout beta-cell transplant animal model of diabetes, a dual gene knockout plasmid system involving CRISPR/Cas9 was transfected into a mouse pancreatic beta cell line (Min6). Fluorescence microscopy and antibiotic selection were utilized to select the insulin gene knockout clones. Transplantation of the genetically engineered pancreatic beta cells under the kidney capsule of STZ-induced diabetic rats revealed LentiINS- but not LentiLacZ-infected Ins2KO cells transiently reduced hyperglycemia similar to that of MIN6 in diabetic animals. These results suggest LentiINS has the potential to functionally restore insulin production in an insulin knockout beta-cell transplant animal model of diabetes.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Camundongos , Animais , Ratos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Experimental/metabolismo , Insulina/genética , Insulina/metabolismo , Animais Geneticamente Modificados , Células Secretoras de Insulina/metabolismo , Modelos Animais , Transplante de Células/métodos
3.
World J Stem Cells ; 13(6): 485-502, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34249224

RESUMO

Targeted genome editing is a continually evolving technology employing programmable nucleases to specifically change, insert, or remove a genomic sequence of interest. These advanced molecular tools include meganucleases, zinc finger nucleases, transcription activator-like effector nucleases and RNA-guided engineered nucleases (RGENs), which create double-strand breaks at specific target sites in the genome, and repair DNA either by homologous recombination in the presence of donor DNA or via the error-prone non-homologous end-joining mechanism. A recently discovered group of RGENs known as CRISPR/Cas9 gene-editing systems allowed precise genome manipulation revealing a causal association between disease genotype and phenotype, without the need for the reengineering of the specific enzyme when targeting different sequences. CRISPR/Cas9 has been successfully employed as an ex vivo gene-editing tool in embryonic stem cells and patient-derived stem cells to understand pancreatic beta-cell development and function. RNA-guided nucleases also open the way for the generation of novel animal models for diabetes and allow testing the efficiency of various therapeutic approaches in diabetes, as summarized and exemplified in this manuscript.

4.
Hum Gene Ther ; 32(11-12): 541-562, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33858231

RESUMO

Severe acute respiratory syndrome (SARS) is a newly emerging infectious disease (COVID-19) caused by the novel coronavirus SARS-coronavirus 2 (CoV-2). To combat the devastating spread of SARS-CoV-2, extraordinary efforts from numerous laboratories have focused on the development of effective and safe vaccines. Traditional live-attenuated or inactivated viral vaccines are not recommended for immunocompromised patients as the attenuated virus can still cause disease via phenotypic or genotypic reversion. Subunit vaccines require repeated dosing and adjuvant use to be effective, and DNA vaccines exhibit lower immune responses. mRNA vaccines can be highly unstable under physiological conditions. On the contrary, naturally antigenic viral vectors with well-characterized structure and safety profile serve as among the most effective gene carriers to provoke immune response via heterologous gene transfer. Viral vector-based vaccines induce both an effective cellular immune response and a humoral immune response owing to their natural adjuvant properties via transduction of immune cells. Consequently, viral vectored vaccines carrying the SARS-CoV-2 spike protein have recently been generated and successfully used to activate cytotoxic T cells and develop a neutralizing antibody response. Recent progress in SARS-CoV-2 vaccines, with an emphasis on gene therapy viral vector-based vaccine development, is discussed in this review.


Assuntos
Vacinas contra COVID-19/farmacologia , Vetores Genéticos , Vacinas Atenuadas/farmacologia , Vacinas Sintéticas/farmacologia , Proteínas Estruturais Virais/química , Adenoviridae/genética , Terapia Genética/métodos , Vetores Genéticos/química , Vetores Genéticos/genética , Humanos , Lentivirus/genética , SARS-CoV-2/genética , Vacinas de DNA/farmacologia , Proteínas Estruturais Virais/genética , Proteínas Estruturais Virais/metabolismo , Vacinas de mRNA
5.
Gene Ther ; 28(3-4): 130-141, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32733091

RESUMO

Type 1 diabetes (T1DM) is an autoimmune condition in which the immune system attacks and destroys insulin-producing beta cells in the pancreas leading to hyperglycemia. Vasoactive intestinal peptide (VIP) manifests insulinotropic and anti-inflammatory properties, which are useful for the treatment of diabetes. Because of its limited half-life due to DPP-4-mediated degradation, constant infusions or multiple injections are needed to observe any therapeutic benefit. Since gene therapy has the potential to treat genetic diseases, an HIV-based lentiviral vector carrying VIP gene (LentiVIP) was generated to provide a stable VIP gene expression in vivo. The therapeutic efficacy of LentiVIP was tested in a multiple low-dose STZ-induced animal model of T1DM. LentiVIP delivery into diabetic animals reduced hyperglycemia, improved glucose tolerance, and prevented weight loss. Also, a decrease in serum CRP levels, and serum oxidant capacity, but an increase in antioxidant capacity were observed in LentiVIP-treated animals. Restoration of islet cell mass was correlated with an increase in pancreatic beta-cell proliferation. These beneficial results suggest the therapeutic effect of LentiVIP is due to the repression of diabetes-induced inflammation, its insulinotropic properties, and VIP-induced beta-cell proliferation.


Assuntos
Diabetes Mellitus Tipo 1 , Peptídeo Intestinal Vasoativo , Animais , Proliferação de Células , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/terapia , Terapia Genética , Inflamação/terapia , Insulina , Peptídeo Intestinal Vasoativo/genética
6.
Mol Ther ; 29(1): 149-161, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33130311

RESUMO

Autoimmune destruction of pancreatic beta cells is the characteristic feature of type 1 diabetes mellitus. Consequently, both short- and intermediate-acting insulin analogs are under development to compensate for the lack of endogenous insulin gene expression. Basal insulin is continuously released at low levels in response to hepatic glucose output, while post-prandial insulin is secreted in response to hyperglycemia following a meal. As an alternative to multiple daily injections of insulin, glucose-regulated insulin gene expression by gene therapy is under development to better endure postprandial glucose excursions. Controlled transcription and translation of proinsulin, presence of glucose-sensing machinery, prohormone convertase expression, and a regulated secretory pathway are the key features unique to pancreatic beta cells. To take advantage of these hallmarks, we generated a new lentiviral vector (LentiINS) with an insulin promoter driving expression of the proinsulin encoding cDNA to sustain pancreatic beta-cell-specific insulin gene expression. Intraperitoneal delivery of HIV-based LentiINS resulted in the lowering of fasting plasma glucose, improved glucose tolerance and prevented weight loss in streptozoticin (STZ)-induced diabetic Wistar rats. However, the combinatorial use of LentiINS and anti-inflammatory lentiviral vector (LentiVIP) gene therapy was required to increase serum insulin to a level sufficient to suppress non-fasting plasma glucose and diabetes-related inflammation.


Assuntos
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/terapia , Terapia Genética , Vetores Genéticos/genética , Células Secretoras de Insulina/metabolismo , Insulina/genética , Lentivirus/genética , Animais , Biomarcadores , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Vetores Genéticos/administração & dosagem , Glucose/metabolismo , Insulina/metabolismo , Ratos , Ratos Wistar , Resultado do Tratamento
7.
Methods Mol Biol ; 1879: 323-345, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29797007

RESUMO

Lentiviral vectors are becoming preferred vectors of choice for clinical gene therapy trials due to their safety, efficacy, and the long-term gene expression they provide. Although the efficacy of lentiviral vectors is mainly predetermined by the therapeutic genes they carry, they must be produced at high titers to exert therapeutic benefit for in vivo applications. Thus, there is need for practical, robust, and scalable viral vector production methods applicable to any laboratory setting. Here, we describe a practical lentiviral production technique in roller bottles yielding high-titer third-generation lentiviral vectors useful for in vivo gene transfer applications. CaPO4-mediated transient transfection protocol involving the use of a transfer vector and three different packaging plasmids is employed to generate lentivectors in roller bottles. Following clearance of cellular debris via low-speed centrifugation and filtration, virus is concentrated by high-speed ultracentrifugation over sucrose cushion.


Assuntos
Vetores Genéticos/genética , HIV/genética , Lentivirus/genética , Linhagem Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Técnicas de Transferência de Genes , Terapia Genética/métodos , Células HEK293 , Humanos , Plasmídeos/genética , Transdução Genética/métodos , Transfecção/métodos , Ultracentrifugação/métodos
8.
Methods Mol Biol ; 1879: 347-365, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30006865

RESUMO

Lentiviral vectors (LVs) have been increasingly used in clinical gene therapy applications particularly due to their efficient gene transfer ability, lack of interference from preexisting viral immunity, and long-term gene expression they provide. Purity of LVs is essential in in vivo applications, for a high therapeutic benefit with minimum toxicity. Accordingly, laboratory scale production of LVs frequently involves transient cotransfection of 293T cells with packaging and transfer plasmids in the presence of CaPO4. After clearance of the cellular debris by low-speed centrifugation and filtration, lentivectors are usually concentrated by high-speed ultracentrifugation in sucrose cushion. Concentrated viral samples are then purified by anion exchange chromatography (AEX) after benzonase treatment to remove the residual cellular DNA. Here, we describe an improved practical method for LV purification using AEX, useful for experimental studies concerning gene and stem cell therapy.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Cromatografia por Troca Iônica/métodos , Terapia Genética , Vetores Genéticos/isolamento & purificação , HIV/genética , Lentivirus/genética , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Transdução Genética
9.
Gene Ther ; 25(4): 269-283, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29523882

RESUMO

Type 2 diabetes mellitus (T2DM) is characterised by insulin resistance, glucose intolerance and beta cell loss leading to hyperglycemia. Vasoactive intestinal peptide (VIP) has been regarded as a novel therapeutic agent for the treatment of T2DM because of its insulinotropic and anti-inflammatory properties. Despite these beneficial properties, VIP is extremely sensitive to peptidases (DPP-4) requiring constant infusion or multiple injections to observe any therapeutic benefit. Thus, we constructed an HIV-based lentiviral vector encoding human VIP (LentiVIP) to test the therapeutic efficacy of VIP peptide in a diet-induced obesity (DIO) animal model of T2DM. VIP gene expression was shown by immunocytochemistry (ICC) and VIP peptide secretion was confirmed by ELISA both in HepG2 liver and MIN6 pancreatic beta cell lines. Functional properties of VIP were demonstrated by cAMP production assay and glucose-stimulated insulin secretion test (GSIS). Intraperitoneal (IP) delivery of LentiVIP vectors into mice significantly increased serum VIP concentrations compared to control mice. Most importantly, LentiVIP delivery in DIO animal model of T2DM resulted in improved insulin sensitivity, glucose tolerance and protection against STZ-induced diabetes in addition to reduction in serum triglyceride/cholesterol levels. Collectively, these data suggest LentiVIP delivery should be evaluated as an experimental therapeutic approach for the treatment of T2DM.


Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 2/terapia , Peptídeo Intestinal Vasoativo/genética , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta Hiperlipídica , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Glucose/metabolismo , Intolerância à Glucose , Células Hep G2 , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Lentivirus/genética , Lentivirus/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Peptídeo Intestinal Vasoativo/administração & dosagem , Peptídeo Intestinal Vasoativo/biossíntese
10.
Hum Gene Ther ; 29(7): 802-815, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29409356

RESUMO

Postprandial glucose-induced insulin secretion from the islets of Langerhans is facilitated by glucagon-like peptide-1 (GLP-1)-a metabolic hormone with insulinotropic properties. Among the variety of effects it mediates, GLP-1 induces delta cell secretion of somatostatin, inhibits alpha cell release of glucagon, reduces gastric emptying, and slows food intake. These events collectively contribute to weight loss over time. During type 2 diabetes (T2DM), however, the incretin response to glucose is reduced and accompanied by a moderate reduction in GLP-1 secretion. To compensate for the reduced incretin effect, a human immunodeficiency virus-based lentiviral vector was generated to deliver DNA encoding human GLP-1 (LentiGLP-1), and the anti-diabetic efficacy of LentiGLP-1 was tested in a high-fat diet/streptozotocin-induced model of T2DM. Therapeutic administration of LentiGLP-1 reduced blood glucose levels in obese diabetic Sprague Dawley rats, along with improving insulin sensitivity and glucose tolerance. Normoglycemia was correlated with increased blood GLP-1 and pancreatic beta cell regeneration in LentiGLP-1-treated rats. Plasma triglyceride levels were also normalized after LentiGLP-1 injection. Collectively, these data suggest the clinical potential of GLP-1 gene transfer therapy for the treatment of T2DM.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Terapia Genética , Peptídeo 1 Semelhante ao Glucagon/genética , Glucose/metabolismo , Animais , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Modelos Animais de Doenças , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Humanos , Incretinas/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Lentivirus/genética , Obesidade/genética , Obesidade/patologia , Ratos
11.
Anticancer Agents Med Chem ; 15(1): 99-106, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25173558

RESUMO

The most common solid tumor is testicular cancer among young men. Bleomycin is an antitumor antibiotic used for the therapy of testicular cancer. TRAIL is a proapoptotic cytokine that qualified as an apoptosis inducer in cancer cells. Killing cancer cells selectively via apoptosis induction is an encouraging therapeutic strategy in clinical settings. Combination of TRAIL with chemotherapeutics has been reported to enhance TRAIL-mediated apoptosis of different kinds of cancer cell lines. The molecular ground for sensitization of tumour cells to TRAIL by chemotherapeutics might involve upregulation of TRAIL-R1 (TR/1, DR4) and/or TRAIL-R2 (TR/2, DR5) receptors or activation of proapoptotic proteins including caspases. The curative potential of TRAIL to eradicate cancer cells selectively in testicular cancer has not been studied before. In this study, we investigated apoptotic effects of bleomycin, TRAIL, and their combined application in NTera-2 and NCCIT testicular cancer cell lines. We measured caspase 3 levels as an apoptosis indicator, and TRAIL receptor expressions using flow cytometry. Both NTera-2 and NCCIT cells were fairly resistant to TRAIL's apoptotic effect. Incubation of bleomycin alone caused a significant increase in caspase 3 activity in NCCIT. Combined incubation with bleomycin and TRAIL lead to elevated caspase 3 activity in Ntera-2. Exposure to 72 h of bleomycin increased TR/1, TR/2, and TR/3 cell-surface expressions in NTera-2. Elevation in TR/1 cell-surface expression was evident only at 24 h of bleomycin application in NCCIT. It can be concluded that TRAIL death receptor expressions in particular are increased in testicular cancer cells via bleomycin treatment, and TRAIL-induced apoptosis is initiated.


Assuntos
Apoptose/efeitos dos fármacos , Bleomicina/farmacologia , Receptores de Morte Celular/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética , Neoplasias Testiculares/tratamento farmacológico , Regulação para Cima/efeitos dos fármacos , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Caspase 3/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Neoplasias Testiculares/genética , Regulação para Cima/genética
12.
Diabetes Metab Res Rev ; 30(5): 354-71, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24989141

RESUMO

Therapies targeting the action of incretin hormones have been under close scrutiny in recent years. The incretin effect has been defined as postprandial enhancement of insulin secretion by gut-derived factors. Likewise, incretin mimetics and incretin effect amplifiers are the two different incretin-based treatment strategies developed for the treatment of diabetes. Although, incretin mimetics produce effects very similar to those of natural incretin hormones, incretin effect amplifiers act by inhibiting dipeptidyl peptidase-4 (DPP-4) enzyme to increase plasma concentration of incretins and their biologic effects. Because glucagon-like peptide-1 (GLP-1) is an incretin hormone with various anti-diabetic actions including stimulation of glucose-induced insulin secretion, inhibition of glucagon secretion, hepatic glucose production and gastric emptying, it has been evaluated as a novel therapeutic agent for the treatment of type 2 diabetes mellitus (T2DM). GLP-1 also manifests trophic effects on pancreas such as pancreatic beta cell growth and differentiation. Because DPP-4 is the enzyme responsible for the inactivation of GLP-1, DPP-4 inhibition represents another potential strategy to increase plasma concentration of GLP-1 to enhance the incretin effect. Thus, anti-diabetic properties of these two classes of drugs have stimulated substantial clinical interest in the potential of incretin-based therapeutic agents as a means to control glucose homeostasis in T2DM patients. Despite this fact, clinical use of GLP-1 mimetics and DPP-4 inhibitors have raised substantial concerns owing to possible side effects of the treatments involving increased risk for pancreatitis, and C-cell adenoma/carcinoma. Thus, controversial issues in incretin-based therapies under development are reviewed and discussed in this manuscript.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Hipoglicemiantes/uso terapêutico , Incretinas/fisiologia , Incretinas/uso terapêutico , Animais , Diabetes Mellitus Tipo 2/fisiopatologia , Dipeptidil Peptidase 4/metabolismo , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Exenatida , Polipeptídeo Inibidor Gástrico/biossíntese , Polipeptídeo Inibidor Gástrico/fisiologia , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Hemoglobinas Glicadas/metabolismo , Humanos , Incretinas/efeitos adversos , Insulina/metabolismo , Insulina Glargina , Secreção de Insulina , Insulina de Ação Prolongada/uso terapêutico , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/fisiologia , Peptídeos/uso terapêutico , Receptores de Glucagon/agonistas , Receptores de Glucagon/efeitos dos fármacos , Peçonhas/uso terapêutico
13.
Expert Rev Mol Med ; 16: e7, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24666581

RESUMO

Glucagon-like peptide (GLP)-1 is an incretin hormone with several antidiabetic functions including stimulation of glucose-dependent insulin secretion, increase in insulin gene expression and beta-cell survival. Despite the initial technical difficulties and profound inefficiency of direct gene transfer into the pancreas that seriously restricted in vivo gene transfer experiments with GLP-1, recent exploitation of various routes of gene delivery and alternative means of gene transfer has permitted the detailed assessment of the therapeutic efficacy of GLP-1 in animal models of type 2 diabetes (T2DM). As a result, many clinical benefits of GLP-1 peptide/analogues observed in clinical trials involving induction of glucose tolerance, reduction of hyperglycaemia, suppression of appetite and food intake linked to weight loss have been replicated in animal models using gene therapy. Furthermore, GLP-1-centered gene therapy not only improved insulin sensitivity, but also reduced abdominal and/or hepatic fat associated with obesity-induced T2DM with drastic alterations in adipokine profiles in treated subjects. Thus, a comprehensive assessment of recent GLP-1-mediated gene therapy approaches with detailed analysis of current hurdles and resolutions, is discussed.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Peptídeo 1 Semelhante ao Glucagon/genética , Adenoviridae/genética , Animais , Dependovirus/genética , Terapia Genética , Vetores Genéticos , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Humanos , Pâncreas/metabolismo , Pâncreas/patologia , Regiões Promotoras Genéticas , Integração Viral
14.
Islets ; 5(2): 67-78, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23584214

RESUMO

Diabetes is a pandemic disease characterized by autoimmune, genetic and metabolic abnormalities. While insulin deficiency manifested as hyperglycemia is a common sequel of both Type-1 and Type-2 diabetes (T1DM and T2DM), it does not result from a single genetic defect--rather insulin deficiency results from the functional loss of pancreatic ß cells due to multifactorial mechanisms. Since pancreatic ß cells of patients with T1DM are destroyed by autoimmune reaction, these patients require daily insulin injections. Insulin resistance followed by ß cell dysfunction and ß cell loss is the characteristics of T2DM. Therefore, most patients with T2DM will require insulin treatment due to eventual loss of insulin secretion. Despite the evidence of early insulin treatment lowering macrovascular (coronary artery disease, peripheral arterial disease and stroke) and microvascular (diabetic nephropathy, neuropathy and retinopathy) complications of T2DM, controversy exists among physicians on how to initiate and intensify insulin therapy. The slow acting nature of regular human insulin makes its use ineffective in counteracting postprandial hyperglycemia. Instead, recombinant insulin analogs have been generated with a variable degree of specificity and action. Due to the metabolic variability among individuals, optimum blood glucose management is a formidable task to accomplish despite the presence of novel insulin analogs. In this article, we present a recent update on insulin analog structure and function with an overview of the evidence on the various insulin regimens clinically used to treat diabetes.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/prevenção & controle , Medicina Baseada em Evidências , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Animais , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Monitoramento de Medicamentos , Humanos , Hiperglicemia/prevenção & controle , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Insulina/administração & dosagem , Insulina/análogos & derivados , Insulina/metabolismo , Insulina Regular Humana/administração & dosagem , Insulina Regular Humana/análogos & derivados , Insulina Regular Humana/genética , Insulina Regular Humana/uso terapêutico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Proteínas Recombinantes/uso terapêutico
15.
Expert Rev Mol Med ; 14: e18, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23062285

RESUMO

Despite the fact that insulin injection can protect diabetic patients from developing diabetes-related complications, recent meta-analyses indicate that rapid and long-acting insulin analogues only provide a limited benefit compared with conventional insulin regarding glycemic control. As insulin deficiency is the main sequel of type-1 diabetes (T1D), transfer of the insulin gene-by-gene therapy is becoming an attractive treatment modality even though T1D is not caused by a single genetic defect. In contrast to human insulin and insulin analogues, insulin gene therapy targets to supplement patients not only with insulin but also with C-peptide. So far, insulin gene therapy has had limited success because of delayed and/or transient gene expression. Sustained insulin gene expression is now feasible using current gene-therapy vectors providing patients with basal insulin coverage, but management of postprandial hyperglycaemia is still difficult to accomplish because of the inability to properly control insulin secretion. Enteroendocrine cells of the gastrointestinal track (K cells and L cells) may be ideal targets for insulin gene therapy, but cell-targeting difficulties have limited practical implementation of insulin gene therapy for diabetes treatment. Therefore, recent gene transfer technologies developed to generate authentic beta cells through transdifferentiation are also highlighted in this review.


Assuntos
Diabetes Mellitus Tipo 1/genética , Terapia Genética , Células Secretoras de Insulina/metabolismo , Insulina/genética , Diabetes Mellitus Tipo 1/terapia , Regulação da Expressão Gênica , Humanos , Insulina/metabolismo
16.
J Mol Endocrinol ; 49(3): R157-67, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22991228

RESUMO

Type 2 diabetes (T2D) is characterized by chronic insulin resistance and a progressive decline in beta-cell function. Although rigorous glucose control can reduce morbidity and mortality associated with diabetes, achieving optimal long-term glycemic control remains to be accomplished in many diabetic patients. As beta-cell mass and function inevitably decline in T2D, exogenous insulin administration is almost unavoidable as a final outcome despite the use of oral antihyperglycemic agents in many diabetic patients. Pancreatic islet cell death, but not the defect in new islet formation or beta-cell replication, has been blamed for the decrease in beta-cell mass observed in T2D patients. Thus, therapeutic approaches designed to protect islet cells from apoptosis could significantly improve the management of T2D, because of its potential to reverse diabetes not just ameliorate glycemia. Therefore, an ideal beta-cell-preserving agent is expected to protect beta cells from apoptosis and stimulate postprandial insulin secretion along with increasing beta-cell replication and/or islet neogenesis. One such potential agent, the islet endocrine neuropeptide vasoactive intestinal peptide (VIP) strongly stimulates postprandial insulin secretion. Because of its broad spectrum of biological functions such as acting as a potent anti-inflammatory factor through suppression of Th1 immune response, and induction of immune tolerance via regulatory T cells, VIP has emerged as a promising therapeutic agent for the treatment of many autoimmune diseases including diabetes.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/uso terapêutico , Peptídeo Intestinal Vasoativo/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo
17.
BMC Cancer ; 12: 58, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22313795

RESUMO

BACKGROUND: Colorectal cancer is the third most common cancer and the third leading cause of cancer-related death. Bevacizumab is a humanized monoclonal antibody developed against vascular endothelial growth factor (VEGF) for the treatment of metastatic cancer. The parameters of RECIST (Response Evaluation Criteria for Solid Tumors) are not adequate to detect important treatment effects and response. Our goal was to evaluate the possibility of using sTRAIL (serum-soluble TNF-related apoptosis-inducing ligand) and VEGF as markers of treatment efficacy and prognosis in patients with metastatic colon cancer. METHODS: sTRAIL and VEGF levels were measured by ELISA in the sera of 16 bevacizumab-treated metastatic colon cancer patients and 10 presumably healthy age-matched controls. The measurements were taken before and after treatment for comparison purposes. RESULTS: Elevated levels of sTRAIL were found in seven out of 16 patients after bevacizumab treatment. Although these patients had a median survival time of 20.6 months, the remaining bevacizumab-treated patients who did not show an increase in sTRAIL had a median survival time of 9.4 months. As expected, serum VEGF levels were decreased in all patients who received bevacizumab therapy and showed no correlation between serum VEGF levels and patient survival (data not shown). CONCLUSIONS: Serum sTRAIL levels might be a useful predictor of prognosis in metastatic colon cancer, in the early evaluation stages following bevacizumab treatment.


Assuntos
Adenoma/diagnóstico , Biomarcadores Tumorais/sangue , Neoplasias do Colo/diagnóstico , Ligante Indutor de Apoptose Relacionado a TNF/sangue , Adenoma/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Bevacizumab , Neoplasias do Colo/tratamento farmacológico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular/sangue
18.
Exp Diabetes Res ; 2011: 625813, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22144989

RESUMO

TNF-related apoptosis-inducing ligand (TRAIL) is an important component of the immune system. Although it is well acknowledged that it also has an important role in Type 1 Diabetes (T1D) development, this presumed role has not yet been clearly revealed. Streptozotocin (STZ) and Cyclophosphamide (CY) are frequently used agents for establishment or acceleration of T1D disease in experimental models, including the non-obese diabetic (NOD) mice. Although such disease models are very suitable for diabetes research, different expression patterns for various T1D-related molecules may be expected, depending on the action mechanism of the applied agent. We accelerated diabetes in female NOD mice using STZ or CY and analyzed the expression profiles of TRAIL ligand and receptors throughout disease development. TRAIL ligand expression followed a completely different pattern in STZ- versus CY-accelerated disease, displaying a prominent increase in the former, while appearing at reduced levels in the latter. Decoy receptor 1 (DcR1) expression also increased significantly in the pancreatic islets in STZ-induced disease. Specific increases observed in TRAIL ligand and DcR1 expressions may be part of a defensive strategy of the beta islets against the infiltrating leukocytes, while the immune-suppressive agent CY may partly hold down this defense, contributing further to diabetes development.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Ilhotas Pancreáticas/metabolismo , Membro 10c de Receptores do Fator de Necrose Tumoral/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Animais , Ciclofosfamida/toxicidade , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/patologia , Feminino , Imuno-Histoquímica , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/patologia , Camundongos , Camundongos Endogâmicos NOD , Estreptozocina/toxicidade
19.
Head Neck ; 33(9): 1278-84, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21837697

RESUMO

BACKGROUND: Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a death ligand currently under clinical trials for cancer. The molecular profile of TRAIL and TRAIL receptors has not yet been mapped for patients with laryngeal squamous cell carcinoma (SCC) or patients with oral cavity squamous cell carcinoma (OCSCC). METHODS: Paraffin-embedded tissues from 60 patients with laryngeal SCC and 14 patients with OCSCC were retrospectively analyzed using immunohistochemistry. RESULTS: An increase in decoy-R1 (DcR1) but a decrease in decoy-R2 (DcR2) expression were observed in patients with laryngeal SCC and in patients with OCSCC compared with control individuals with benign lesions. Clinical and pathologic grading revealed distinctive TRAIL and TRAIL receptor profiles in patients with squamous cell carcinoma of the head and neck (SCCHN). CONCLUSIONS: TRAIL and a TRAIL receptor expression profile might be useful to follow-up disease progression by virtue of its connection with clinical staging and pathologic grading in patients with laryngeal SCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Laríngeas/metabolismo , Neoplasias Bucais/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Laríngeas/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Estudos Retrospectivos
20.
Diabetes Metab Res Rev ; 27(6): 575-83, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21584921

RESUMO

BACKGROUND: To increase the success rate in xenogeneic islet transplantation, proper assessment of graft mass is required following transplantation. For this reason, we aimed to develop a suitable fluorescence imaging system to monitor islet xenograft survival in diabetic mice. METHODS: Adenovirus vector encoding enhanced green fluorescent protein-transduced rat pancreatic islets were transplanted under the renal capsule of streptozotocin-induced diabetic mice and the fluorescence signal was quantified over time using a cooled charge-coupled device. Non-fasting blood glucose levels were recorded during the same period. Insulin release from transduced and control islets was detected via enzyme-linked immunosorbent assay. RESULTS: Adenovirus vector encoding enhanced green fluorescent protein infection did not alter the function or survival of pancreatic islets post transduction. A direct correlation was found between the number of islets (250-750) transplanted under the kidney capsule and the blood glucose recovery. CONCLUSIONS: Fluorescence imaging appears to be a useful tool for quantitative assessment of islet cell viability post transplantation and could permit earlier detection of graft rejection.


Assuntos
Sobrevivência de Enxerto/fisiologia , Proteínas de Fluorescência Verde , Transplante das Ilhotas Pancreáticas/métodos , Transplante Heterólogo , Adenoviridae/genética , Animais , Glicemia/metabolismo , Sobrevivência Celular , Diabetes Mellitus Experimental , Feminino , Fluorescência , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Wistar
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