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1.
Drug Dev Res ; 83(3): 615-621, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34596893

RESUMO

Biological adjuvants that target the gut immune system are being developed for modulating the immune system. Hyperimmune bovine colostrum (HBC), produced by harvesting the bovine colostrum of dairy cows immunized to exogenous antigens, has been shown to modulate the immune responses and alleviate immune-mediated organ damages. The aim of the present study was to determine the ability of HBC to promote antiviral interferonγ (IFNγ) T cell responses. In a preclinical study, mice were orally administered with HBC for 5 days and tested for the number of T cell clones secreting IFNγ in response to viral antigens of the swine flu, New Caledonia influenza, and cytomegalovirus. In a phase I/IIa clinical trial, five healthy volunteers were treated for 5 days with HBC followed by testing the anti-coronavirus disease (COVID-19) immunity. In the preclinical study, oral administration of HBC augmented the number of T cell clones secreting IFNγ in response to viral antigens. In the clinical trial, oral administration of HBC to healthy males significantly increased the number of anti-COVID-19 spike protein IFNγ positive T cell clones. Oral administration of HBC provides a novel method for augmenting antiviral responses. Its high-safety profile makes it ideal for all disease stages and for pre-emptive therapy among medical personnel and other workers who are at a high risk of exposure to infections. The relatively low cost of HBC is expected to minimize care provider burdens, costs, and enable its global application.


Assuntos
COVID-19 , Colostro , Administração Oral , Animais , Antígenos Virais , Antivirais/farmacologia , Antivirais/uso terapêutico , Bovinos , Feminino , Humanos , Fatores Imunológicos , Interferon gama , Masculino , Camundongos , Gravidez , Linfócitos T
2.
Obes Rev ; 22(2): e13108, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32720402

RESUMO

Adropin is a peptide hormone, which plays a role in energy homeostasis and controls glucose and fatty acid metabolism. Its levels correlate with changes in carbohydrate-lipid metabolism, metabolic diseases, central nervous system function, endothelial function and cardiovascular disease. Both metabolic pathways and adropin are regulated by the circadian clocks. Here, we review the roles of the autonomic nervous system and circadian rhythms in regulating metabolic pathways and energy homeostasis. The beneficial effects of chronotherapy in various systems are discussed. We suggest a potential role for adropin as a mediator of the metabolic system-autonomic nervous system axis. We discuss the possibility of establishing an individualized adropin and circadian rhythm-based platform for implementing chronotherapy, and variability signatures for improving the efficacy of adropin-based therapies are discussed.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Cronoterapia , Relógios Circadianos , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Humanos
3.
J Med Food ; 20(5): 458-464, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28387617

RESUMO

ß-glucosylceramide (GC) is a naturally occurring glycosphingolipid that was shown to improve hepatic steatosis, steatohepatitis, and insulin resistance in animal models of nonalcoholic fatty liver disease. In this study, we evaluated the safety and efficacy of oral administration of GC in subjects with nonalcoholic steatohepatitis (NASH). Twenty-three patients with biopsy proven NASH were enrolled in a double-blind, placebo-controlled trial. Patients were orally administered daily with 7.5 mg of GC. Patients were followed for safety, liver enzymes, HbA1c, insulin sensitivity, lipid profile, hepatic fat content as measured by magnetic resonance imaging (MRI), and NASH score on liver biopsy. No treatment-related adverse events were observed during treatment. In a per protocol analysis of data, oral administration of GC decreased the hepatic fat content as measured by MRI in GC-treated compared with placebo. HbA1C decreased in patients treated with GC. GC treatment was associated with a milder decrease in the high-density lipoprotein serum levels. The beneficial effects were associated with a decrease in CD4 and NKT cell subsets of lymphocytes. Due to the small number of subjects enrolled, differences did reach statistical significance. Oral administration of GC is safe and biologically active in patients with NASH and insulin resistance.


Assuntos
Glucosilceramidas/administração & dosagem , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Administração Oral , Adulto , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/metabolismo , Lipoproteínas HDL/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/metabolismo , Adulto Jovem
4.
Am J Physiol Endocrinol Metab ; 306(6): E648-57, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24425765

RESUMO

A high-sucrose, low-copper-diet (HSD) induces inhibition of glucose-sensitive rats (CDs) but not Cohen diabetes-resistant rats (CDr). Copper-supplemented HSD increased activity of the copper-dependent mitochondrial respiratory chain enzyme cytochrome c oxidase (COX) and reversed hyperglycemia. This study examined the mechanism by which interleukin-1ß modulates GSIS and the role of COX in this process. We measured COX activity, ATP content, GSIS, iNOS expression, and nitrite production with and without IL-1ß, N(ω)-nitro-l-arginine, copper, or potassium cyanide in isolated islets of CDs and CDr fed different diets. We found reduced COX activity, ATP content, and GSIS in isolated islets of CDs rats fed a regular diet. These were severely reduced following HSD and were restored to regular diet levels on copper-supplemented HSD (P < 0.01 vs. CDr islets). Potassium cyanide chemically reduced COX activity, decreasing GSIS and thus reinforcing the link between islet COX activity and GSIS. Interleukin-1ß (2.5 U/ml) reduced GSIS and COX activity in CDs islets. Exposure to 10 U/ml interleukin-1ß decreased GSIS and COX activity in both CDs and CDr islets, inducing a similar nitrite production. Nevertheless, the effect on GSIS was more marked in CDs islets. A significant iNOS expression was detected in CDs on the HSD diet, which was reduced by copper supplementation. N(ω)-nitro-l-arginine and copper prevented the deleterious effect of interleukin-1ß on COX activity and GSIS. We conclude that reduced islet COX activity renders vulnerability to GSIS inhibition on low-copper HSD through two interrelated pathways: 1) by further reducing the activity of COX that is essential for ß-cell ATP-production and insulin secretion and 2) by inducing the expression of iNOS and nitric oxide-mediated COX inhibition. We suggest that islet COX activity must be maintained above a critical threshold to sustain adequate GSIS with exposure to low-copper HSD.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Insulina/metabolismo , Interleucina-1beta/metabolismo , Ilhotas Pancreáticas/metabolismo , Óxido Nítrico/metabolismo , Animais , Cobre/deficiência , Cobre/metabolismo , Cobre/uso terapêutico , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Sacarose Alimentar/efeitos adversos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Inibidores Enzimáticos/farmacologia , Glucose/metabolismo , Hiperglicemia/metabolismo , Hiperglicemia/prevenção & controle , Resistência à Insulina , Secreção de Insulina , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Concentração Osmolar , Ratos , Ratos Endogâmicos , Técnicas de Cultura de Tecidos
5.
Am J Physiol Endocrinol Metab ; 304(10): E1023-34, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23512809

RESUMO

ß-Cell mitochondrial dysfunction as well as proinflammatory cytokines have been suggested to contribute to reduced glucose-stimulated insulin secretion (GSIS) in type 2 diabetes. We recently demonstrated that Cohen diabetic sensitive (CDs) rats fed a high-sucrose, low-copper diet (HSD) developed hyperglycemia and reduced GSIS in association with peri-islet infiltration of fat and interleukin (IL)-1ß-expressing macrophages, whereas CD resistant (CDr) rats remained normoglycemic on HSD. We examined: 1) the correlation between copper concentration in the HSD and progression, prevention, and reversion of hyperglycemia in CDs rats, 2) the relationship between activity of the copper-dependent, respiratory-chain enzyme cytochrome c oxidase (COX), infiltration of fat, IL-1ß-expressing macrophages, and defective GSIS in hyperglycemic CDs rats. CDs and CDr rats were fed HSD or copper-supplemented HSD before and during hyperglycemia development. Blood glucose and insulin concentrations were measured during glucose tolerance tests. Macrophage infiltration and IL-1ß expression were evaluated in pancreatic sections by electron-microscopy and immunostaining. COX activity was measured in pancreatic sections and isolated islets. In CDs rats fed HSD, GSIS and islet COX activity decreased, while blood glucose and infiltration of fat and IL-1ß-expressing macrophages increased with time on HSD (P < 0.01 vs. CDr-HSD rats, all parameters, respectively). CDs rats maintained on copper-supplemented HSD did not develop hyperglycemia, and in hyperglycemic CDs rats, copper supplementation restored GSIS and COX activity, reversed hyperglycemia and infiltration of fat and IL-1ß-expressing macrophages (P < 0.01 vs. hyperglycemic CDs-HSD rats, all parameters, respectively). We provide novel evidence for a critical role of low dietary copper in diminished GSIS of susceptible CDs rats involving the combined consequence of reduced islet COX activity and pancreatic low-grade inflammation.


Assuntos
Cobre/administração & dosagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Mitocôndrias/efeitos dos fármacos , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Suplementos Nutricionais , Ácidos Graxos não Esterificados/metabolismo , Teste de Tolerância a Glucose , Hiperglicemia/enzimologia , Hiperglicemia/metabolismo , Hiperglicemia/prevenção & controle , Imuno-Histoquímica , Insulina/sangue , Secreção de Insulina , Células Secretoras de Insulina/enzimologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/ultraestrutura , Interleucina-1beta/metabolismo , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Ratos , Triglicerídeos/metabolismo
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