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1.
Exp Eye Res ; 215: 108901, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34933001

RESUMO

The purpose of this study was to evaluate the neuroprotective effects of omega-3 polyunsaturated fatty acid (ω3-PUFA) supplementation in a mouse model of OPA1-associated autosomal dominant optic atrophy (ADOA). The blood level of arachidonic acid (AA) and eicosapentaenoic acid (EPA) served to adjust the treatment dosage (AA/EPA = 1.0-1.5). Eight-month-old mice were allocated to four groups (n = 20/group): the ω3-PUFA-treated Opa1enu/+, untreated Opa1enu/+, ω3-PUFA-treated wild-type and untreated wild-type groups. Treated mice received the ω3-PUFAs, EPA and docosahexaenoic acid (DHA; 5:1 ratio) by daily gavage for 4 months based on the measured AA/EPA ratio. Blood, retina and optic nerve (ON) fatty acid levels were determined by gas chromatography, and the retina and ON were histologically examined. Western blotting and/or immunohistochemistry was performed to analyse retinal mediators involved in Opa1-mutation-mediated apoptosis, inflammation and oxidative stress. Increased EPA and reduced AA levels were primarily observed predominantly in the blood and retinal tissues, and a similarly high EPA level tended to be observed in the ONs of ω3-PUFA-treated mice. Retinal ganglion cell and ON axonal densities were higher in both mouse strains upon ω3-PUFA treatment than in the corresponding untreated groups. Caspase-3 expression analysis showed fewer apoptotic retinal cells in both groups of treated mice. Decreases in inflammatory microglia and astrocytes activation and proapoptotic Bcl-2-associated X protein (Bax) expression were noted in the treated groups, with no difference in the antioxidant superoxide dismutase-2 expression. ω3-PUFA supplementation had neuroprotective effects on the retinas of Opa1enu/+ and wild-type mice via blockade of microglia and astrocytes activation and suppression of Bax and caspase-3. Our findings indicated that inhibition of oxidative stress may not be involved in ω3-PUFA-mediated neuroprotection. These novel findings support the use of ω3-PUFAs as a beneficial therapy in the occurrence of ADOA, posing the basis for future clinical trials to confirm these observations.


Assuntos
Ácidos Graxos Ômega-3 , Neuroglia , Fármacos Neuroprotetores , Atrofia Óptica Autossômica Dominante , Animais , Apoptose , Ácido Araquidônico/metabolismo , Caspase 3/metabolismo , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Ácidos Graxos Ômega-3/farmacologia , GTP Fosfo-Hidrolases/metabolismo , Camundongos , Neuroglia/metabolismo , Neuroglia/patologia , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Atrofia Óptica Autossômica Dominante/tratamento farmacológico , Atrofia Óptica Autossômica Dominante/genética , Atrofia Óptica Autossômica Dominante/metabolismo , Atrofia Óptica Autossômica Dominante/patologia , Retina/metabolismo , Proteína X Associada a bcl-2/metabolismo
2.
BMJ Open Ophthalmol ; 4(1): e000326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799410

RESUMO

OBJECTIVE: To evaluate the therapeutic effects of omega-3 (ω3) fatty acids in the retina of aged mice when the blood arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio is maintained between 1.0 and 1.5. METHODS AND ANALYSIS: Aged (24-month-old) wild-type C57BL/6J mice were allocated to two groups: ω3 treated and untreated. Treatment with ω3 was by daily gavage administration of EPA and docosahexaenoic acid for 60 days. Gas chromatography was used to identify and quantify fatty acids in the blood and retina. To count lipofuscin granules and measure the photoreceptor layer, eyecups were examined histologically using transmission electron microscopy and light microscopy. We also analysed eyecups using mass spectrometry-based proteomics. RESULTS: AA levels were lower, and EPA levels were higher, in the blood and retinas of the ω3-treated group than in the untreated group, resulting in a lower AA/EPA ratio. The ω3-treated group also showed significantly fewer lipofuscin granules and a thicker outer nuclear layer than the untreated group. Proteomic analysis revealed significantly greater expression of myelin basic protein, myelin regulatory factor-like protein, myelin proteolipid protein and glial fibrillar acidic protein in the ω3-treated group than in the untreated group. Three different pathways were significantly affected by ω3 treatment: fatty acid elongation, biosynthesis of unsaturated fatty acids and metabolic pathways. CONCLUSION: Two months of ω3 supplementation (when the blood AA/EPA~1.0-1.5) in aged mice reduced lipofuscin granule formation in the retina and protected the photoreceptor layer, suggesting that ω3 supplementation slows normal age-related retinal degeneration.

3.
Invest Ophthalmol Vis Sci ; 59(7): 2757-2767, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860462

RESUMO

Purpose: To evaluate the therapeutic effects of omega-3 (ω3) fatty acids on retinal degeneration in the ABCA4-/- model of Stargardt disease when the blood level of arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio is between 1 and 1.5. Methods: Eight-month-old mice were allocated to three groups: wild type (129S1), ABCA4-/- untreated, and ABCA4-/- ω3 treated. ω3 treatment lasted 3 months and comprised daily gavage administration of EPA and docosahexaenoic acid (DHA). Blood and retinal fatty acid analysis was performed using gas chromatography to adjust the blood AA/EPA ∼1 to 1.5. Eyecups were histologically examined using transmission electron microscopy and confocal microscopy to evaluate lipofuscin granules and the photoreceptor layer. Retinal N-retinylidene-N-retinylethanolamine (A2E), a major component of retinal pigment epithelium lipofuscin, was quantified using liquid chromatography and tandem mass spectrometry, in addition to retinal proteomic analysis to determine changes in inflammatory proteins. Results: EPA levels increased and AA levels decreased in the blood and retinas of the treatment group. Significantly less A2E and lipofuscin granules were observed in the treatment group. The thickness of the outer nuclear layer was significantly greater in the treatment group (75.66 ± 4.80 µm) than in the wild-type (61.40 ± 1.84 µm) or untreated ABCA4-/- (56.50 ± 3.24 µm) groups. Proteomic analysis indicated lower levels of complement component 3 (C3) in the treatment group, indicative of lower complement-induced inflammatory response. Conclusions: Three months of ω3 supplementation (AA/EPA ∼1-1.5) reduces A2E levels, lipofuscin granules, and C3 levels in the ABCA4-/- mouse model of Stargardt disease, consistent with slowing of the disease.


Assuntos
Modelos Animais de Doenças , Ácidos Graxos Ômega-3/uso terapêutico , Degeneração Macular/congênito , Transportadores de Cassetes de Ligação de ATP/genética , Administração Oral , Animais , Cromatografia Gasosa , Complemento C3/metabolismo , Córnea/metabolismo , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Cristalino/metabolismo , Lipofuscina/metabolismo , Degeneração Macular/tratamento farmacológico , Degeneração Macular/genética , Degeneração Macular/metabolismo , Degeneração Macular/patologia , Masculino , Camundongos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Retina/metabolismo , Retinoides/metabolismo , Doença de Stargardt , Espectrometria de Massas em Tandem
4.
BMC Cancer ; 12: 113, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22443862

RESUMO

BACKGROUND: Diet has long been suspected to impact on breast cancer risk. In this study we evaluated whether the degree of adherence to a Mediterranean diet pattern modifies breast cancer risk amongst Greek-Cypriot women. METHODS: Subjects included 935 cases and 817 controls, all participating in the MASTOS case-control study in Cyprus. The study was approved by the Cyprus National Bioethics Committee. Information on dietary intakes was collected using an interviewer administered 32-item Food Frequency Questionnaire. Information on demographic, anthropometric, lifestyle, and other confounding factors was also collected. Adherence to the Mediterranean Diet pattern was assessed using two a-priory defined diet scores. In addition, dietary patterns specific to our population were derived using Principal Component Analysis (PCA). Logistic regression models were used to assess the association between the dietary patters and breast cancer risk. RESULTS: There was no association with breast cancer risk for either score, however, higher consumptions of vegetables, fish and olive oil, were independently associated with decreased risk. In addition, the PCA derived component which included vegetables, fruit, fish and legumes was shown to significantly reduce risk of breast cancer (ORs across quartiles of increasing levels of consumption: 0.89 95%CI: 0.65-1.22, 0.64 95%CI: 0.47-0.88, 0.67 95%CI: 0.49-0.92, P trend < 0.0001), even after adjustment for relevant confounders. CONCLUSIONS: Our results suggest that adherence to a diet pattern rich in vegetables, fish, legumes and olive oil may favorably influence the risk of breast cancer. This study is the first investigation of dietary effects on breast cancer risk in Cyprus, a country whose population has traditionally adhered to the Mediterranean diet.


Assuntos
Neoplasias da Mama/etiologia , Dieta Mediterrânea , Comportamento Alimentar , Adulto , Idoso , Estudos de Casos e Controles , Chipre , Feminino , Produtos Pesqueiros , Humanos , Pessoa de Meia-Idade , Azeite de Oliva , Óleos de Plantas , Medição de Risco/métodos , Fatores de Risco , Verduras
5.
Hemoglobin ; 32(1-2): 17-28, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18274979

RESUMO

Cardiac damage caused by iron overload toxicity is the main cause of death in thalassemia patients. Biopsy samples of poorly chelated thalassemia patients who suffered congestive cardiac failure (CCF) show extensive iron deposition in the myocardium. In one patient who survived CCF, a cardiac biopsy was performed during the removal of a thrombus caused by a port-a-cath, which was used for the administration of intravenous (iv) deferoxamine (DFO). Ultrastructural pathology studies of the cardiac biopsy indicated extensive iron deposition in myocytes with accumulation of iron mainly in lysosomes, leading in some cases to their disruption. Damage to other intracellular components of the myocytes and loss of myofibers was also observed. The patient became intolerant to iv and subcutaneous (sc) DFO 2 years after the CCF, and was then treated with deferiprone (L1) for 7 years. Within 1 year of L1 treatment at 75-80 mg/kg/day, serum ferritin levels were reduced to <0.45 mg/L and she became asymptomatic, needing no further drugs for her cardiomyopathy. Lowering the L1 dose to 50-70 mg/kg/day caused an increase in serum ferritin levels. Maintenance of normal iron stores during the last 3 years as detected by cardiac and liver magnetic resonance imaging (MRI) T2 and T2* and normalization of serum ferritin levels (<0.15 mg/L) was observed following L1 therapy at 80-85 mg/kg/day. Deferiprone (>80 mg/kg/day) appears to be effective in the rapid clearance of cardiac iron, in the reversal of iron overload related cardiomyopathy, in the maintenance of normal iron stores and the overall long-term survival of thalassemia patients.


Assuntos
Cardiomiopatias/tratamento farmacológico , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Piridonas/uso terapêutico , Talassemia/tratamento farmacológico , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Terapia por Quelação , Deferiprona , Desferroxamina/administração & dosagem , Feminino , Ferritinas/análise , Ferritinas/sangue , Humanos , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/etiologia , Imageamento por Ressonância Magnética , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Células Musculares/ultraestrutura , Miocárdio/patologia , Piridonas/administração & dosagem , Talassemia/complicações , Talassemia/patologia
6.
Muscle Nerve ; 31(2): 260-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15389648

RESUMO

We report a patient with late-onset celiac disease and neurological manifestations including myopathy, polyneuropathy, and ataxia. Laboratory investigations showed anti-gliadin antibodies and severe vitamin E deficiency. Muscle biopsy revealed inflammatory infiltrates and rimmed vacuoles, similar to those found in inclusion-body myositis. A gluten-free diet and vitamin E supplementation reversed both the clinical neurological manifestations and the abnormalities in the muscle biopsy. Anti-gliadin antibodies were no longer present. This case illustrates the spectrum of neurological complications of celiac disease and documents the occurrence of reversible pathology resembling inclusion-body myopathy in the muscle.


Assuntos
Doença Celíaca/dietoterapia , Miosite de Corpos de Inclusão/dietoterapia , Miosite/dietoterapia , Deficiência de Vitamina E/dietoterapia , Idoso , Doença Celíaca/complicações , Doença Celíaca/patologia , Glutens/efeitos adversos , Humanos , Masculino , Miosite/complicações , Miosite/patologia , Miosite de Corpos de Inclusão/complicações , Miosite de Corpos de Inclusão/patologia , Vitamina E/administração & dosagem , Deficiência de Vitamina E/complicações , Deficiência de Vitamina E/patologia
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