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1.
Invest Ophthalmol Vis Sci ; 47(12): 5227-33, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17122107

RESUMO

PURPOSE: To examine the dose-response relationship between oral lutein supplementation and serum lutein concentrations in persons aged 60 years and older, with or without age-related macular degeneration (AMD). METHODS: Forty-five participants with no AMD, large drusen, or advanced AMD, were randomized to receive one of three doses (2.5, 5, or 10 mg) of lutein for 6 months and to be observed for 6 additional months after the cessation of lutein supplementation. RESULTS: The mean age of the participants (33 women) was 71 years (range: 60-91). The serum lutein concentrations of each dose group were similar before supplementation, increased at 1 month, and peaked by 3 months. Median serum concentrations of the 2.5-, 5-, and 10-mg groups from baseline to month 6 increased from 18.7 to 35.1 microg/dL (2-fold increase), from 17.8 to 59.2 microg/dL (2.9-fold increase), and from 15.1 to 66.8 microg/dL (4-fold increase), respectively (all P < 0.001). The increases in lutein serum concentrations did not vary with AMD disease severity (P = 0.98). No toxicity was observed with any dose of lutein. No significant changes were detected in visual acuity or visual field tests. CONCLUSIONS: Increasing doses of lutein supplements significantly increased the serum levels of lutein and zeaxanthin, and doses up to 10 mg were safely administered. A long-term large clinical trial is necessary to investigate the safety and efficacy of lutein in reducing the risk of the development of advanced AMD.


Assuntos
Luteína/administração & dosagem , Degeneração Macular/sangue , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Comportamento Alimentar , Feminino , Humanos , Luteína/sangue , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Acuidade Visual , Campos Visuais , Xantofilas/sangue , Zeaxantinas
2.
Invest Ophthalmol Vis Sci ; 46(2): 655-62, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15671296

RESUMO

PURPOSE: To develop a local drug delivery system that provides therapeutic cyclosporine levels to treat lacrimal gland graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. METHODS: Episcleral cyclosporine implants were manufactured with a silicone-based matrix design, and in vitro release rates were determined. Preclinical evaluation included toxicology (clinical examination, serial electroretinography, and histopathology) in normal rabbits and dogs, pharmacokinetics in normal rabbits, and pharmacodynamics in a canine model of aqueous tear deficiency and keratoconjunctivitis sicca. RESULTS: The cyclosporine implants showed sustained release of drug over time with in vitro assays. Histopathology showed normal ocular tissues in both dogs and rabbits 6 months after implantation. The cyclosporine implant produced lacrimal gland drug levels 1 to 2 log units higher than those reported with a variety of topical cyclosporine formulations and oral administration. The cyclosporine implant was effective in a canine model of keratoconjunctivitis sicca, with all animals able to discontinue topical cyclosporine and maintain normal Schirmer scores over a 6-month follow-up. CONCLUSIONS: This preclinical evaluation showed that the episcleral cyclosporine implant was safe, delivered potentially therapeutic cyclosporine levels to the lacrimal gland, and showed efficacy in a clinically relevant model of keratoconjunctivitis sicca. The episcleral cyclosporine implant shows promise in reducing the morbidity associated with lacrimal gland graft-versus-host disease after allogeneic hematopoietic stem cell transplantation. In addition, continuous release of cyclosporine in the subconjunctival space with the episcleral implant was an effective means of delivering drug to the ocular surface and may have potential in treating other ocular inflammatory diseases.


Assuntos
Ciclosporina/farmacocinética , Olho/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Imunossupressores/farmacocinética , Esclera/metabolismo , Animais , Disponibilidade Biológica , Ciclosporina/farmacologia , Ciclosporina/toxicidade , Cães , Avaliação Pré-Clínica de Medicamentos , Implantes de Medicamento , Eletrorretinografia/efeitos dos fármacos , Olho/patologia , Feminino , Doença Enxerto-Hospedeiro/patologia , Imunossupressores/farmacologia , Imunossupressores/toxicidade , Ceratoconjuntivite/tratamento farmacológico , Ceratoconjuntivite/patologia , Masculino , Coelhos , Retina/efeitos dos fármacos , Segurança , Esclera/efeitos dos fármacos , Esclera/patologia
3.
Invest Ophthalmol Vis Sci ; 49(9): 3864-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18450596

RESUMO

PURPOSE: Increased dietary intake of lutein/zeaxanthin and omega-long-chain polyunsaturated fatty acids (omega-3 LCPUFA) was found to be associated with reduced risk of advanced age-related macular degeneration (AMD). The purpose of the study was to examine the effect of oral supplementation of omega-3 LCPUFA on changes in serum levels of lutein/zeaxanthin during supplementation in persons 60 years of age and older, with or without AMD. METHODS: Forty participants with AMD of various degrees of severity received lutein (10 mg) and zeaxanthin (2 mg) daily and were equally randomized to receive omega-3 LCPUFA (350 mg docosahexaenoic acid [DHA] and 650 mg eicosapentaenoic acid [EPA]) or placebo for 6 months. Serum levels of lutein, zeaxanthin, and omega-3 LCPUFAs and macular pigment optical densities were measured at baseline, 1 week, and 1, 3, 6, and 9 months. RESULTS: By month 6, the median serum levels of lutein/zeaxanthin increased by two- to threefold compared with baseline. Increases in serum levels of lutein/zeaxanthin did not differ by omega-3 LCPUFA treatment (P > 0.5). After 1 month, in the omega-3 LCPUFA-treated group, the median levels of DHA and EPA increased and the placebo group had no changes. At month 6, participants with AMD had a lower increase in serum lutein concentration than did those without AMD (P < 0.05). CONCLUSIONS: The addition of omega-3 LCPUFA to oral supplementation of lutein/zeaxanthin did not change the serum levels of lutein and zeaxanthin. A long-term large clinical trial is necessary to investigate the benefits and adverse effects of these factors for the treatment of AMD.


Assuntos
Ácidos Graxos Ômega-3/uso terapêutico , Luteína/sangue , Degeneração Macular/tratamento farmacológico , Acuidade Visual , Xantofilas/sangue , Idoso , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Valores de Referência , Fatores de Tempo , Zeaxantinas
4.
Retina ; 26(5): 523-30, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16770258

RESUMO

PURPOSE: The safety and pharmacokinetics of a triamcinolone acetonide (TA) preservative-free (TA-PF) formulation were investigated after intravitreal administration in rabbits. METHODS: A TA-PF formulation was prepared as a sterile 40-mg/mL or 160-mg/mL suspension in single-use vials by adding TA powder to 0.5% hydroxypropyl methylcellulose in normal saline. TA-PF (4-mg and 16-mg doses) and Kenalog (Bristol-Myers-Squibb, Princeton, NJ) (4-mg dose) were injected into the vitreous of separate groups of rabbits, and drug levels were measured in the vitreous over time with HPLC. Ocular toxicology (clinical examination, serial electroretinography, and histopathologic analysis) was evaluated in a separate group of animals after intravitreal TA-PF injection. RESULTS: The half-lives of the injection amount in the vitreous, 4-mg TA-PF, 16-mg TA-PF, and 4-mg Kenalog, were found to be 24 days, 39 days, and 23 days, respectively. There were no signs of toxicities by clinical examination after TA-PF injection. Serial electroretinograms of rabbits receiving either 4-mg or 16-mg intravitreal TA-PF injections remained normal over time. Histopathologic analysis showed normal ocular tissues in animals receiving either 4-mg or 16-mg intravitreal TA-PF injections. CONCLUSION: The half-life of TA in the vitreous after a 4-mg injection of either TA-PF or Kenalog was comparable. A 16-mg dose of TA-PF produced a long vitreous half-life, and this may be of clinical benefit in patients requiring 6 months of drug exposure in the eye for a chronic disease.


Assuntos
Glucocorticoides/farmacocinética , Triancinolona Acetonida/farmacocinética , Animais , Disponibilidade Biológica , Química Farmacêutica , Eletrorretinografia , Feminino , Glucocorticoides/toxicidade , Meia-Vida , Injeções , Masculino , Soluções Oftálmicas/farmacocinética , Soluções Oftálmicas/toxicidade , Conservantes Farmacêuticos , Coelhos , Retina/efeitos dos fármacos , Retina/patologia , Triancinolona Acetonida/toxicidade , Corpo Vítreo
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