Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
Pharmaceutics ; 15(6)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37376094

RESUMO

The purpose of this study was to determine corneal permeability and uptake in rabbit, porcine, and bovine corneas for twenty-five drugs using an N-in-1 (cassette) approach and relate these parameters to drug physicochemical properties and tissue thickness through quantitative structure permeability relationships (QSPRs). A twenty-five-drug cassette containing ß-blockers, NSAIDs, and corticosteroids in solution at a micro-dose was exposed to the epithelial side of rabbit, porcine, or bovine corneas mounted in a diffusion chamber, and the corneal drug permeability and tissue uptake were monitored using an LC-MS/MS method. Data obtained were used to construct and evaluate over 46,000 quantitative structure-permeability (QSPR) models using multiple linear regression, and the best-fit models were cross-validated by Y-randomization. Drug permeability was generally higher in rabbit cornea and comparable between bovine and porcine corneas. Permeability differences between species could be explained in part by differences in corneal thickness. Corneal uptake between species correlated with a slope close to 1, indicating generally similar drug uptake per unit weight of tissue. A high correlation was observed between bovine, porcine, and rabbit corneas for permeability and between bovine and porcine corneas for uptake (R2 ≥ 0.94). MLR models indicated that drug characteristics such as lipophilicity (LogD), heteroatom ratio (HR), nitrogen ratio (NR), hydrogen bond acceptors (HBA), rotatable bonds (RB), index of refraction (IR), and tissue thickness (TT) are of great influence on drug permeability and uptake. When data for all species along with thickness as a parameter was used in MLR, the best fit equation for permeability was Log (% transport/cm2·s) = 0.441 LogD - 8.29 IR + 8.357 NR - 0.279 HBA - 3.833 TT + 10.432 (R2 = 0.826), and the best-fit equation for uptake was Log (%/g) = 0.387 LogD + 4.442 HR + 0.105 RB - 0.303 HBA - 2.235 TT + 1.422 (R2 = 0.750). Thus, it is feasible to explain corneal drug delivery in three species using a single equation.

2.
Doc Ophthalmol ; 147(1): 71-75, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37369909

RESUMO

BACKGROUND: Pseudophakic cystoid macular edema (PCME) is the most common cause of visual acuity deterioration after uncomplicated cataract surgery. There is no consensus regarding how to manage recurrent or refractory cases. REPORT: A 54-year-old woman complained of decreased vision and central metamorphopsia in the right eye (OD) 3 months after uneventful cataract surgery. Visual acuity was 0.3 logMAR (20/40) OD and 0.1 logMAR (20/25) OS. Reduced macular brightness was seen OD on funduscopy associated with increased macular thickness on optical coherence tomography (OCT). Pseudophakic cystoid macular edema (PCME) was diagnosed, and treatment with oral acetazolamide was tried without success. The patient underwent a single intravitreal injection of an acetazolamide implant (260 µg) OD as off-label treatment. Four weeks following the injection, she reported complete resolution of her metamorphopsia and visual loss OD. Four months later, her visual acuity was 0.0 logMAR (20/20) in OD and 0.1 logMAR (20/25) in OS. The patient reported no discomfort after the injection procedure. Laboratory and ophthalmologic tests did not identify any adverse effects of the medication. CONCLUSION: We show that PCME refractory to conventional treatment improved after intravitreal acetazolamide implant injection. Further investigation is warranted to confirm these preliminary findings.


Assuntos
Extração de Catarata , Catarata , Edema Macular , Humanos , Feminino , Pessoa de Meia-Idade , Edema Macular/diagnóstico , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Acetazolamida/uso terapêutico , Eletrorretinografia , Extração de Catarata/efeitos adversos , Tomografia de Coerência Óptica , Injeções Intravítreas , Catarata/complicações , Catarata/tratamento farmacológico
3.
Rev Soc Bras Med Trop ; 56: e05522022, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37222350

RESUMO

BACKGROUND: Ocular toxoplasmosis is the leading cause of infectious posterior uveitis worldwide, accounting for 30-50% of all cases in immunocompetent patients. Conventional treatment is associated with adverse effects and does not prevent recurrence. Intravitreal drug administration can improve disease outcomes and reduce side effects. Herein, we conducted a systematic review and meta-analysis on the efficacy of intravitreal injections for treating ocular toxoplasmosis. METHODS: The systematic search was conducted using PubMed, SciELO, and Google Scholar with the descriptors "ocular toxoplasmosis" AND "intravitreal". We analyzed studies that met the inclusion criteria, i.e., experimental cases in patients treated intravitreally for ocular toxoplasmosis. Considering the systematic review, we focused on the number of intravitreal injections, the therapeutic drug class, and the presence of preexisting conditions. To assess the efficacy of intravitreal injections, a meta-analysis was performed using visual acuity, side effects, disease recurrence, and inflammatory responses as variables. RESULTS: Intravitreal injection-induced side effects were rarely observed (0.49% [0.00, 1.51%] ). The use of antiparasitic and anti-inflammatory drugs afforded improved visual acuity (99.81% [98.60, 100.00%]) and marked effectiveness in treating ocular toxoplasmosis. CONCLUSIONS: Intravitreal injections may facilitate the successful treatment of ocular toxoplasmosis. However, clinicians should carefully evaluate the presence of preexisting conditions for ocular toxoplasmosis or previous diseases, as these can impact the decision to administer intravitreal injections.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Infecções Oculares , Toxoplasmose , Humanos
4.
Int J Pharm ; 636: 122809, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36894043

RESUMO

Intravitreal injections are the preferred choice for drug administration to the posterior segment of the eye. However, the required frequent injections may cause complications to the patient and low adherence to the treatment. Intravitreal implants are able to maintain therapeutic levels for a long period. Biodegradable nanofibers can modulate drug release and allow the incorporation of fragile bioactive drugs. Age-related macular degeneration is one of the world major causes of blindness and irreversible vision loss. It involves the interaction between VEGF and inflammatory cells. In this work we developed nanofiber-coated intravitreal implants containing dexamethasone and bevacizumab for simultaneously delivery of these drugs. The implant was successfully prepared and the efficiency of the coating process was confirmed by scanning electron microscopy. Around 68% of dexamethasone was released in 35 days and 88% of bevacizumab in 48hs. The formulation presented activity in the reduction of vessels and was safe to the retina. It was not observed any clinical or histopathological change, neither alteration in retina function or thickness by electroretinogram and optical coherence tomography during 28 days. The nanofiber-coated implants of dexamethasone and bevacizumab may be considered as a new delivery system that can be effective for the treatment of AMD.


Assuntos
Glucocorticoides , Nanofibras , Animais , Coelhos , Bevacizumab , Dexametasona , Implantes de Medicamento , Injeções Intravítreas , Inibidores da Angiogênese , Resultado do Tratamento
5.
Pharmaceutics ; 15(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36678822

RESUMO

Mometasone furoate (MF) is a medium-potency synthetic glucocorticosteroid with anti-inflammatory, antipruritic, and vasoconstrictive properties. However, its role in the treatment of ocular inflammation has not yet been explored. This work investigated the anti-inflammatory activity of MF in ocular tissues. First, the in vivo safety of the intravitreal (IVT) injection of MF (80, 160, and 240 µg) was evaluated via clinical examination (including the assessment of intraocular pressure), electroretinography (ERG), and histopathology. Second, MF was tested in an experimental model of bacillus Calmette-Guérin (BCG)-induced uveitis in Wistar rats. Intraocular inflammation was then evaluated via a slit-lamp and fundus examination, ERG, histopathology, and the quantification of pro-inflammatory markers. Intravitreal MF showed no toxicity in all the investigated doses, with 160 µg leading to attenuated disease progression and improvement in clinical, morphological, and functional parameters. There was a significant reduction in the levels of inflammatory markers (myeloperoxidase, interleukins 6 and 1ß, CXCL-1, and tumor necrosis factor-alpha) when compared to the levels in untreated animals. Therefore, MF should be further investigated as a promising drug for the treatment of ocular inflammation.

6.
Int J Pharm ; 631: 122468, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36503038

RESUMO

Ocular chemical burns are prevalent injuries that must have immediate and effective treatment to avoid complications. Aiming to improve bioavailability and efficacy, a poloxamer-based thermoresponsive in-situ gelling system containing hyaluronic acid and indomethacin was developed. Formulations with different polymeric proportions were screened through rheological measurements resulting in an optimized system (F2) with gelling temperature of 34.2 ± 0.11 °C. Its maximum viscosity varied from 77.33 mPa (25 °C) to 82.95 mPa (34 °C) following a non-Newtonian profile and a pH of 6.86 ± 0.01. No incompatibilities were found after infrared analysis. Polarized light microscopy and cryo-transmission electron microscopy have demonstrated micelles of nano-sized dimensions (21.86 nm) with indomethacin entrapped in the core, forming a polymeric network under heating. In vitro tests revealed a cumulative release of 59.75 ± 3.17 % up to 24 h under a sustained release profile. Results from HET-CAM assay indicated that F2 was well tolerated. Corneal wound healing was significantly faster in animals treated with F2 compared to a commercial formulation and an untreated group. These findings suggests that F2 could be an efficient system to delivery drugs into the ocular surface improving wound healing.


Assuntos
Queimaduras Químicas , Indometacina , Animais , Ácido Hialurônico , Queimaduras Químicas/tratamento farmacológico , Géis , Poloxâmero
7.
Rev. Soc. Bras. Med. Trop ; 56: e0552, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1441077

RESUMO

ABSTRACT Background: Ocular toxoplasmosis is the leading cause of infectious posterior uveitis worldwide, accounting for 30-50% of all cases in immunocompetent patients. Conventional treatment is associated with adverse effects and does not prevent recurrence. Intravitreal drug administration can improve disease outcomes and reduce side effects. Herein, we conducted a systematic review and meta-analysis on the efficacy of intravitreal injections for treating ocular toxoplasmosis. Methods: The systematic search was conducted using PubMed, SciELO, and Google Scholar with the descriptors "ocular toxoplasmosis" AND "intravitreal". We analyzed studies that met the inclusion criteria, i.e., experimental cases in patients treated intravitreally for ocular toxoplasmosis. Considering the systematic review, we focused on the number of intravitreal injections, the therapeutic drug class, and the presence of preexisting conditions. To assess the efficacy of intravitreal injections, a meta-analysis was performed using visual acuity, side effects, disease recurrence, and inflammatory responses as variables. Results: Intravitreal injection-induced side effects were rarely observed (0.49% [0.00, 1.51%] ). The use of antiparasitic and anti-inflammatory drugs afforded improved visual acuity (99.81% [98.60, 100.00%]) and marked effectiveness in treating ocular toxoplasmosis. Conclusions: Intravitreal injections may facilitate the successful treatment of ocular toxoplasmosis. However, clinicians should carefully evaluate the presence of preexisting conditions for ocular toxoplasmosis or previous diseases, as these can impact the decision to administer intravitreal injections.

8.
Pharmaceutics ; 14(11)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36365212

RESUMO

Doxorubicin (DOX) is an antineoplastic agent clinically employed for treating breast cancer patients. Despite its effectiveness, its inherent adverse toxic side effects often limit its clinical application. To overcome these drawbacks, lipid-polymer hybrid nanoparticles (LPNP) arise as promising nanoplatforms that combine the advantages of both liposomes and polymeric nanoparticles into a single delivery system. Alpha-tocopherol succinate (TS) is a derivative of vitamin E that shows potent anticancer mechanisms, and it is an interesting approach as adjuvant. In this study, we designed a pH-sensitive PLGA-polymer-core/TPGS-lipid-shell hybrid nanoparticle, loaded with DOX and TS (LPNP_TS-DOX). Nanoparticles were physicochemically and morphologically characterized. Cytotoxicity studies, migration assay, and cellular uptake were performed in 4T1, MCF-7, and MDA-MB-231 cell lines. Antitumor activity in vivo was evaluated in 4T1 breast tumor-bearing mice. In vitro studies showed a significant reduction in cell viability, cell migration, and an increase in cellular uptake for the 4T1 cell line compared to free DOX. In vivo antitumor activity showed that LPNP-TS-DOX was more effective in controlling tumor growth than other treatments. The high cellular internalization and the pH-triggered payload release of DOX lead to the increased accumulation of the drugs in the tumor area, along with the synergic combination with TS, culminating in greater antitumor efficacy. These data support LPNP-TS-DOX as a promising drug delivery system for breast cancer treatment.

9.
Eur J Pharm Biopharm ; 179: 26-36, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36041595

RESUMO

Sodium butyrate-loaded nanoparticles coated chitosan (NaBu-loaded nanoparticles/CS) were developed to treat the choroidal neovascularization in wet age-related macular degeneration (AMD). The nanoparticles were produced by double emulsification and solvent evaporation technique, optimized by experimental statistical design, characterized by analytical methods, investigated in terms of in vitro and in vivo ocular biocompatibility, and evaluated as an antiangiogenic system in vivo. The NaBu-loaded nanoparticles/CS were 311.1 ± 3.1 nm in diameter with a 0.208 ± 0.007 polydispersity index; had a +56.3 ± 2.6 mV zeta potential; showed a 92.3 % NaBu encapsulation efficiency; and sustained the drug release over 35 days. The NaBu-loaded nanoparticles/CS showed no toxicity to human retinal pigment epithelium cells (ARPE-19 cells); was not irritant to the chorioallantoic membrane (CAM); did not interfere in the integrity of the retinal layers of rat's eyes, as detected by the Optical Coherence Tomography and histopathology; and inhibited the angiogenesis in CAM assay. The NaBu-loaded nanoparticles/CS could be a therapeutic alternative to limit the neovascularization in AMD.


Assuntos
Quitosana , Nanopartículas , Degeneração Macular Exsudativa , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Ácido Butírico/uso terapêutico , Humanos , Ratos , Solventes , Degeneração Macular Exsudativa/tratamento farmacológico
10.
J Control Release ; 350: 228-243, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35995297

RESUMO

Vectorized small interfering RNAs (siRNAs) are widely used to induce gene silencing. Among the delivery systems used, lipid-based particles are the most effective. Our objective was the development of novel lipid-polymer hybrid nanoparticles, from lipoplexes (complexes of cationic lipid and siRNAs), and poly (lactic-co-glycolic acid) (PLGA), using a simple modified nanoprecipitation method. Due to their morphology, we called these hybrid nanoparticles Spheroplexes. We elucidated their structure using several physico-chemical techniques and showed that they are composed of a hydrophobic PLGA matrix, surrounded by a lipid envelope adopting a lamellar structure, in which the siRNA is complexed, and they retain surface characteristics identical to the starting nanoparticles, i.e. lipoplexes siRNA. We analyzed the composition of the particle population and determined the final percentage of spheroplexes within this population, 80 to 85% depending on the preparation conditions, using fluorescent markers and the ability of flow cytometry to detect nanometric particles (approximately 200 nm). Finally, we showed that spheroplexes are very stable particles and more efficient than siRNA lipoplexes for the delivery of siRNA to cultured cells. We administered spheroplexes contain siRNAs targeting TNF-α to mice with ulcerative colitis induced by dextran sulfate and our results indicate a disease regression effect with a response probably mediated by their uptake by macrophages / monocytes at the level of lamina propria of the colon. The efficacy of decreased level of TNF-α in vivo seemed to be an association of spheroplexes polymer-lipid composition and the specific siRNA. These results demonstrate that spheroplexes are a promising hybrid nanoparticle for the oral delivery of siRNA to the colon.


Assuntos
Nanopartículas , Fator de Necrose Tumoral alfa , Animais , Cátions/química , Sulfato de Dextrana , Lipídeos/química , Lipossomos , Camundongos , Nanopartículas/química , Polímeros/química , RNA Interferente Pequeno
11.
Pharmaceutics ; 14(7)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35890326

RESUMO

The eye is an organ with limited drug access due to its anatomical and physiological barriers, and the usual forms of ocular administration are limited in terms of drug penetration, residence time, and bioavailability, as well as low patient compliance. Hence, therapeutic innovations in new drug delivery systems (DDS) have been widely explored since they show numerous advantages over conventional methods, besides delivering the content to the eye without interfering with its normal functioning. Polymers are usually used in DDS and many of them are applicable to ophthalmic use, especially biodegradable ones. Even so, it can be a hard task to find a singular polymer with all the desirable properties to deliver the best performance, and combining two or more polymers in a blend has proven to be more convenient, efficient, and cost-effective. This review was carried out to assess the use of polymer blends as DDS. The search conducted in the databases of Pubmed and Scopus for specific terms revealed that although the physical combination of polymers is largely applied, the term polymer blend still has low compliance.

12.
Artigo em Inglês | MEDLINE | ID: mdl-35647524

RESUMO

Uveitis is a group of sight-threatening ocular inflammatory disorders, whose mainstay of therapy is associated with severe adverse events, prompting the investigation of alternative treatments. The peptide melittin (MEL) is the major component of Apis mellifera bee venom and presents anti-inflammatory and antiangiogenic activities, with possible application in ophthalmology. This work aims to investigate the potential of intravitreal MEL in the treatment of ocular diseases involving inflammatory processes, especially uveitis. Safety of MEL was assessed in retinal cells, chick embryo chorioallantoic membranes, and rats. MEL at concentrations safe for intravitreal administration showed an antiangiogenic activity in the chorioallantoic membrane model comparable to bevacizumab, used as positive control. A protective anti-inflammatory effect in retinal cells stimulated with lipopolysaccharide (LPS) was also observed, without toxic effects. Finally, rats with bacille Calmette-Guerin- (BCG) induced uveitis treated with intravitreal MEL showed attenuated disease progression and improvement of clinical, morphological, and functional parameters, in addition to decreased levels of proinflammatory mediators in the posterior segment of the eye. These effects were comparable to the response observed with corticosteroid treatment. Therefore, MEL presents adequate safety profile for intraocular administration and has therapeutic potential as an anti-inflammatory and antiangiogenic agent for ocular diseases.

13.
Rev. ciênc. farm. básica apl ; 43: 1-10, 20220101.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1349119

RESUMO

At present, ophthalmic drug delivery remains a major challenge, given the eye's protective structure and susceptibility to irritation, resulting in poor patient adherence. In order to overcome these constraints, new formulations are continually being developed. The inclusion of Galactoxyloglucan (Tamarind seed polysaccharide (TSP) in such formulations, a natural substance extracted from the seeds of Tamarindus indica, has shown great potential due to its physicochemical properties, high biocompatibility and safety profile. Such properties, have led to its use in formulations for the treatment of dry eye disease, glaucoma, and bacterial keratitis, as well as in dilating eye drops used in eye examinations. In this article, we highlight the most recent TSPbased ophthalmologic formulations, which indicate that this polymer is a strong candidate to reduce adverse effects, improve patient tolerability and drug bioavailability.

14.
Braz. J. Pharm. Sci. (Online) ; 58: e21310, 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1420508

RESUMO

Abstract In the hospital environment, postoperative pain is a common occurrence that impairs patient recovery and rehabilitation and lengthens hospitalization time. Racemic bupivacaine hydrochloride (CBV) and Novabupi® (NBV) (S (-) 75% R (+) 25% bupivacaine hydrochloride) are two examples of local anesthetics used in pain management, the latter being an alternative with less deleterious effects. In the present study, biodegradable implants were developed using Poly(L-lactide-co-glycolide) through a hot molding technique, evaluating their physicochemical properties and their in vitro drug release. Different proportions of drugs and polymer were tested, and the proportion of 25%:75% was the most stable for molding the implants. Thermal and spectrometric analyses were performed, and they revealed no unwanted chemical interactions between drugs and polymer. They also confirmed that heating and freeze-drying used for manufacturing did not interfere with stability. The in vitro release results revealed drugs sustained release, reaching 64% for NBV-PLGA and 52% for CBV-PLGA up to 30 days. The drug release mechanism was confirmed by microscopy, which involved pores formation and polymeric erosion, visualized in the first 72 h of the in vitro release test. These findings suggest that the developed implants are interesting alternatives to control postoperative pain efficiently.


Assuntos
Dor Pós-Operatória/classificação , Bupivacaína/análise , Implantes Absorvíveis/classificação , Anestésicos Locais/administração & dosagem , Técnicas In Vitro/métodos , Preparações Farmacêuticas/análise , Hospitais/classificação
15.
Pharmaceutics ; 13(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34575459

RESUMO

There have been major advances in the treatment of eye diseases over the last years [...].

16.
Biomed Pharmacother ; 143: 112145, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34507119

RESUMO

Lupeol is a pentacyclic triterpene with known anti-inflammatory effects. However, its role in the treatment of noninfectious uveitis has not been explored. This work investigated anti-inflammatory activity of lupeol in ocular tissues with in vitro and in vivo models. First, we evaluated the effect of lupeol (100 µM) on inflammatory response induced by lipopolysaccharide (LPS) in retinal pigment epithelium cells (ARPE-19) by measuring levels of released interleukins (IL-6 and IL-8). Then, we investigated the anti-inflammatory action of intravitreal lupeol in a rodent model of panuveitis induced by Mycobacterium bovis Calmette-Guérin Bacillus (BCG). Rats were submitted to electroretinography and clinical analyses on days 3, 7, and 15 after uveitis induction. In addition, histopathological analysis, and indirect quantification of myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) in the posterior segment were performed. Treatment with lupeol (100 µM) significantly decreased IL-6 and IL-8 levels in comparison to untreated LPS-activated ARPE-19 cells. This reduction was similar to that detected in ARPE-19 cells treated with dexamethasone. The results of the in vivo assay demonstrated that intravitreal lupeol is able to modulate inflammation in the anterior and posterior segment of the rat eyes, indicating that it should be further investigated as a novel potential candidate for management of uveitis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Olho/efeitos dos fármacos , Triterpenos Pentacíclicos/administração & dosagem , Uveíte/tratamento farmacológico , Acetilglucosaminidase/metabolismo , Animais , Vacina BCG , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação para Baixo , Olho/metabolismo , Olho/patologia , Humanos , Mediadores da Inflamação/metabolismo , Injeções Intravítreas , Lipopolissacarídeos/toxicidade , Masculino , Peroxidase/metabolismo , Ratos Wistar , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Uveíte/induzido quimicamente , Uveíte/metabolismo , Uveíte/patologia
17.
Pharmaceutics ; 13(6)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34200993

RESUMO

Since the possibility of silencing specific genes linked to retinal degeneration has become a reality with the use of small interfering RNAs (siRNAs), this technology has been widely studied to promote the treatment of several ocular diseases. Despite recent advances, the clinical success of gene silencing in the retina is significantly reduced by inherent anatomical and physiological ocular barriers, and new strategies are required to achieve intraocular therapeutic effectiveness. In this study, we developed lipoplexes, prepared with sodium alginate as an adjuvant and strategically coated with hyaluronic acid (HA-LIP), and investigated the potential neuroprotective effect of these systems in a retinal light damage model. Successful functionalization of the lipoplexes with hyaluronic acid was indicated in the dynamic light scattering and transmission electron microscopy results. Moreover, these HA-LIP nanoparticles were able to protect and deliver siRNA molecules targeting caspase-3 into the retina. After retinal degeneration induced by high light exposure, in vitro and in vivo quantitative reverse transcription-PCR (RT-qPCR) assays demonstrated significant inhibition of caspase-3 expression by HA-LIP. Furthermore, these systems were shown to be safe, as no evidence of retinal toxicity was observed by electroretinography, clinical evaluation or histology.

18.
Doc Ophthalmol ; 143(3): 259-270, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34036478

RESUMO

PURPOSE: Assessment of the anti-angiogenic activity and the safety of ophthalmic use of four pentacyclic triterpenes (friedelin, friedelinol, lupenone, and lupeol). METHODS: Triterpenes cytotoxicity (5-640 µmol L-1) was examined in ARPE-19 cells by sulforhodamine B colorimetric method, and the anti-angiogenic activity (50-1000 µmol L-1) was evaluated in the chorioallantoic membrane model. Full-field electroretinography and histological analysis were performed to evaluate intraocular effects of these four triterpenes (at 100 or 500 µmol L-1) in eyes of Wistar rats, for 15 days. RESULTS: In the cytotoxicity assay, friedelin and friedelinol were not able to drastically reduce cell growth. A dose-dependent response was observed in groups exposed to lupeol or lupenone. During the chorioallantoic membrane assay, friedelinol at 500 µmol L-1 reduced the vascularity in 26%; lupeol and lupenone showed promising anti-angiogenic activity, reducing three parameters: vascularized area (> 30%), number of junctions (> 20%), and vessel length (> 15%). According to the electroretinographic and histologic findings, triterpenes at 100 µmol L-1 or lupenone at 500 µmol L-1 did not induce any transient or permanent disturbance in retinal structure or functioning. CONCLUSIONS: Triterpenes at 100 µmol L-1 or lupenone at 500 µmol L-1 were considered safe for potential ophthalmic use.


Assuntos
Eletrorretinografia , Triterpenos , Animais , Membrana Corioalantoide , Ratos , Ratos Wistar , Retina , Triterpenos/toxicidade
19.
Am J Ophthalmol Case Rep ; 22: 101093, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33981913

RESUMO

PURPOSE: To report the first patient with ocular toxoplasmosis treated with a slow-release biodegradable intravitreal clindamycin implant. OBSERVATIONS: A 39-year-old human immunodeficiency virus (HIV)-positive woman with recurrent toxoplasmic retinochoroiditis and vitritis for whom oral medication was medically contraindicated was treated with an intravitreal slow-release clindamycin implant and three monthly intravitreal injections of clindamycin and dexamethasone. Serial ophthalmologic examinations demonstrated gradual, complete resolution of posterior uveitis and healing of the retinochoroidal lesion with cicatricial changes, as well as gradual improvement of cells in the anterior chamber. There was no significant change in electroretinography waves after treatment with the implant. The presence of the implant, or part of it, was detectable in the vitreous cavity for 4 months. To date, the patient has been monitored for 30 months, and there has been no reactivation of ocular toxoplasmosis. CONCLUSION: The slow-release clindamycin implant was safe for intravitreal use in this patient and may have contributed to the long-term control of toxoplasmosis chorioretinitis.

20.
Eur J Pharm Sci ; 163: 105852, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862240

RESUMO

Biodegradable polymeric nanofibers containing mometasone furoate can be a new approach to drug delivery to treat chronic rhinosinusitis, providing controlled steroid delivery to the sinonasal mucosa. This study aimed to develop biodegradable polymeric nanofibers and explore the safety of these fibers in an in vivo rabbit model. The nanofibers' development has been optimized using the Response Surface Methodology (RSM) obtained with Design of Experiments (DoE) with the best conditions related to the polymer concentration and proportion of solvents used in the electrospinning process. The nanofibers were prepared, operating as a determinant factor, the nanofiber formation and its diameter evaluated by Scanning Electron Microscopy (SEM). The ideal system obtained was assessed by SEM, thermogravimetric analysis (TGA), X-ray diffraction (XRD), differential scanning calorimetry (DSC), assay, and drug delivery by UHLPC validated method. The results showed that the drug is dispersed in the polymeric matrix, is stable, and showed sustained release kinetics in a bio-relevant nasal environment (Higuchi model kinetics). In vivo tests, the level of inflammation at the animals' mucosa which received the nanofiber with the mometasone furoate was lower than those that received the nanofibers without the drug (α = 0.05). Histopathology analysis showed that the polymeric nanofibers containing mometasone are safe when topically applied on the sinonasal mucosa, opening a new horizon in chronic rhinosinusitis treatment.


Assuntos
Nanofibras , Animais , Varredura Diferencial de Calorimetria , Microscopia Eletrônica de Varredura , Polímeros , Coelhos , Difração de Raios X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...