1
|
Hammid A, Honkakoski P. Ocular Drug-Metabolizing Enzymes: Focus on Esterases. Drug Metab Rev 2024:1-23. [PMID: 38888291 DOI: 10.1080/03602532.2024.2368247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 06/10/2024] [Indexed: 06/20/2024]
Affiliation(s)
- Anam Hammid
- School of Pharmacy, University of Eastern Finland, Yliopistonrinne3, FI-70210 Kuopio, Finland
| | - Paavo Honkakoski
- School of Pharmacy, University of Eastern Finland, Yliopistonrinne3, FI-70210 Kuopio, Finland
| |
Collapse
|
2
|
Zhang Z, Ma Q, Dai Z, Hong J, Gu J, Shi R, Xu J, Ma Y, Sun X, Sun J. Sustained release of brimonidine from conjunctival sac insert to reduce intraocular pressure for glaucoma treatment. Expert Opin Drug Deliv 2024; 21:975-986. [PMID: 38975698 DOI: 10.1080/17425247.2024.2378082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 06/11/2024] [Indexed: 07/09/2024]
Abstract
BACKGROUND Glaucoma is one of the major irreversible blinding eye diseases in the world. Reducing intraocular pressure (IOP) is the primary treatment option, and taking eye drops daily is the common method. However, short drug duration and poor bioavailability of eye drops may lead to unsatisfied therapeutic effects and inadequate patient compliance. METHODS A brimonidine-loaded silicone rubber insert (BRI@SR@PT) was prepared by loading brimonidine into a surface-modified silicone rubber ring, followed by polydopamine/thermoplastic polyurethane coatings. The physical properties, in vitro cytocompatibility and drug release of BRI@SR@PT were investigated. The BRI@SR@PT was administrated in the conjunctival sac of rabbit eyes, and its in vivo drug release, IOP-lowering efficacy and biosafety were assessed. RESULTS The BRI@SR@PT presented great thermal stability and excellent elasticity. The BRI@SR@PT was able to release BRI sustainably for 28 days with little toxicity in vitro. Compared to BRI eye drops, the BRI@SR@PT effectively lowered IOP for 21 days based on the sustained BRI release with great biosafety when administrated in conjunctival sac of rabbit eyes in a noninvasive fashion. CONCLUSIONS The conjunctival sac insert (BRI@SR@PT), as a promising drug-delivery platform, may provide a sustained IOP-lowering treatment for patients with ocular hypertension or glaucoma, without the need for invasive procedures.
Collapse
Affiliation(s)
- Zhutian Zhang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Qian Ma
- Department of Ophthalmology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Zhaoxing Dai
- Shanghai Haohai Biological Technology Co. Ltd, Shanghai, China
| | - Jiaxu Hong
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Jifeng Gu
- Department of Pharmacy, Eye & ENT Hospital, Shanghai Key Laboratory of Bioactive Small Molecules, Fudan University, Shanghai, China
| | - Rong Shi
- Science and Technology Experimental Center, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Jianjiang Xu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Yaling Ma
- Department of Ophthalmology, General Hospital of Ningxia Medical University, Yinchuan, Ningxia, China
| | - Xinghuai Sun
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Jianguo Sun
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
- State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| |
Collapse
|
3
|
Hammid A, Fallon JK, Vellonen KS, Lassila T, Reinisalo M, Urtti A, Gonzalez F, Tolonen A, Smith PC, Honkakoski P. Aldehyde oxidase 1 activity and protein expression in human, rabbit, and pig ocular tissues. Eur J Pharm Sci 2023; 191:106603. [PMID: 37827455 DOI: 10.1016/j.ejps.2023.106603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 09/18/2023] [Accepted: 10/06/2023] [Indexed: 10/14/2023]
Abstract
Aldehyde oxidase (AOX) is a cytosolic drug-metabolizing enzyme which has attracted increasing attention in drug development due to its high hepatic expression, broad substrate profile and species differences. In contrast, there is limited information on the presence and activity of AOX in extrahepatic tissues including ocular tissues. Because several ocular drugs are potential substrates for AOX, we performed a comprehensive analysis of the AOX1 expression and activity profile in seven ocular tissues from humans, rabbits, and pigs. AOX activities were determined using optimized assays for the established human AOX1 probe substrates 4-dimethylamino-cinnamaldehyde (DMAC) and phthalazine. Inhibition studies were undertaken in conjunctival and retinal homogenates using well-established human AOX1 inhibitors menadione and chlorpromazine. AOX1 protein contents were quantitated with targeted proteomics and confirmed by immunoblotting. Overall, DMAC oxidation rates varied over 10-fold between species (human ˃˃ rabbit ˃ pig) and showed 2- to 6-fold differences between tissues from the same species. Menadione seemed a more potent inhibitor of DMAC oxidation across species than chlorpromazine. Human AOX1 protein levels were highest in the conjunctiva, followed by most posterior tissues, whereas anterior tissues showed low levels. The rabbit AOX1 expression was high in the conjunctiva, retinal pigment epithelial (RPE), and choroid while lower in the anterior tissues. Quantification of pig AOX1 was not successful but immunoblotting confirmed the presence of AOX1 in all species. DMAC oxidation rates and AOX1 contents correlated quite well in humans and rabbits. This study provides, for the first time, insights into the ocular expression and activity of AOX1 among multiple species.
Collapse
Affiliation(s)
- Anam Hammid
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1 C, FI-70210 Kuopio, Finland.
| | - John K Fallon
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Campus Box 7355, Chapel Hill, NC 27599-7355, United States
| | - Kati-Sisko Vellonen
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1 C, FI-70210 Kuopio, Finland
| | - Toni Lassila
- Admescope Ltd, Typpitie 1, FI-90620 Oulu, Finland
| | - Mika Reinisalo
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1 C, FI-70210 Kuopio, Finland
| | - Arto Urtti
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1 C, FI-70210 Kuopio, Finland; Faculty of Pharmacy, University of Helsinki, Viikinkaari 5 E, FI-00790 Helsinki, Finland
| | - Francisco Gonzalez
- Center for Research in Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela, 15782 Santiago de Compostela, Spain; Service of Ophthalmology, University Hospital of Santiago de Compostela, and Fundacion Instituto de Investigacion Sanitaria de Santiago de Compostela (FIDIS), 15706 Santiago de Compostela, Spain
| | - Ari Tolonen
- Admescope Ltd, Typpitie 1, FI-90620 Oulu, Finland
| | - Philip C Smith
- Division of Pharmacoengineering and Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Campus Box 7355, Chapel Hill, NC 27599-7355, United States
| | - Paavo Honkakoski
- School of Pharmacy, University of Eastern Finland, Yliopistonranta 1 C, FI-70210 Kuopio, Finland
| |
Collapse
|
4
|
Kunikane E, Orii Y, Inoue A, Inatani M. Patient Factors Influencing Intraocular Penetration of Brimonidine-Related Eye Drops in Adults: A Post Hoc Pooled Analysis. Ophthalmol Ther 2023; 12:3083-3098. [PMID: 37676633 PMCID: PMC10640521 DOI: 10.1007/s40123-023-00794-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 08/11/2023] [Indexed: 09/08/2023] Open
Abstract
INTRODUCTION The factors related to the ocular penetration of drugs after the administration of eye drops in humans have not been examined in detail. Therefore, this study assessed the influence of patient factors on the intraocular penetration of eye drops. METHODS A pooled analysis was performed on the data of 42 participants from three studies to evaluate the ocular pharmacokinetics in humans after the topical application of brimonidine-related eye drops. The patients were scheduled for vitrectomy and received brimonidine-related eye drops (0.1% brimonidine tartrate ophthalmic solution, 0.1% brimonidine tartrate and 0.5% timolol fixed-combination ophthalmic solution, or 0.1% brimonidine tartrate and 1% brinzolamide fixed-combination suspension) twice daily for 1 week. We analyzed the effects of patient factors (sex, the presence or absence of lens, age, corneal thickness, corneal endothelial cell density, tear secretion, eye axial length, height, weight and body mass index [BMI]) on brimonidine, timolol and brinzolamide concentrations in the aqueous and vitreous humor after topical application. RESULTS The drug concentrations in the aqueous and vitreous humor were not significantly different, regardless of sex or the presence or absence of lens. Age correlated positively with brimonidine (r = 0.3948, p = 0.012) and brinzolamide (r = 0.6809, p = 0.030) concentrations in the aqueous humor; the correlation with timolol showed a trend towards significance (r = 0.6425, p = 0.086). Corneal thickness, corneal endothelial cell density, tear secretion, eye axial length, height and BMI did not correlate with the drug concentrations in the aqueous or vitreous humor. Timolol concentration in the vitreous humor was negatively correlated with weight (r = - 0.8333, p = 0.010). CONCLUSION The findings of this study emphasize the necessity of considering individual differences in ocular pharmacokinetics during drug therapy (formulation design of the eye drops and dose regimen).
Collapse
Affiliation(s)
| | - Yusuke Orii
- Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Akiko Inoue
- Senju Pharmaceutical Co., Ltd., Osaka, Japan
| | - Masaru Inatani
- Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| |
Collapse
|
5
|
Xiang A, He H, Yu H, Li A, Luo Y, Yang J, Zhong X. Ocular Posterior Segment Distribution and Pharmacokinetics of Brimonidine After Intravitreal Administration in Guinea Pigs. J Ocul Pharmacol Ther 2023; 39:456-462. [PMID: 37311153 DOI: 10.1089/jop.2023.0020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
Purpose: Brimonidine is a highly alpha-2 adrenergic agonist, which provides a potential myopia control effect. This study aimed to examine the pharmacokinetics and concentration of brimonidine in the posterior segment tissue of eyes in guinea pigs. Methods: A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was successfully used for brimonidine pharmacokinetics and tissue distribution research in guinea pigs following intravitreal administration (20 μg/eye). Results: Brimonidine concentrations in the retina and sclera were maintained at a high level (>60 ng/g) at 96 h postdosing. Brimonidine concentration peaked in the retina (377.86 ng/g) at 2.41 h and sclera (306.18 ng/g) at 6.98 h. The area under curve (AUC0-∞) was 27,179.99 ng h/g in the retina and 39,529.03 ng h/g in the sclera. The elimination half-life (T1/2e) was 62.43 h in the retina and 67.94 h in the sclera. Conclusions: The results indicated that brimonidine was rapidly absorbed and diffused to the retina and sclera. Meanwhile, it maintained higher posterior tissue concentrations, which can effectively activate the alpha-2 adrenergic receptor. This may provide pharmacokinetic evidence for the inhibition of myopia progression by brimonidine in animal experiments.
Collapse
Affiliation(s)
- Aiqun Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Hong He
- Hainan Eye Hospital and Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Haikou, China
| | - Hanyang Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Anzhen Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yanting Luo
- Hainan Eye Hospital and Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Haikou, China
| | - Junming Yang
- Hainan Eye Hospital and Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Haikou, China
| | - Xingwu Zhong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
- Hainan Eye Hospital and Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Haikou, China
| |
Collapse
|
6
|
Khopade AJ, Halder A, Patel V, Upadhyay S, Burade V, Pateliya B, Panchal S, Mandhane S, Awati C, Zope M. Preclinical Evaluation of a Novel Once-a-Day Brimonidine Ophthalmic Nanosuspension. J Ocul Pharmacol Ther 2023. [PMID: 37646731 DOI: 10.1089/jop.2023.0038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023] Open
Abstract
Purpose: This article aims to describe a preclinical proof of concept for a novel once-a-day (OD) brimonidine ophthalmic nanosuspension. Methods: The preclinical proof of concept was established using New Zealand white rabbits as animal models. Dose-finding, multiple-dose efficacy, ocular pharmacokinetic, and hemodynamic studies were performed in normotensive rabbits. Steroid-induced ocular hypertension model in rabbits was used to study efficacy in glaucomatous pathophysiology. The test (0.35% OD suspension) and reference (0.15% three times a day [TID] solution) were compared. Results: The intraocular pressure (IOP) reduction was sustained for 0.35% and 0.5% strengths but not for other lower strengths tested or reference strengths. A 0.35% OD suspension reduced IOP >2 mmHg after 24 h of dosing, which was not seen with the reference. After multiple dosing, 0.35% OD suspension reduced IOP by 4-6 mmHg after 24 h, which was comparable to the 0.15% TID reference solution. An ocular pharmacokinetic study showed that the brimonidine was rapidly absorbed and distributed throughout the eye after topical administration. Concentration was higher in tissues with high α2 receptors, such as cornea-conjunctiva, iris/ciliary body, and choroid/retina. The steady-state concentrations in these organs were also significant after 24 h of the last dose. There was an indication of increased plasma levels, so a hemodynamic study was performed to assess any adverse effects. All hemodynamic parameters were normal and no new unusual safety findings were observed. Conclusions: The study demonstrated that the novel brimonidine 0.35% ophthalmic nanosuspension is both safe and effective when administered OD and is comparable to the marketed reference formulation administered TID.
Collapse
Affiliation(s)
- Ajay J Khopade
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Arindam Halder
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Vivek Patel
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Shivam Upadhyay
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Vinod Burade
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Bharat Pateliya
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Satish Panchal
- Department of Translational Development, Sun Pharma Advanced Research Company Ltd., Vadodara, India
| | - Sanjay Mandhane
- Department of Translational Development, Sun Pharma Advanced Research Company Ltd., Vadodara, India
| | - Chandan Awati
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| | - Murlidhar Zope
- Department of Formulation R&D Non-Orals, Sun Pharmaceutical Industries Ltd., Vadodara, India
| |
Collapse
|
7
|
Kovács-Valasek A, Rák T, Pöstyéni E, Csutak A, Gábriel R. Three Major Causes of Metabolic Retinal Degenerations and Three Ways to Avoid Them. Int J Mol Sci 2023; 24:ijms24108728. [PMID: 37240082 DOI: 10.3390/ijms24108728] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/10/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
An imbalance of homeostasis in the retina leads to neuron loss and this eventually results in a deterioration of vision. If the stress threshold is exceeded, different protective/survival mechanisms are activated. Numerous key molecular actors contribute to prevalent metabolically induced retinal diseases-the three major challenges are age-related alterations, diabetic retinopathy and glaucoma. These diseases have complex dysregulation of glucose-, lipid-, amino acid or purine metabolism. In this review, we summarize current knowledge on possible ways of preventing or circumventing retinal degeneration by available methods. We intend to provide a unified background, common prevention and treatment rationale for these disorders and identify the mechanisms through which these actions protect the retina. We suggest a role for herbal medicines, internal neuroprotective substances and synthetic drugs targeting four processes: parainflammation and/or glial cell activation, ischemia and related reactive oxygen species and vascular endothelial growth factor accumulation, apoptosis and/or autophagy of nerve cells and an elevation of ocular perfusion pressure and/or intraocular pressure. We conclude that in order to achieve substantial preventive or therapeutic effects, at least two of the mentioned pathways should be targeted synergistically. A repositioning of some drugs is considered to use them for the cure of the other related conditions.
Collapse
Affiliation(s)
- Andrea Kovács-Valasek
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
| | - Tibor Rák
- Department of Ophthalmology, Medical School, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - Etelka Pöstyéni
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
| | - Adrienne Csutak
- Department of Ophthalmology, Medical School, University of Pécs, Szigeti út 12, 7624 Pécs, Hungary
| | - Robert Gábriel
- Department of Experimental Zoology and Neurobiology, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
- János Szentágothai Research Centre, University of Pécs, Ifjúság útja 20, 7624 Pécs, Hungary
| |
Collapse
|
8
|
Samoilă L, Voștinaru O, Dinte E, Bodoki AE, Iacob BC, Bodoki E, Samoilă O. Topical Treatment for Retinal Degenerative Pathologies: A Systematic Review. Int J Mol Sci 2023; 24:ijms24098045. [PMID: 37175752 PMCID: PMC10178888 DOI: 10.3390/ijms24098045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/12/2023] [Accepted: 04/25/2023] [Indexed: 05/15/2023] Open
Abstract
The topical administration of medicines is the preferred route in ocular therapy, at least for the anterior segment of the eye. However, the eye's inherent functional and biological barriers all work against the active pharmaceutical ingredient (API) to efficiently reach the targeted retinal structures. The main objective of this article is to offer a systematic review of the scientific literature in recent years, focusing on the latest developments of topical treatment intended for retinal degenerative diseases. Database search returned 102 clinical studies, focused on topical treatment for age macular degeneration, macular edemas (in diabetic retinopathy, surgery related or in retinal dystrophies) or glaucoma. After the exclusion of low-powered studies and those combining vitreo-retinal surgery, 35 articles remained for analysis. Currently, the topical treatment of retinal degenerative diseases is limited by the difficulty to deliver effective drug concentrations to the posterior eye structures. However, in the case of drug classes like NSAIDs, the presence of certain molecular and metabolic features for specific representatives makes the topical administration currently feasible in several clinical contexts. For other drug classes, either a fine-tuning of the API's pharmacokinetic profile or the use of more advanced formulation strategies, such as rationally designed nanostructured drugs and vehicles, crystalline polymorphs or supramolecular complexes, could bring the much awaited breakthrough for a more predictable and controlled delivery towards the retinal structures and could eventually be employed in the future for the development of more effective ways of delivering drugs to the posterior eye, with the ultimate goal of improving their clinical efficacy.
Collapse
Affiliation(s)
- Lăcrămioara Samoilă
- Department of Physiology, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400006 Cluj-Napoca, Romania
| | - Oliviu Voștinaru
- Department of Pharmacology, Physiology and Physiopathology, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400349 Cluj-Napoca, Romania
| | - Elena Dinte
- Department of Pharmaceutical Technology and Biopharmaceutics, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400012 Cluj-Napoca, Romania
| | - Andreea Elena Bodoki
- Department of General and Inorganic Chemistry, "Iuliu Hatieganu" University of Medicine and Pharmacy, 400010 Cluj-Napoca, Romania
| | - Bogdan-Cezar Iacob
- Department of Analytical Chemistry, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400349 Cluj-Napoca, Romania
| | - Ede Bodoki
- Department of Analytical Chemistry, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400349 Cluj-Napoca, Romania
| | - Ovidiu Samoilă
- Department of Ophthalmology, "Iuliu Hatieganu" University of Medicine & Pharmacy, 400006 Cluj-Napoca, Romania
| |
Collapse
|
9
|
Löscher M, Seiz C, Hurst J, Schnichels S. Topical Drug Delivery to the Posterior Segment of the Eye. Pharmaceutics 2022; 14:pharmaceutics14010134. [PMID: 35057030 PMCID: PMC8779621 DOI: 10.3390/pharmaceutics14010134] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/22/2021] [Accepted: 12/28/2021] [Indexed: 02/07/2023] Open
Abstract
Topical drug delivery to the posterior segment of the eye is a very complex challenge. However, topical delivery is highly desired, to achieve an easy-to-use treatment option for retinal diseases. In this review, we focus on the drug characteristics that are relevant to succeed in this challenge. An overview on the ocular barriers that need to be overcome and some relevant animal models to study ocular pharmacokinetics are given. Furthermore, a summary of substances that were able to reach the posterior segment after eye drop application is provided, as well as an outline of investigated delivery systems to improve ocular drug delivery. Some promising results of substances delivered to the retina suggest that topical treatment of retinal diseases might be possible in the future, which warrants further research.
Collapse
|
10
|
Del Amo EM, Hammid A, Tausch M, Toropainen E, Sadeghi A, Valtari A, Puranen J, Reinisalo M, Ruponen M, Urtti A, Sauer A, Honkakoski P. Ocular metabolism and distribution of drugs in the rabbit eye: Quantitative assessment after intracameral and intravitreal administrations. Int J Pharm 2021; 613:121361. [PMID: 34896561 DOI: 10.1016/j.ijpharm.2021.121361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/02/2021] [Accepted: 12/04/2021] [Indexed: 10/19/2022]
Abstract
Quantitation of ocular drug metabolism is important, but only sparse data is currently available. Herein, the pharmacokinetics of four drugs, substrates of metabolizing enzymes, was investigated in albino rabbit eyes after intracameral and intravitreal administrations. Acetaminophen, brimonidine, cefuroxime axetil, and sunitinib and their corresponding metabolites were quantitated in the cornea, iris-ciliary body, aqueous humor, lens, vitreous humor, and neural retina with LC-MS/MS analytics. Non-compartmental analysis was employed to estimate the pharmacokinetic parameters of the parent drugs and metabolites. The area under the curve (AUC) values of metabolites were 12-70 times lower than the AUC values of the parent drugs in the tissues with the highest enzymatic activity. The ester prodrug cefuroxime axetil was an exception because it was efficiently and quantitatively converted to cefuroxime in the ocular tissues. In contrast to the liver, sulfotransferases, aldehyde oxidase, and cytochrome P450 3A activities were low in the eye and they had negligible impact on ocular drug clearance. With the exception of esterase substrates, metabolism seems to be a minor player in ocular pharmacokinetics. However, metabolites might contribute to ocular toxicity, and drug metabolism in various eye tissues should be investigated and understood thoroughly.
Collapse
Affiliation(s)
- Eva M Del Amo
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland.
| | - Anam Hammid
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | | | - Elisa Toropainen
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Amir Sadeghi
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Annika Valtari
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Jooseppi Puranen
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Mika Reinisalo
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Marika Ruponen
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| | - Arto Urtti
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland; University of Helsinki, Faculty of Pharmacy, Drug Research Program, Yliopistonkatu 3, 00014 Helsinki, Finland; Saint-Petersburg State University, Institute of Chemistry, Universitetskiy Prospekt, 26, Petergoff 198504, Russian Federation
| | - Achim Sauer
- Department of Drug Discovery Sciences, Boehringer Ingelheim Pharma GmbH & Co. KG, 88397 Biberach, Germany
| | - Paavo Honkakoski
- University of Eastern Finland, School of Pharmacy, Biopharmaceutics, Yliopistonranta 1, 70210 Kuopio, Finland
| |
Collapse
|
11
|
Brown GT, Karth PA, Hunter AA. Novel Postoperative Dropless Protocol for Micro-Incision Vitrectomy Surgery. Ophthalmic Surg Lasers Imaging Retina 2021; 52:587-591. [PMID: 34766851 DOI: 10.3928/23258160-20211014-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND OBJECTIVE To evaluate the outcomes of a novel postoperative dropless protocol for 25-gauge and 27-gauge micro-incision vitrectomy surgery (MIVS). PATIENTS AND METHODS The institutional review board approved a single-center, retrospective study. A total of 493 surgeries were identified, and 451 cases from 369 patients met eligibility criteria. Instead of pre- or postoperative drops, patients were given a novel postoperative dropless protocol consisting of subconjunctival injections of a 1:1 cefazolin:dexamethasone mix at each sclerotomy and intravitreally, and injection of posterior sub-Tenon's Kenalog. Primary outcome measure was cases of postoperative endophthalmitis. RESULTS There was one presumed case of endophthalmitis. Anterior chamber paracentesis sample was negative for culture and Gram stain. For all patients, mean logMAR best-corrected visual acuity improved from 0.65 (±0.69) to 0.57 (±0.61) postoperatively (P = 0.004). Mean intraocular pressure increased from 14.5 (±4.3) to 15.5 (±4.8) postoperatively (P < 0.001). Mean follow-up was 96 days. CONCLUSION This novel postoperative dropless protocol could potentially be a convenient alternative to topical eye drops for patients undergoing MIVS, but further study is required to establish its safety. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:587-592.].
Collapse
|
12
|
Burhan AM, Klahan B, Cummins W, Andrés-Guerrero V, Byrne ME, O’Reilly NJ, Chauhan A, Fitzhenry L, Hughes H. Posterior Segment Ophthalmic Drug Delivery: Role of Muco-Adhesion with a Special Focus on Chitosan. Pharmaceutics 2021; 13:1685. [PMID: 34683978 PMCID: PMC8539343 DOI: 10.3390/pharmaceutics13101685] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/24/2021] [Accepted: 09/27/2021] [Indexed: 01/04/2023] Open
Abstract
Posterior segment eye diseases (PSEDs) including age macular degeneration (AMD) and diabetic retinopathy (DR) are amongst the major causes of irreversible blindness worldwide. Due to the numerous barriers encountered, highly invasive intravitreal (IVT) injections represent the primary route to deliver drugs to the posterior eye tissues. Thus, the potential of a more patient friendly topical route has been widely investigated. Mucoadhesive formulations can decrease precorneal clearance while prolonging precorneal residence. Thus, they are expected to enhance the chances of adherence to corneal and conjunctival surfaces and as such, enable increased delivery to the posterior eye segment. Among the mucoadhesive polymers available, chitosan is the most widely explored due to its outstanding mucoadhesive characteristics. In this review, the major PSEDs, their treatments, barriers to topical delivery, and routes of topical drug absorption to the posterior eye are presented. To enable the successful design of mucoadhesive ophthalmic drug delivery systems (DDSs), an overview of mucoadhesion, its theory, characterization, and considerations for ocular mucoadhesion is given. Furthermore, chitosan-based DDs that have been explored to promote topical drug delivery to the posterior eye segment are reviewed. Finally, challenges of successful preclinical to clinical translation of these DDSs for posterior eye drug delivery are discussed.
Collapse
Affiliation(s)
- Ayah Mohammad Burhan
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| | - Butsabarat Klahan
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| | - Wayne Cummins
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| | - Vanessa Andrés-Guerrero
- Innovation, Therapy and Pharmaceutical Development in Ophthalmology (InnOftal) Research Group, Department of Pharmaceutics and Food Technology, Faculty of Pharmacy, Sanitary Research Institute of the San Carlos Clinical Hospital (IdISSC), Complutense University of Madrid, 28040 Madrid, Spain;
| | - Mark E. Byrne
- Biomimetic & Biohybrid Materials, Biomedical Devices & Drug Delivery Laboratories, Department of Biomedical Engineering, Rowan University, Glassboro, NJ 08028, USA;
| | - Niall J. O’Reilly
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| | - Anuj Chauhan
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, CO 80401, USA;
| | - Laurence Fitzhenry
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| | - Helen Hughes
- Ocular Therapeutics Research Group, Pharmaceutical and Molecular Biotechnology Research Centre, Waterford Institute of Technology, X91 K0EK Waterford, Ireland; (W.C.); (N.J.O.); (L.F.); (H.H.)
| |
Collapse
|
13
|
Tamhane M, Luu KT, Attar M. Ocular Pharmacokinetics of Brimonidine Drug Delivery System in Monkeys and Translational Modeling for Selection of Dose and Frequency in Clinical Trials. J Pharmacol Exp Ther 2021; 378:207-214. [PMID: 34210753 DOI: 10.1124/jpet.120.000483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 06/28/2021] [Indexed: 01/07/2023] Open
Abstract
Brimonidine, a selective α 2-adrenoceptor agonist, displays putative retinal cyto- and neuroprotective activity in vitro and in vivo. An intravitreal sustained-release brimonidine implant, Brimonidine Posterior Segment Drug Delivery System (brimonidine DDS), allowing targeted drug delivery to the retina has been developed for potential clinical application. This study evaluates the in vivo posterior segment pharmacokinetics of brimonidine DDS implant in the monkey eye and applies translational pharmacokinetic modeling to predict tissue exposure in the human eye. Anesthetized cynomolgus monkeys received a single intravitreal injection of brimonidine DDS 400 µg implant before removal of study eyes at days 7, 30, 60, 92, 120, and 150 postimplant (three to four animals per time point) for assay of brimonidine in aqueous humor, vitreous, and retina samples. Brimonidine concentrations in the human eye were modeled using a linear, three-compartment model assuming bidirectional distribution to/from the aqueous humor and retina and elimination from the aqueous humor. Monkey tissue volumes were scaled up to human values; intercompartmental and elimination rate constants were assumed to be identical in the two species. Modeling and simulations were performed using NONMEM v. 7.3, R 3.5.1. Brimonidine exposure was highest in the monkey vitreous and retina; concentrations in the central (macula) and peripheral retina were maintained at high levels (>100 ng/g) for 3 to 4 months. Simulated brimonidine concentration-time profiles in human macula indicated that brimonidine DDS 400 µg implant would deliver effective drug concentrations (20.7‒82.2 ng/g, based on animal pharmacology) for approximately 3 months. Accordingly, administration of the 400 µg implant at 3-month intervals is recommended. SIGNIFICANCE STATEMENT: Brimonidine, an α 2-adrenoceptor agonist, is cyto- and neuroprotective in animal models of retinal/optic nerve injury. Brimonidine Posterior Segment Drug Delivery System (brimonidine DDS) is an intravitreal sustained-release implant with potential ophthalmological applications. This study explores the pharmacokinetics of brimonidine DDS 400 µg implant in the monkey eye and uses compartmental modeling to predict human ocular tissue exposure. Targeted retinal brimonidine delivery from vitreous was demonstrated in monkeys. Simulated tissue concentration-time profiles indicated persistence of pharmacologically effective brimonidine concentrations for ≈3 months in human retina.
Collapse
|
14
|
Rajagopalan L, Ghosn C, Tamhane M, Almazan A, Andrews-Jones L, Kulkarni A, Christie LA, Burke J, López FJ, Engles M. A nonhuman primate model of blue light-induced progressive outer retina degeneration showing brimonidine drug delivery system-mediated cyto- and neuroprotection. Exp Eye Res 2021; 209:108678. [PMID: 34153289 DOI: 10.1016/j.exer.2021.108678] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/09/2021] [Accepted: 06/14/2021] [Indexed: 11/26/2022]
Abstract
Geographic atrophy (GA) is an advanced form of age-related macular degeneration (AMD) characterized by atrophy of the retinal pigment epithelium (RPE), loss of photoreceptors, and disruption of choriocapillaris. Excessive light exposure is toxic to the retina and is a known risk factor for AMD. We first investigated the effects of blue light-induced phototoxicity on RPE and photoreceptors in nonhuman primates (NHPs, a model of progressive retinal degeneration) and then evaluated the potential cyto- and neuroprotective effects of the brimonidine drug delivery system (Brimo DDS). In the first set of experiments related to model development, parafoveal lesions of varying severity were induced using blue light irradiation of the retina of cynomolgus monkeys to evaluate the level of phototoxicity in the RPE and photoreceptors. RPE damage was assessed using fundus autofluorescence imaging to quantify areas of hypofluorescence, while thinning of the outer nuclear layer (ONL, photoreceptor nuclei) was quantified using optical coherence tomography (OCT). Photoreceptor function was assessed using multifocal electroretinography (mfERG). RPE damage progressively increased across all lesion severities from 2 to 12 weeks, as did the extent of ONL thinning. Lesions of high severity continued to show reduction in mfERG amplitude, reaching a statistically significant maximum reduction at 12 weeks. Collectively, the first set of experiments showed that blue light irradiation of the NHP eye resulted in progressive retinal degeneration identified by damage to RPE, ONL thinning, and disrupted photoreceptor function - hallmarks of GA in humans. We then used the model to evaluate the cyto- and neuroprotective effects of Brimo DDS, administered as a therapeutic after allowing the lesions to develop for 5 weeks. Placebo DDS or Brimo DDS were administered intravitreally and a set of untreated animals were used as an additional control. In the placebo DDS group, hypofluorescence area continued to increase from baseline, indicating progressive RPE damage, while progression was significantly slowed in eyes receiving Brimo DDS. Likewise, ONL thinning continued to progress over time in eyes that received the placebo DDS, but was reduced in Brimo DDS-treated eyes. Pharmacologically relevant brimonidine concentrations were sustained in the retina for up to 26 weeks following Brimo DDS administration. In summary, Brimo DDS demonstrated cyto- and neuroprotective effects in a novel NHP GA model of progressive retinal degeneration.
Collapse
Affiliation(s)
| | - Corine Ghosn
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - Mitalee Tamhane
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - Alexandra Almazan
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | | | - Ashutosh Kulkarni
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - Lori-Ann Christie
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - James Burke
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - Francisco J López
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA
| | - Michael Engles
- Allergan (an AbbVie company), 2525 Dupont Drive, Irvine, CA, 92612, USA.
| |
Collapse
|
15
|
da Silva PHR, Cunha Júnior ADS, Pianetti GA, Fernandes C. Chromatographic bioanalysis of antiglaucoma drugs in ocular tissues. J Chromatogr B Analyt Technol Biomed Life Sci 2021; 1166:122388. [PMID: 33578274 DOI: 10.1016/j.jchromb.2020.122388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 09/11/2020] [Accepted: 09/24/2020] [Indexed: 10/23/2022]
Abstract
Glaucoma is a heterogeneous group of multifactorial optic neuropathies and the leading cause of irreversible blindness and visual impairment. Epidemiological data has estimated that in 2020 there will be more than 80 million individuals affected by the disease worldwide. Nowadays, intraocular pressure (IOP) lowering is carried out mainly by pharmacotherapy, with different drugs. The study of ocular pharmacokinetics of antiglaucoma drugs, crucial for better understanding of ocular distribution, bioavailability, and pharmacodynamic parameters, can benefit the development of antiglaucoma drugs or formulations. Bioanalysis of drugs in ocular matrices is still underestimated, since it is challenging and rarely performed. Therefore, this review summarized the chromatographic methods employed for the quantification of several antiglaucoma drugs in different ocular matrices, discussing bioanalytical steps, such as sample preparation, separation, and detection. Animals and matrices as well as the challenges faced in ocular bioanalysis were also discussed. Ocular bioanalysis has been performed mainly in rabbits, the most adequate animal model for ocular studies. The matrix most used is aqueous humor, because it is cleaner and easier to sample. Sample preparation was carried out primarily employing classic techniques, such as liquid-liquid extraction, protein precipitation, and solid-phase extraction, with conventional solvents and sorbents. Chromatographic separation was achieved predominantly by reversed-phase liquid chromatography. Ultraviolet spectrophotometry and tandem mass spectrometry prevailed for detection, although other techniques, such as fluorimetry, have also been used. It was evidenced that more efforts must be directed towards miniaturized, eco-friendly, and non-terminal sampling for sample preparation. In its turn, ultra high-performance liquid chromatography and mass spectrometry should gain prominence in ocular bioanalysis for separation and detection, respectively, since it combines high separation capacity with selectivity and sensitivity, in addition to being an environmental friendly approach.
Collapse
Affiliation(s)
- Pedro Henrique Reis da Silva
- Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Armando da Silva Cunha Júnior
- Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Gerson Antônio Pianetti
- Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil
| | - Christian Fernandes
- Departamento de Produtos Farmacêuticos, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Av. Pres. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
| |
Collapse
|
16
|
A Topical Formulation of Melatoninergic Compounds Exerts Strong Hypotensive and Neuroprotective Effects in a Rat Model of Hypertensive Glaucoma. Int J Mol Sci 2020; 21:ijms21239267. [PMID: 33291737 PMCID: PMC7730513 DOI: 10.3390/ijms21239267] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/23/2020] [Accepted: 12/02/2020] [Indexed: 02/08/2023] Open
Abstract
Melatonin is of great importance for regulating several eye processes, including pressure homeostasis. Melatonin in combination with agomelatine has been recently reported to reduce intraocular pressure (IOP) with higher efficacy than each compound alone. Here, we used the methylcellulose (MCE) rat model of hypertensive glaucoma, an optic neuropathy characterized by the apoptotic death of retinal ganglion cells (RGCs), to evaluate the hypotensive and neuroprotective efficacy of an eye drop nanomicellar formulation containing melatonin/agomelatine. Eye tissue distribution of melatonin/agomelatine in healthy rats was evaluated by HPLC/MS/MS. In the MCE model, we assessed by tonometry the hypotensive efficacy of melatonin/agomelatine. Neuroprotection was revealed by electroretinography; by levels of inflammatory and apoptotic markers; and by RGC density. The effects of melatonin/agomelatine were compared with those of timolol (a beta blocker with prevalent hypotensive activity) or brimonidine (an alpha 2 adrenergic agonist with potential neuroprotective efficacy), two drugs commonly used to treat glaucoma. Both melatonin and agomelatine penetrate the posterior segment of the eye. In the MCE model, IOP elevation was drastically reduced by melatonin/agomelatine with higher efficacy than that of timolol or brimonidine. Concomitantly, gliosis-related inflammation and the Bax-associated apoptosis were partially prevented, thus leading to RGC survival and recovered retinal dysfunction. We suggest that topical melatoninergic compounds might be beneficial for ocular health.
Collapse
|
17
|
Rimpelä AK, Garneau M, Baum-Kroker KS, Schönberger T, Runge F, Sauer A. Quantification of Drugs in Distinctly Separated Ocular Substructures of Albino and Pigmented Rats. Pharmaceutics 2020; 12:pharmaceutics12121174. [PMID: 33276439 PMCID: PMC7760391 DOI: 10.3390/pharmaceutics12121174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 11/27/2020] [Accepted: 11/28/2020] [Indexed: 11/16/2022] Open
Abstract
The rat is a commonly used species in ocular drug research. Detailed methods of separating rat ocular tissues have not been described in literature. To understand the intraocular drug distribution, we developed a robust method for the separation of individual anterior and posterior substructures of pigmented Brown Norway (BN) and albino Wistar Han (WH) rat eyes, followed by quantification of drug concentration in these substructures. A short formalin incubation, which did not interfere with drug quantification, enabled the preservation of individual tissue sections while minimizing cross-tissue contamination, as demonstrated by histological analysis. Following oral administration, we applied the tissue separation method, in order to determine the ocular concentrations of dexamethasone and levofloxacin, as well as two in-house molecules BI 113823 and BI 1026706, compounds differing in their melanin binding. The inter-individual variability in tissue partitioning coefficients (Kp) was low, demonstrating the reproducibility of the separation method. Kp values of individual tissues varied up to 100-fold in WH and up to 46,000-fold in BN rats highlighting the importance of measuring concentration directly from the ocular tissue of interest. Additionally, clear differences were observed in the BN rat tissue partitioning compared to the WH rat. Overall, the developed method enables a reliable determination of small molecule drug concentrations in ocular tissues to support ocular drug research and development.
Collapse
|
18
|
Varela-Fernández R, Díaz-Tomé V, Luaces-Rodríguez A, Conde-Penedo A, García-Otero X, Luzardo-Álvarez A, Fernández-Ferreiro A, Otero-Espinar FJ. Drug Delivery to the Posterior Segment of the Eye: Biopharmaceutic and Pharmacokinetic Considerations. Pharmaceutics 2020; 12:E269. [PMID: 32188045 PMCID: PMC7151081 DOI: 10.3390/pharmaceutics12030269] [Citation(s) in RCA: 177] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Revised: 03/06/2020] [Accepted: 03/11/2020] [Indexed: 01/22/2023] Open
Abstract
The treatment of the posterior-segment ocular diseases, such as age-related eye diseases (AMD) or diabetic retinopathy (DR), present a challenge for ophthalmologists due to the complex anatomy and physiology of the eye. This specialized organ is composed of various static and dynamic barriers that restrict drug delivery into the target site of action. Despite numerous efforts, effective intraocular drug delivery remains unresolved and, therefore, it is highly desirable to improve the current treatments of diseases affecting the posterior cavity. This review article gives an overview of pharmacokinetic and biopharmaceutics aspects for the most commonly-used ocular administration routes (intravitreal, topical, systemic, and periocular), including information of the absorption, distribution, and elimination, as well as the benefits and limitations of each one. This article also encompasses different conventional and novel drug delivery systems designed and developed to improve drug pharmacokinetics intended for the posterior ocular segment treatment.
Collapse
Affiliation(s)
- Rubén Varela-Fernández
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Clinical Neurosciences Group, University Clinical Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Victoria Díaz-Tomé
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Clinical Pharmacology Group, University Clinical Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Andrea Luaces-Rodríguez
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Clinical Pharmacology Group, University Clinical Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Andrea Conde-Penedo
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Paraquasil Group, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Xurxo García-Otero
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Molecular Imaging Group. University Clinical Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Asteria Luzardo-Álvarez
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Paraquasil Group, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Anxo Fernández-Ferreiro
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Clinical Pharmacology Group, University Clinical Hospital, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| | - Francisco J. Otero-Espinar
- Department of Pharmacology, Pharmacy and Pharmaceutical Technology, University of Santiago de Compostela (USC), Campus vida, 15782 Santiago de Compostela, Spain; (R.V.-F.); (V.D.-T.); (A.L.-R.); (A.C.-P.); (X.G.-O.); (A.L.-Á.)
- Paraquasil Group, Health Research Institute of Santiago de Compostela (IDIS), Travesía da Choupana s/n, 15706 Santiago de Compostela, Spain
| |
Collapse
|
19
|
Matteucci A, Ricceri L, Fabbri A, Fortuna A, Travaglione S, Guidotti M, Martinelli A, Villa M, Pricci F, Maroccia Z, Campana G, Malchiodi-Albedi F, Fiorentini C, Loizzo S. Eye Drop Instillation of the Rac1 Modulator CNF1 Attenuates Retinal Gliosis and Ameliorates Visual Performance in a Rat Model of Hypertensive Retinopathy. Neuroscience 2019; 411:119-129. [PMID: 31128161 DOI: 10.1016/j.neuroscience.2019.05.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/15/2022]
Abstract
In hypertensive retinopathy, the retinal damage due to high blood pressure is accompanied by increased expression of Glial Fibrillary Acidic Protein (GFAP), which indicates a role of neuroinflammatory processes in such a retinopathy. Proteins belonging to the Rho GTPase family, particularly Rac1, are involved in the activation of Müller glia and in the progression of photoreceptor degeneration, and may thus represent a novel candidate for therapeutic intervention following central nervous system inflammation. In this paper, we have observed that topical administration as eye drops of Cytotoxic Necrotizing Factor 1 (CNF1), a Rho GTPase modulator, surprisingly improves electrophysiological and behavioral visual performances in aged spontaneously hypertensive rats. Furthermore, such functional improvement is accompanied by a reduction of Rac1 activity and retinal GFAP expression. Our results suggest that Rac1 inhibition through CNF1 topical administration may represent a new strategy to target retinal gliosis.
Collapse
Affiliation(s)
- Andrea Matteucci
- National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Laura Ricceri
- Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Alessia Fabbri
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Andrea Fortuna
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Sara Travaglione
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Marco Guidotti
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Andrea Martinelli
- National Centre for Animal Research and Welfare, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Marika Villa
- Department of Cardiovascular, Dysmetabolic and Endocrine-Metabolic Diseases, and Ageing, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Flavia Pricci
- Department of Cardiovascular, Dysmetabolic and Endocrine-Metabolic Diseases, and Ageing, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Zaira Maroccia
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Gabriele Campana
- Department of Pharmacy and Biotechnology, University of Bologna, Via Zamboni, 33, Bologna, Italy
| | - Fiorella Malchiodi-Albedi
- Centre for Behavioural Sciences and Mental Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
| | - Carla Fiorentini
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy; Association for Research on Integrative Oncology Therapies (ARTOI), Rome, Italy
| | - Stefano Loizzo
- Italian Center for Global Health, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy.
| |
Collapse
|
20
|
Effect of Solution pH on Distribution of Ophthalmically Administered Brimonidine in Posterior Ocular Tissues in Pigmented Rabbits. Ophthalmol Ther 2019; 8:271-277. [PMID: 30891685 PMCID: PMC6514203 DOI: 10.1007/s40123-019-0180-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Indexed: 10/27/2022] Open
Abstract
INTRODUCTION Brimonidine bioavailability in the aqueous humor depends on the solution pH following topical administration. The purpose of this study was to investigate the effect of solution pH on brimonidine distribution in the posterior ocular tissues in pigmented rabbits. METHODS The anterior retina/choroid, posterior retina/choroid, and vitreous body of pigmented rabbits were collected 0.67, 1.5, 3, 6, 12, 24, 168, and 360 h after the administration of a single topical dose of 0.2% brimonidine tartrate ophthalmic solution, pH 6.4 (Alphagan®; Allergan Inc., Irvine, CA, USA). Brimonidine concentrations in these tissues were quantified using liquid chromatography/tandem mass spectrometry. Pharmacokinetic parameters were determined using noncompartmental analysis, and the results were compared with tissues from eyes administered 0.1% brimonidine tartrate ophthalmic solution, pH 7.3 (Aiphagan®; Senju Pharmaceutical Co., Ltd., Osaka, Japan) in our previous study conducted using the same procedure. RESULTS Topically applied brimonidine was distributed rapidly into the posterior tissues of the eye after a single ophthalmic administration of the 0.2% ophthalmic solution. The areas under the curve from time 0 to 360 h following dosing with the 0.2% ophthalmic solution were 500,000, 14,300, and 28.7 ng h/g in the anterior and posterior retina/choroid, and vitreous body, respectively. CONCLUSION The differences in the areas under the curve between two ophthalmic solutions were less than the difference in drug concentrations between these two products in any tissues. This finding indicates that the change in the solution pH from 6.4 to 7.3 increases brimonidine bioavailability into the posterior ocular tissues similarly as into the aqueous humor. FUNDING Senju Pharmaceutical Co., Ltd.
Collapse
|
21
|
Dumouchel JL, Chemuturi N, Milton MN, Camenisch G, Chastain J, Walles M, Sasseville V, Gunduz M, Iyer GR, Argikar UA. Models and Approaches Describing the Metabolism, Transport, and Toxicity of Drugs Administered by the Ocular Route. Drug Metab Dispos 2018; 46:1670-1683. [DOI: 10.1124/dmd.118.082974] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/10/2018] [Indexed: 11/22/2022] Open
|
22
|
Yamaguchi H, Takezawa T. Fabrication of a Corneal Model Composed of Corneal Epithelial and Endothelial Cells via a Collagen Vitrigel Membrane Functioned as an Acellular Stroma and Its Application to the Corneal Permeability Test of Chemicals. Drug Metab Dispos 2018; 46:1684-1691. [PMID: 29844140 DOI: 10.1124/dmd.118.080820] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2018] [Accepted: 05/21/2018] [Indexed: 11/22/2022] Open
Abstract
A collagen vitrigel membrane (CVM) we developed can function as both a scaffold for cells and a pathway for chemicals. To extrapolate the corneal permeability of chemicals in vivo, we proposed six corneal models using the CVM. Thin and thick CVMs were used as models for Bowman's membrane (BM) and an acellular stroma (AS), respectively. Models for a corneal epithelium (CEpi), a CEpi-AS, a CEpi-endothelium (Endo), and a CEpi-AS-Endo were fabricated by culturing corneal epithelial cells and/or corneal endothelial cells on the surface of CVMs. Subsequently, the permeability coefficient (Papp) value of each model was calculated using five chemicals with different molecular radii; cyanocobalamin and four fluorescein isothiocyanate-dextrans (FD) (FD-4, FD-10, FD-20, and FD-40). The slopes of Papp versus molecular radii of those chemicals in the both BM and AS models were almost similar to data using an excised rabbit corneal stroma. The ratios of Papp values in models for BM, CEpi, and CEpi-Endo against those in data using an excised rabbit cornea were calculated as 75.4-fold, 6.4-fold, and 4.5-fold for FD-4, and 38.7-fold, 10.0-fold, and 4.2-fold for FD-10, respectively. Similarly, those in models for AS, CEpi-AS, and CEpi-AS-Endo were calculated as 26.1-fold, 2.5-fold, and 0.6-fold for FD-4, and 26.1-fold, 1.5-fold, and 0.6-fold for FD-10, respectively. These results suggest that the CEpi-AS-Endo model with both the barrier function of corneal cell layers and the diffusion capacity of chemicals in thick CVM is most appropriate for extrapolating the corneal permeability of chemicals in vivo.
Collapse
Affiliation(s)
- Hiroyuki Yamaguchi
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (H.Y., T.T.); and Isehara Research Laboratory, Technology and Development Division, Kanto Chemical Co., Inc., Isehara, Kanagawa, Japan (H.Y.)
| | - Toshiaki Takezawa
- Division of Biotechnology, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, Tsukuba, Ibaraki, Japan (H.Y., T.T.); and Isehara Research Laboratory, Technology and Development Division, Kanto Chemical Co., Inc., Isehara, Kanagawa, Japan (H.Y.)
| |
Collapse
|
23
|
Han X, Liu Y, Kam WR, Sullivan DA. Effect of brimonidine, an α2 adrenergic agonist, on human meibomian gland epithelial cells. Exp Eye Res 2018; 170:20-28. [PMID: 29452108 DOI: 10.1016/j.exer.2018.02.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/09/2018] [Accepted: 02/12/2018] [Indexed: 01/15/2023]
Abstract
We recently discovered that the anti-glaucoma pharmaceuticals timolol, a β adrenergic antagonist, and pilocarpine, a cholinergic compound, negatively influence the morphology, proliferative capacity and survival of human meibomian gland epithelial cells (HMGECs). We hypothesize that another class of anti-glaucoma drugs, the α2 adrenergic agonists, also acts directly on HMGECs to affect their structure and function. We tested this hypothesis. Immortalized (i) HMGECs were cultured with brimonidine, as well as clonidine (α2 agonist), phenylephrine (α1 agonist), RX821002 (inverse α2 agonist) and MK912 (neutral α2 agonist) for up to 7 days. Cells were counted with a hemocytometer, and evaluated for morphology, signaling pathway activity, protein biomarker expression, and the accumulation of neutral lipids, phospholipids and lysosomes. Our findings demonstrate that brimondine treatment induces a dose-dependent decrease in Akt signaling and proliferation of iHMGECs. In contrast, brimonidine also promotes a dose-dependent differentiation of iHMGECs, including an increase in neutral lipid, phospholipid and lysosome levels. These effects were paralleled by an inhibition of p38 signaling, and duplicated by cellular exposure to clonidine, but not phenylephrine. Brimonidine also enhanced the cellular content of sterol regulatory binding protein-1, a master regulator of lipid synthesis. Of particular interest, the putative α2 antagonists, RX821002 and MK912, did not interfere with brimonidine action, but rather stimulated IHMGEC differentiation. Our results support our hypothesis and demonstrate that α2 adrenergic agonists act directly on iHMGECs. However, these compounds do not elicit an overall negative effect. Rather, the α2 agonists promote the differentiation of iHMGECs.
Collapse
Affiliation(s)
- Xi Han
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA; Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yang Liu
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Wendy R Kam
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - David A Sullivan
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
| |
Collapse
|
24
|
Grove KJ, Kansara V, Prentiss M, Long D, Mogi M, Kim S, Rudewicz PJ. Application of Imaging Mass Spectrometry to Assess Ocular Drug Transit. SLAS DISCOVERY 2017; 22:1239-1245. [PMID: 28787579 DOI: 10.1177/2472555217724780] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) is becoming an important technology to determine the distribution of drugs and their metabolites in the tissue of preclinical species after dosing. Interest in IMS is growing in the ophthalmology field, but little work to this point has been done to investigate ocular drug transit using this technology. Information on where and how a drug is distributing through the eye is important in understanding efficacy and whether it is reaching the desired target tissue. For this study, ocular distribution of brimonidine was investigated in rabbits following topical administration. Brimonidine has been shown to lower intraocular pressure and is approved to treat glaucoma, the second leading cause of blindness in the world. We have developed IMS methods to assess transit of topically administered brimonidine from the anterior to the posterior segment of rabbit eyes. Using IMS, brimonidine was detected in the cornea, aqueous humor, iris, and posterior segments of the eye. The distribution of brimonidine suggests that the route of transit following topical administration is mainly through the uvea-scleral route. This study demonstrates that IMS can be applied to assess ocular transit and distribution of topically administered drugs.
Collapse
Affiliation(s)
- Kerri J Grove
- 1 Novartis Institutes for BioMedical Research, Emeryville, CA, USA
| | - Viral Kansara
- 2 Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Melissa Prentiss
- 2 Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Debby Long
- 2 Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Muneto Mogi
- 2 Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Sean Kim
- 2 Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | |
Collapse
|
25
|
Szigiato AA, Podbielski DW, Ahmed IIK. Sustained drug delivery for the management of glaucoma. EXPERT REVIEW OF OPHTHALMOLOGY 2017. [DOI: 10.1080/17469899.2017.1280393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
| | - Dominik W. Podbielski
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada
| | - Iqbal Ike K. Ahmed
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
26
|
Abstract
Although the fundamental concepts of pharmacokinetics remain the same, ocular pharmacokinetics has its own challenges due to the uniqueness of barrier properties posed by various ocular tissues and its growing complexity with different routes of ocular administration. A thorough understanding of the barrier nature will aid in tailoring a drug or its carrier's physicochemical properties to its advantage. In order to deliver the right payload of a drug at the target site, various approaches can be taken to leverage the pharmacokinetics that includes molecular design based on desirable physicochemical properties, formulation approaches, and alternative routes of administration. In this chapter, a brief overview of the barrier properties with respect to various routes of administration is presented along with the physicochemical properties that influence the pharmacokinetics of ocular drugs. Recent advances in ocular pharmacokinetics are discussed in addition to new perspectives in interpreting existing data.
Collapse
Affiliation(s)
- Chandrasekar Durairaj
- Pfizer - Clinical Pharmacology, 10555 Science Center Drive, San Diego, CA, 92121, USA.
| |
Collapse
|
27
|
Del Amo EM, Rimpelä AK, Heikkinen E, Kari OK, Ramsay E, Lajunen T, Schmitt M, Pelkonen L, Bhattacharya M, Richardson D, Subrizi A, Turunen T, Reinisalo M, Itkonen J, Toropainen E, Casteleijn M, Kidron H, Antopolsky M, Vellonen KS, Ruponen M, Urtti A. Pharmacokinetic aspects of retinal drug delivery. Prog Retin Eye Res 2016; 57:134-185. [PMID: 28028001 DOI: 10.1016/j.preteyeres.2016.12.001] [Citation(s) in RCA: 403] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/25/2016] [Accepted: 12/01/2016] [Indexed: 12/14/2022]
Abstract
Drug delivery to the posterior eye segment is an important challenge in ophthalmology, because many diseases affect the retina and choroid leading to impaired vision or blindness. Currently, intravitreal injections are the method of choice to administer drugs to the retina, but this approach is applicable only in selected cases (e.g. anti-VEGF antibodies and soluble receptors). There are two basic approaches that can be adopted to improve retinal drug delivery: prolonged and/or retina targeted delivery of intravitreal drugs and use of other routes of drug administration, such as periocular, suprachoroidal, sub-retinal, systemic, or topical. Properties of the administration route, drug and delivery system determine the efficacy and safety of these approaches. Pharmacokinetic and pharmacodynamic factors determine the required dosing rates and doses that are needed for drug action. In addition, tolerability factors limit the use of many materials in ocular drug delivery. This review article provides a critical discussion of retinal drug delivery, particularly from the pharmacokinetic point of view. This article does not include an extensive review of drug delivery technologies, because they have already been reviewed several times recently. Instead, we aim to provide a systematic and quantitative view on the pharmacokinetic factors in drug delivery to the posterior eye segment. This review is based on the literature and unpublished data from the authors' laboratory.
Collapse
Affiliation(s)
- Eva M Del Amo
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Anna-Kaisa Rimpelä
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Emma Heikkinen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Otto K Kari
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Eva Ramsay
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Tatu Lajunen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Mechthild Schmitt
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Laura Pelkonen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Madhushree Bhattacharya
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Dominique Richardson
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Astrid Subrizi
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Tiina Turunen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Mika Reinisalo
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Jaakko Itkonen
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Elisa Toropainen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Marco Casteleijn
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Heidi Kidron
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | - Maxim Antopolsky
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland
| | | | - Marika Ruponen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Arto Urtti
- Centre for Drug Research, Division of Pharmaceutical Biosciences, University of Helsinki, Helsinki, Finland; School of Pharmacy, University of Eastern Finland, Kuopio, Finland.
| |
Collapse
|
28
|
Shinno K, Kurokawa K, Kozai S, Kawamura A, Inada K, Tokushige H. The Relationship of Brimonidine Concentration in Vitreous Body to the Free Concentration in Retina/Choroid Following Topical Administration in Pigmented Rabbits. Curr Eye Res 2016; 42:748-753. [DOI: 10.1080/02713683.2016.1238941] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
| | | | - Seiko Kozai
- Senju Pharmaceutical Co., Ltd., Osaka, Japan
| | | | | | | |
Collapse
|
29
|
Mathematical modelling of brimonidine absorption via topical delivery of microparticle formulations to the eye. J IND ENG CHEM 2016. [DOI: 10.1016/j.jiec.2016.05.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
30
|
Osborne NN, Núñez-Álvarez C, Joglar B, Del Olmo-Aguado S. Glaucoma: Focus on mitochondria in relation to pathogenesis and neuroprotection. Eur J Pharmacol 2016; 787:127-33. [PMID: 27090928 DOI: 10.1016/j.ejphar.2016.04.032] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 03/25/2016] [Accepted: 04/14/2016] [Indexed: 12/23/2022]
Abstract
Primary open-angle glaucoma (POAG) is a common form of glaucoma in which retinal ganglion cells (RGCs) die at varying intervals. Primary open-angle glaucoma is often associated with an increased intraocular pressure (IOP), which when reduced, can slow down the progression of the disease. However, it is essential to develop better modes of treatments for glaucoma patients. In this overview, we discuss the hypothesis that RGC mitochondria are affected during the initiation of POAG, by becoming gradually weakened, but at different rates because of their specific receptor profiles. With this in mind, we argue that neuroprotection in the context of glaucoma should focus on preserving RGC mitochondrial function and suggest a number of ways by which this can theoretically be achieved. Since POAG is a chronic disease, any neuroprotective treatment strategy must be tolerated over many years. Theoretically, topically applied substances should have the fewest side effects, but it is questionable whether sufficient compounds can reach RGC mitochondria to be effective. Therefore, other delivery procedures that might result in greater concentrations of neuroprotectants reaching RGC mitochondria are being developed. Red-light therapy represents another therapeutic alternative for enhancing RGC mitochondrial functions and has the advantage of being both non-toxic and non-invasive.
Collapse
Affiliation(s)
- Neville N Osborne
- Fundación de Investigación Oftalmológica, Avda. Doctores Fernández-Vega 34, E-33012 Oviedo, Asturias, Spain.
| | - Claudia Núñez-Álvarez
- Fundación de Investigación Oftalmológica, Avda. Doctores Fernández-Vega 34, E-33012 Oviedo, Asturias, Spain
| | - Belen Joglar
- Fundación de Investigación Oftalmológica, Avda. Doctores Fernández-Vega 34, E-33012 Oviedo, Asturias, Spain
| | - Susana Del Olmo-Aguado
- Fundación de Investigación Oftalmológica, Avda. Doctores Fernández-Vega 34, E-33012 Oviedo, Asturias, Spain
| |
Collapse
|
31
|
Effect of sterilization on the physical stability of brimonidine-loaded solid lipid nanoparticles and nanostructured lipid carriers. Int J Pharm 2015; 496:976-83. [DOI: 10.1016/j.ijpharm.2015.10.043] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 10/11/2015] [Accepted: 10/12/2015] [Indexed: 11/24/2022]
|
32
|
Jung KI, Kim JH, Park CK. α2-Adrenergic modulation of the glutamate receptor and transporter function in a chronic ocular hypertension model. Eur J Pharmacol 2015; 765:274-83. [PMID: 26300392 DOI: 10.1016/j.ejphar.2015.08.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 08/19/2015] [Accepted: 08/19/2015] [Indexed: 12/13/2022]
Abstract
Excitotoxicity, glutamate-induced toxic effects to retinal ganglion cells (RGCs), is one of several mechanisms of RGC loss suggested in glaucoma. In this study, we focused on the role of glutamate transporter of glial cells as well as N-methyl-d-aspartate (NMDA) receptor with regard to glutamate toxicity in glaucoma. We also investigated whether α2-adrenoceptor activation could modulate glutamate transporters and NMDA receptors in a chronic ocular hypertension model. Brimonidine 0.15% was administered topically to the eyes of experimental glaucoma and control animals twice daily. After 8 weeks of intraocular pressure (IOP) elevation, staining with terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) revealed an increase in the ganglion cell layer, and the number of TUNEL-positive cells was reduced by brimonidine treatment (P<0.05). Animals with experimentally induced glaucoma exhibited an increase in retinal stress marker glial fibrillary acidic protein (GFAP) immunoreactivity; brimonidine treatment reduced GFAP. Excitatory amino acid transporter 1(EAAT1) expression remained stable throughout the period of chronic ocular hypertension. α2-Adrenergic treatment upregulated EAAT1 protein levels (P<0.05). NMDA receptor (GluN1) expression was stimulated by chronic elevation of IOP, and GluN1-positive cells in ganglion cell layer were co-localized with TUNEL staining. Brimonidine administration suppressed GluN1 levels (P<0.05). These results indicate that brimonidine decreased RGC apoptosis, upregulating EAAT1 and downregulating NMDA receptors. We suggest that topical brimonidine treatment may decrease the glutamate excitotoxicity through modulation of glutamate transporter and NMDA receptor in glaucoma.
Collapse
Affiliation(s)
- Kyoung In Jung
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea, Seoul, Korea
| | - Jie Hyun Kim
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea, Seoul, Korea
| | - Chan Kee Park
- Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea, Seoul, Korea.
| |
Collapse
|
33
|
Abdul Nasir NA, Agarwal P, Agarwal R, Iezhitsa I, Alyautdin R, Nukolova NN, Chekhonin VP, Mohd Ismail N. Intraocular distribution of topically applied hydrophilic and lipophilic substances in rat eyes. Drug Deliv 2015; 23:2765-2771. [PMID: 26289215 DOI: 10.3109/10717544.2015.1077292] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE Topical administration is the preferred route of drug delivery for ophthalmic ailments. However, poor permeation through ocular surface and significant systemic absorption, makes the topical drug delivery challenging. Furthermore, distribution of topically delivered drugs varies with their physicochemical properties and the type of formulation used. Hence, this study was done to understand the pattern of ocular drug distribution of topically applied hydrophilic and lipophilic substances in two different formulations. METHODS 5-Carboxyfluorescein and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate were used as representative candidates for hydrophilic and lipophilic substances, respectively. They were formulated in solution and liposomes. Single drop of either formulation containing hydrophilic or lipophilic substance was instilled topically, unilaterally to rat eyes. Subsequently, rats were sacrificed at 10, 30 and 120 min post-instillation. Eyes were cryosectioned and examined under confocal microscope to determine the fluorescence intensity in ocular tissues. RESULTS Corneal permeation of hydrophilic and lipophilic substances in both formulations peaked at 30 min post-instillation. Liposomal-lipophilic dye and non-liposomal-hydrophilic dye showed better corneal distribution. Fluorescence was absent in contralateral eyes of non-liposomal-hydrophilic dye-treated animals but was present in contralateral eyes of liposomal-hydrophilic dye-treated animals. Fluorescence in contralateral eyes of liposomal-lipophilic dye-treated animals was significantly higher compared to non-liposomal-lipophilic dye-treated animals. CONCLUSIONS Topically applied liposomal formulation of lipophilic substance provides higher corneal concentration of drug with lesser systemic absorption compared to its solution. For hydrophilic substance, topical use of solution provides greater corneal concentration compared to liposomes which is more likely to be absorbed systemically.
Collapse
Affiliation(s)
- Nurul Alimah Abdul Nasir
- a Faculty of Medicine , Universiti Teknologi MARA, Sungai Buloh Campus , Sungai Buloh , Malaysia.,b Brain & Neuroscience, Communities of Research (Core), Research Management Institute (RMI), Universiti Teknologi MARA , Shah Alam , Malaysia
| | - Puneet Agarwal
- c Department of Ophthalmology , International Medical University, IMU Clinical School , Jalan Rasah , Seremban , Malaysia
| | - Renu Agarwal
- a Faculty of Medicine , Universiti Teknologi MARA, Sungai Buloh Campus , Sungai Buloh , Malaysia.,b Brain & Neuroscience, Communities of Research (Core), Research Management Institute (RMI), Universiti Teknologi MARA , Shah Alam , Malaysia
| | - Igor Iezhitsa
- a Faculty of Medicine , Universiti Teknologi MARA, Sungai Buloh Campus , Sungai Buloh , Malaysia.,b Brain & Neuroscience, Communities of Research (Core), Research Management Institute (RMI), Universiti Teknologi MARA , Shah Alam , Malaysia.,d Research Institute of Pharmacology, Volgograd State Medical University , Volgograd , Russia
| | - Renad Alyautdin
- a Faculty of Medicine , Universiti Teknologi MARA, Sungai Buloh Campus , Sungai Buloh , Malaysia.,b Brain & Neuroscience, Communities of Research (Core), Research Management Institute (RMI), Universiti Teknologi MARA , Shah Alam , Malaysia.,e Scientific Centre for Expertise of Medical Application Products, Ministry of Health , Moscow , Russia
| | - Natalia N Nukolova
- f Laboratory of Chemical Design of Bionanomaterials , Chemistry Department, M.V. Lomonosov Moscow State University , Moscow , Russia , and.,g Department of Fundamental and Applied Neurobiology , Serbsky National Research Center for Social and Forensic Psychiatry , Moscow , Russia
| | - Vladimir P Chekhonin
- g Department of Fundamental and Applied Neurobiology , Serbsky National Research Center for Social and Forensic Psychiatry , Moscow , Russia
| | - Nafeeza Mohd Ismail
- a Faculty of Medicine , Universiti Teknologi MARA, Sungai Buloh Campus , Sungai Buloh , Malaysia.,b Brain & Neuroscience, Communities of Research (Core), Research Management Institute (RMI), Universiti Teknologi MARA , Shah Alam , Malaysia
| |
Collapse
|
34
|
Takamura Y, Tomomatsu T, Matsumura T, Takihara Y, Kozai S, Arimura S, Yokota S, Inatani M. Vitreous and aqueous concentrations of brimonidine following topical application of brimonidine tartrate 0.1% ophthalmic solution in humans. J Ocul Pharmacol Ther 2015; 31:282-5. [PMID: 25918904 DOI: 10.1089/jop.2015.0003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
PURPOSE To determine the vitreous and aqueous concentrations of brimonidine after topical application of the ophthalmic solution 0.1%. METHODS The prospective observational case series included patients with an idiopathic epiretinal membrane or macular hole who were scheduled for a pars plana vitrectomy. Brimonidine tartrate ophthalmic solution 0.1% was topically administered twice daily for 1 week preoperatively. Vitreous and aqueous humor was collected before vitrectomy, and then, the brimonidine concentration was measured with liquid chromatography tandem spectrometry (LC/MS/MS). RESULTS Twenty-four patients (19 phakic eyes and 5 pseudophakic eyes) were enrolled. The mean concentrations in the aqueous humor and vitreous were 336.0 ± 276.2 and 4.8 ± 3.2 nM, respectively. A significant relationship was observed between the vitreous and aqueous samples (P = 0.034, R(2) = 0.22). Nineteen (79%) of the 24 eyes showed more than 2 nM of brimonidine tartrate concentration in the vitreous. In the phakic eyes, the mean concentration of brimonidine in the vitreous was 4.9 ± 3.3 nM, while the mean concentration in the pseudophakic eyes was 4.1 ± 2.4 nM, demonstrating no significant difference between pseudophakic and phakic eyes (P = 0.59). CONCLUSIONS After 1 week of dosing, in most of the patients who topically received brimonidine tartrate 0.1%, the concentration in the vitreous of the molecule was above 2 nM, which is known to activate neuroprotective α-2 receptors in animal retina. The drug penetration into the vitreous seems to be independent of lens status.
Collapse
Affiliation(s)
- Yoshihiro Takamura
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| | - Takeshi Tomomatsu
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| | - Takehiro Matsumura
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| | - Yuji Takihara
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| | | | - Shogo Arimura
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| | - Satoshi Yokota
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan.,3Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masaru Inatani
- 1Department of Ophthalmology, Faculty of Medical Sciences, University of Fukui, Fukui-ken, Japan
| |
Collapse
|
35
|
Sakaki H, Kakehi M, Sadamoto K, Nemoto S, Kurata M. In vitro comet assay in cultured human corneal epithelial cells. ACTA ACUST UNITED AC 2015. [DOI: 10.2131/fts.2.147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Hideyuki Sakaki
- Toxicological Research Laboratory, Senju Pharmaceutical Co., Ltd
| | - Masaki Kakehi
- Toxicological Research Laboratory, Senju Pharmaceutical Co., Ltd
| | - Kazuyo Sadamoto
- Toxicological Research Laboratory, Senju Pharmaceutical Co., Ltd
| | - Shingo Nemoto
- Toxicological Research Laboratory, Senju Pharmaceutical Co., Ltd
| | - Masaaki Kurata
- Toxicological Research Laboratory, Senju Pharmaceutical Co., Ltd
| |
Collapse
|
36
|
Kim YC, Edelhauser HF, Prausnitz MR. Targeted delivery of antiglaucoma drugs to the supraciliary space using microneedles. Invest Ophthalmol Vis Sci 2014; 55:7387-97. [PMID: 25212782 DOI: 10.1167/iovs.14-14651] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PURPOSE In this work, we tested the hypothesis that highly targeted delivery of antiglaucoma drugs to the supraciliary space by using a hollow microneedle allows dramatic dose sparing of the drug compared to topical eye drops. The supraciliary space is the most anterior portion of the suprachoroidal space, located below the sclera and above the choroid and ciliary body. METHODS A single, hollow 33-gauge microneedle, 700 to 800 μm in length, was inserted into the sclera and used to infuse antiglaucoma drugs into the supraciliary space of New Zealand white rabbits (N = 3-6 per group). Sulprostone, a prostaglandin analog, and brimonidine, an α₂-adrenergic agonist, were delivered via supraciliary and topical administration at various doses. The drugs were delivered unilaterally, and intraocular pressure (IOP) of both eyes was measured by rebound tonometry for 9 hours after injection to assess the pharmacodynamic responses. To assess safety of the supraciliary injection, IOP change immediately after intravitreal and supraciliary injection were compared. RESULTS Supraciliary delivery of both sulprostone and brimonidine reduced IOP by as much as 3 mm Hg bilaterally in a dose-related response; comparison with topical administration at the conventional human dose showed approximately 100-fold dose sparing by supraciliary injection for both drugs. A safety study showed that the kinetics of IOP elevation immediately after supraciliary and intravitreal injection of placebo formulations were similar. CONCLUSIONS This study introduced the use of targeted drug delivery to the supraciliary space by using a microneedle and demonstrated dramatic dose sparing of antiglaucoma therapeutic agents compared to topical eye drops. Targeted delivery in this way can increase safety by reducing side effects and could allow a single injection to contain enough drug for long-term sustained delivery.
Collapse
Affiliation(s)
- Yoo C Kim
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States
| | - Henry F Edelhauser
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States
| | - Mark R Prausnitz
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia, United States
| |
Collapse
|
37
|
Ho LC, Conner IP, Do CW, Kim SG, Wu EX, Wollstein G, Schuman JS, Chan KC. In vivo assessment of aqueous humor dynamics upon chronic ocular hypertension and hypotensive drug treatment using gadolinium-enhanced MRI. Invest Ophthalmol Vis Sci 2014; 55:3747-57. [PMID: 24764067 DOI: 10.1167/iovs.14-14263] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Although glaucoma treatments alter aqueous humor (AH) dynamics to lower intraocular pressure, the regulatory mechanisms of AH circulation and their contributions to the pathogenesis of ocular hypertension and glaucoma remain unclear. We hypothesized that gadolinium-enhanced magnetic resonance imaging (Gd-MRI) can visualize and assess AH dynamics upon sustained intraocular pressure elevation and pharmacologic interventions. METHODS Gadolinium contrast agent was systemically administered to adult rats to mimic soluble AH components entering the anterior chamber (AC) via blood-aqueous barrier. Dynamic Gd-MRI was applied to examine the signal enhancement in AC and vitreous body upon microbead-induced ocular hypertension and unilateral topical applications of latanoprost, timolol maleate, and brimonidine tartrate to healthy eyes. RESULTS Gadolinium signal time courses in microbead-induced hypertensive eyes possessed faster initial gadolinium uptake and higher peak signals in AC than control eyes, reflective of reduced gadolinium clearance upon microbead occlusion. Opposite trends were observed in latanoprost- and timolol-treated eyes, indicative of their respective drug actions on increased uveoscleral outflow and reduced AH production. The slowest initial gadolinium uptake but strongest peak signals were found in AC of both brimonidine-treated and untreated fellow eyes. These findings drew attention to the systemic effects of topical hypotensive drug treatment. Gadolinium leaked into the vitreous of microbead-induced hypertensive eyes and brimonidine-treated and untreated fellow eyes, suggestive of a compromise of aqueous-vitreous or blood-ocular barrier integrity. CONCLUSIONS Gadolinium-enhanced MRI allows spatiotemporal and quantitative evaluation of altered AH dynamics and ocular tissue permeability for better understanding the physiological mechanisms of ocular hypertension and the efficacy of antiglaucoma drug treatments.
Collapse
Affiliation(s)
- Leon C Ho
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Ian P Conner
- UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States Louis J. Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Chi-Wai Do
- School of Optometry, The Hong Kong Polytechnic University, Hung Hom, Hong Kong, China
| | - Seong-Gi Kim
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States Center for Neuroscience Imaging Research, Institute for Basic Science, Department of Biological Science, Sungkyunkwan University, Suwon, Korea Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, Pennsylvania, United States
| | - Ed X Wu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Gadi Wollstein
- UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States Louis J. Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Joel S Schuman
- UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States Louis J. Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Kevin C Chan
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, Pennsylvania, United States UPMC Eye Center, Eye and Ear Institute, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States Louis J. Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania, United States Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, Pennsylvania, United States
| |
Collapse
|
38
|
Kompella UB, Amrite AC, Pacha Ravi R, Durazo SA. Nanomedicines for back of the eye drug delivery, gene delivery, and imaging. Prog Retin Eye Res 2013; 36:172-98. [PMID: 23603534 DOI: 10.1016/j.preteyeres.2013.04.001] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 03/28/2013] [Accepted: 04/04/2013] [Indexed: 01/25/2023]
Abstract
Treatment and management of diseases of the posterior segment of the eye such as diabetic retinopathy, retinoblastoma, retinitis pigmentosa, and choroidal neovascularization is a challenging task due to the anatomy and physiology of ocular barriers. For instance, traditional routes of drug delivery for therapeutic treatment are hindered by poor intraocular penetration and/or rapid ocular elimination. One possible approach to improve ocular therapy is to employ nanotechnology. Nanomedicines, products of nanotechnology, having at least one dimension in the nanoscale include nanoparticles, micelles, nanotubes, and dendrimers, with and without targeting ligands. Nanomedicines are making a significant impact in the fields of ocular drug delivery, gene delivery, and imaging, the focus of this review. Key applications of nanotechnology discussed in this review include a) bioadhesive nanomedicines; b) functionalized nanomedicines that enhance target recognition and/or cell entry; c) nanomedicines capable of controlled release of the payload; d) nanomedicines capable of enhancing gene transfection and duration of transfection; f) nanomedicines responsive to stimuli including light, heat, ultrasound, electrical signals, pH, and oxidative stress; g) diversely sized and colored nanoparticles for imaging, and h) nanowires for retinal prostheses. Additionally, nanofabricated delivery systems including implants, films, microparticles, and nanoparticles are described. Although the above nanomedicines may be administered by various routes including topical, intravitreal, intravenous, transscleral, suprachoroidal, and subretinal routes, each nanomedicine should be tailored for the disease, drug, and site of administration. In addition to the nature of materials used in nanomedicine design, depending on the site of nanomedicine administration, clearance and toxicity are expected to differ.
Collapse
Affiliation(s)
- Uday B Kompella
- Nanomedicine and Drug Delivery Laboratory, Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
| | | | | | | |
Collapse
|
39
|
Deokule SP, Baffi JZ, Guo H, Nazzaro M, Kaneko H. Evaluation of extended release brimonidine intravitreal device in normotensive rabbit eyes. Acta Ophthalmol 2012; 90:e344-8. [PMID: 22676067 DOI: 10.1111/j.1755-3768.2012.02418.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE To evaluate the safety profile of a brimonidine extended release intravitreal implant, in normotensive rabbit eyes. METHODS Devices were made from hollow poly-l-lactic acid (PLA) tubes and contained hundred micrograms of brimonidine pamoate. Device was injected intravitreally in one eye of 12 New Zealand pigmented rabbits, whereas other eye was injected with a sham implant in masked fashion. Ocular examination was conducted at baseline and months 1, 3 and 6 including dilated fundus examination and electro-retinogram (ERG). Four rabbits were sacrificed at each time-point for retinal histology. ERG data were compared between groups and time-points using anova. RESULTS No complications were reported from either eye of any rabbits over a 6-month period. Photopic A wave was reduced in the control eye at 1 month compared with baseline (p < 0.01). There was no significant difference in other ERG parameters between the groups at different time-points. Gross retinal histology was normal at all time-points. CONCLUSION Extended release intravitreal brimonidine device was found to be safe and in normotensive rabbit eyes.
Collapse
Affiliation(s)
- Sunil P Deokule
- Department of Ophthalmology and Visual Sciences, University of Kentucky, Lexington, KY, USA.
| | | | | | | | | |
Collapse
|
40
|
Hosoya KI, Tomi M, Tachikawa M. Strategies for therapy of retinal diseases using systemic drug delivery: relevance of transporters at the blood-retinal barrier. Expert Opin Drug Deliv 2011; 8:1571-87. [PMID: 22035231 DOI: 10.1517/17425247.2011.628983] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION There is an increasing need for managing rapidly progressing retinal diseases because of the potential loss of vision. Although systemic drug administration is one possible route for treating retinal diseases, retinal transfer of therapeutic drugs from the circulating blood is strictly regulated by the blood-retinal barrier (BRB). AREAS COVERED This review discusses the constraints and challenges of drug delivery to the retina. In addition, this article discusses the properties of drugs and the conditions of the BRB that affect drug permeability. The reader will gain insights into the strategies for developing therapeutic drugs that are able to cross the BRB for treating retinal diseases. Further, the reader will gain insights into the role of BRB physiology including barrier functions, and the effect of influx and efflux transporters on retinal drug delivery. EXPERT OPINION When designing and selecting optimal drug candidates, it's important to consider the fact that they should be recognized by influx transporters and that efflux transporters at the BRB should be avoided. Although lipophilic cationic drugs are known to be transported to the brain across the blood-brain barrier, verapamil transport to the retina is substantially higher than to the brain. Therefore, lipophilic cationic drugs do have a great ability to increase influx transport across the BRB.
Collapse
Affiliation(s)
- Ken-ichi Hosoya
- University of Toyama, Graduate School of Medicine and Pharmaceutical Sciences, Department of Pharmaceutics, 2630, Sugitani, Toyama 930 0194, Japan.
| | | | | |
Collapse
|
41
|
Grueb M, Mielke J, Rohrbach JM, Schlote T. Effect of Brimonidine on Corneal Thickness. J Ocul Pharmacol Ther 2011; 27:503-9. [DOI: 10.1089/jop.2010.0198] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Matthias Grueb
- Department of Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Private Practice, Augenarztpraxis Breisach, Breisach am Rhein, Germany
| | | | | | - Torsten Schlote
- Department of Ophthalmology, University of Tuebingen, Tuebingen, Germany
- Day Clinic Ambimed, Basel, Switzerland
| |
Collapse
|
42
|
Abstract
Treatment in glaucoma aims to lower intraocular pressure (IOP) to reduce the risk of progression and vision loss. The alpha2-adrenergic receptor agonist brimonidine effectively lowers IOP and is useful as monotherapy, adjunctive therapy, and replacement therapy in open-angle glaucoma and ocular hypertension. A fixed combination of brimonidine and timolol, available in some countries, reduces IOP as effectively as concomitant therapy with brimonidine and timolol and offers the convenience of 2 drugs in a single eyedrop. Brimonidine is safe and well tolerated. Its most common side-effects are conjunctival hyperemia, allergic conjunctivitis, and ocular pruritus. The newest formulation of brimonidine, brimonidine-Purite 0.1%, has a higher pH to improve the ocular bioavailability of brimonidine. This formulation contains the lowest effective concentration of brimonidine and is preserved with Purite(R) to enhance ocular tolerability. Brimonidine-Purite 0.1% is as effective in reducing IOP as the original brimonidine 0.2% solution preserved with benzalkonium chloride. Recent results from preclinical and clinical studies suggest that brimonidine may protect retinal ganglion cells and their projections from damage and death independently of its effects on IOP. The potential for neuroprotection with brimonidine is an added benefit of its use in glaucoma and ocular hypertension.
Collapse
Affiliation(s)
- Louis B Cantor
- Department of Ophthalmology, Indiana University Indianapolis, IN, USA
| |
Collapse
|
43
|
Pinar-Sueiro S, Urcola H, Agurtzane Rivas M, Vecino E. Prevention of retinal ganglion cell swelling by systemic brimonidine in a rat experimental glaucoma model. Clin Exp Ophthalmol 2011; 39:799-807. [DOI: 10.1111/j.1442-9071.2011.02573.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
44
|
Arthur S, Cantor LB. Update on the role of alpha-agonists in glaucoma management. Exp Eye Res 2011; 93:271-83. [PMID: 21524649 DOI: 10.1016/j.exer.2011.04.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 04/03/2011] [Accepted: 04/04/2011] [Indexed: 11/19/2022]
Abstract
Glaucoma is the second most common cause of world blindness (following cataract) with estimated cases reaching 79.6 million by 2020. Although the etiology of glaucoma is multi-factorial, intraocular pressure (IOP) is the only modifiable factor in glaucoma management proven to alter the natural course of the disease. Among various classes of IOP-lowering medications currently available, alpha-adrenergic receptor agonists are used either as monotherapy, as second-line therapy, or in fixed combination with beta-blockers. Non-selective adrenergic agonists such as epinephrine and dipivefrin are infrequently used today for the treatment of glaucoma or ocular hypertension, and have been replaced by the alpha-2-selective agonists. The use of apraclonidine for IOP reduction in glaucoma or OHT is limited due to a high rate of follicular conjunctivitis. The alpha-2-selective agonist in use today is brimonidine. The brimonidine-purite formulations are preferred to brimonidine-benzalkonium chloride (BAC) formulations due better tolerability while maintaining similar efficacy. Brimonidine is also effective when used in combination with a beta-blocker. Using brimonidine-timolol fixed combination (BTFC) as first-line therapy has an added potential for neuroprotection. This would be a valuable strategy for glaucoma treatment, for patients who are intolerant of prostaglandin analogs, or for patients where prostaglandin analogues are contraindicated as first-line therapy, such as in patients with inflammatory glaucoma.
Collapse
Affiliation(s)
- Stella Arthur
- Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 702 Rotary Circle, Indianapolis, IN 46202, USA
| | | |
Collapse
|
45
|
Proksch JW, Ward KW. Ocular pharmacokinetics/pharmacodynamics of besifloxacin, moxifloxacin, and gatifloxacin following topical administration to pigmented rabbits. J Ocul Pharmacol Ther 2011; 26:449-58. [PMID: 20874668 DOI: 10.1089/jop.2010.0054] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The purpose of this investigation was to evaluate the ocular pharmacokinetic/pharmacodynamic (PK/PD) relationship for besifloxacin, moxifloxacin, and gatifloxacin using rabbit ocular PK data, along with in vitro minimum inhibitory concentration (MIC90) values against methicillin- and ciprofloxacin-resistant Staphylococcus aureus (MRSA-CR) and Staphylococcus epidermidis (MRSE-CR). METHODS Rabbits received a topical instillation of Besivance™ (besifloxacin ophthalmic suspension, 0.6%), Vigamox (moxifloxacin hydrochloride ophthalmic solution, 0.5% as base), or Zymar (gatifloxacin ophthalmic solution, 0.3%), and ocular tissues and plasma were collected from 4 animals/treatment/collection time at 8 predetermined time intervals during the 24h after dosing. Ocular levels of each agent were measured by LC/MS/MS, and PK parameters (Cmax, Tmax, and AUC₀₋₂₄) were determined. AUC₀₋₂₄/MIC₉₀ ratios were calculated for tears, conjunctiva, cornea, and aqueous humor using previously reported MIC₉₀values for MRSA-CR and MRSE-CR. RESULTS All of the fluoroquinolones tested demonstrated rapid penetration into ocular tissues after a single instillation. Besifloxacin demonstrated the highest exposure in tear fluid, while exposure in conjunctiva was comparable for all 3 compounds. Peak concentrations of all fluoroquinolones in aqueous humor were at or below ~1g/mL. In comparison with their MIC₉₀values against MRSE-CR and MRSA-CR, besifloxacin achieved an AUC₀₋₂₄/MIC₉₀ ratio of ~800 in tears, compared with values of ≤10 for moxifloxacin and gatifloxacin. In cornea, conjunctiva, and aqueous humor, the AUC₀₋₂₄/MIC₉₀ ratios were <10 for all compounds. However, in these tissues AUC₀₋₂₄/MIC₉₀ ratios for besifloxacin were 1.5- to 38-fold higher than moxifloxacin and gatifloxacin. CONCLUSIONS In rabbits, besifloxacin demonstrates a nonclinical ocular PK profile characterized by high and sustained concentrations in tear fluid, resulting in AUC₀₋₂₄/MIC₉₀ ratios of ~800 for ciprofloxacin-resistant MRSE and MRSA after a single administration. Although besifloxacin had the highest AUC₀₋₂₄/MIC₉₀ratios for intraocular tissues, the ratios for all of the drugs were below the target values needed for effective bacterial killing of ciprofloxacin-resistant MRSE and MRSA. Taken together, these nonclinical data indicate that besifloxacin has a favorable ocular PK/PD profile, consistent with the reported clinical efficacy of besifloxacin in the treatment of bacterial conjunctivitis, and consistent with the profile needed for ocular surface sterilization.
Collapse
Affiliation(s)
- Joel W Proksch
- Global Pharmaceutical Research & Development , Bausch & Lomb, Incorporated, Rochester, NY 14609, USA.
| | | |
Collapse
|
46
|
Lambert WS, Ruiz L, Crish SD, Wheeler LA, Calkins DJ. Brimonidine prevents axonal and somatic degeneration of retinal ganglion cell neurons. Mol Neurodegener 2011; 6:4. [PMID: 21232114 PMCID: PMC3035592 DOI: 10.1186/1750-1326-6-4] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Accepted: 01/13/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Brimonidine is a common drug for lowering ocular pressure and may directly protect retinal ganglion cells in glaucoma. The disease involves early loss of retinal ganglion cell transport to brain targets followed by axonal and somatic degeneration. We examined whether brimonidine preserves ganglion cell axonal transport and abates degeneration in rats with elevated ocular pressure induced by laser cauterization of the episcleral veins. RESULTS Ocular pressure was elevated unilaterally by 90% for a period of 8 weeks post- cauterization. During this time, brimonidine (1mg/kg/day) or vehicle (phosphate-buffered saline) was delivered systemically and continuously via subcutaneous pump. Animals received bilateral intravitreal injections of fluorescent cholera toxin subunit β (CTB) two days before sacrifice to assess anterograde transport. In retinas from the vehicle group, elevated pressure induced a 44% decrease in the fraction of ganglion cells with intact uptake of CTB and a 14-42% reduction in the number of immuno-labelled ganglion cell bodies, with the worst loss occurring nasally. Elevated pressure also caused a 33% loss of ganglion cell axons in vehicle optic nerves and a 70% decrease in CTB transport to the superior colliculus. Each of these components of ganglion cell degeneration was either prevented or significantly reduced in the brimonidine treatment group. CONCLUSIONS Continuous and systemic treatment with brimonidine by subcutaneous injection significantly improved retinal ganglion cell survival with exposure to elevated ocular pressure. This effect was most striking in the nasal region of the retina. Brimonidine treatment also preserved ganglion cell axon morphology, sampling density and total number in the optic nerve with elevated pressure. Consistent with improved outcome in the optic projection, brimonidine also significantly reduced the deficits in axonal transport to the superior colliculus associated with elevated ocular pressure. As transport deficits to and from retinal ganglion cell projection targets in the brain are relevant to the progression of glaucoma, the ability of brimonidine to preserve optic nerve axons and active transport suggests its neuroprotective effects are relevant not only at the cell body, but throughout the entire optic projection.
Collapse
Affiliation(s)
- Wendi S Lambert
- The Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN 37205, USA.
| | | | | | | | | |
Collapse
|
47
|
Gadek T, Lee D. Topical Drug Delivery to the Back of the Eye. DRUG PRODUCT DEVELOPMENT FOR THE BACK OF THE EYE 2011. [DOI: 10.1007/978-1-4419-9920-7_5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
48
|
Amrite A, Pugazhenthi V, Cheruvu N, Kompella U. Delivery of celecoxib for treating diseases of the eye: influence of pigment and diabetes. Expert Opin Drug Deliv 2010; 7:631-45. [PMID: 20205602 DOI: 10.1517/17425241003663236] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Age-related macular degeneration (AMD) and diabetic retinopathy (DR) are two major causes of blindness. In these disorders, growth factors such as vascular endothelial growth factor (VEGF) are upregulated, leading to either enhanced vascular permeability or proliferation of endothelium. While corticosteroid therapies available at present suffer from side effects including cataracts and elevated intraocular pressure, anti-VEGF antibody therapies require frequent intravitreal injections, a procedure that can potentially lead to retinal detachment or endophthalmitis. Thus, there is a need to develop safe, sustained release therapeutic approaches for treating AMD and DR. AREAS COVERED IN THIS REVIEW This review discusses the pharmacological basis for using celecoxib, an anti-inflammatory drug capable of selectively inhibiting cycloxygenase 2, in treating AMD and DR. In addition, this article discusses the safety, delivery advantage and efficacy of celecoxib by transscleral retinal delivery, a periocular delivery approach that is less invasive to the globe compared with intravitreal injections. WHAT THE READER WILL GAIN The reader will gain insights into the development of a pharmacological agent and a sustained release delivery system for treating DR and AMD. Further, the reader will gain insights into the influence of eye physiology including pigmentation and disease states such as DR on retinal drug delivery. TAKE HOME MESSAGE Transscleral sustained delivery of anti-inflammatory agents is a viable option for treating retinal disorders.
Collapse
Affiliation(s)
- Aniruddha Amrite
- Quinitles, Inc., Clinical Pharmacology, Overland Park, KS 66211, USA
| | | | | | | |
Collapse
|
49
|
Park JH, Kim SJ, Yu HG. The effect of brimonidine on transepithelial resistance in a human retinal pigment epithelial cell line. KOREAN JOURNAL OF OPHTHALMOLOGY 2010; 24:169-72. [PMID: 20532144 PMCID: PMC2882081 DOI: 10.3341/kjo.2010.24.3.169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 05/07/2010] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To investigate the effects of brimonidine, an alpha-2-adrenergic agonist, on barrier function in ARPE-19 cells by measuring transepithelial resistance (TER). METHODS ARPE-19 cells were cultured into a confluent monolayer on a microporous filter. Brimonidine was added to the apical medium, and the barrier function of the cells was evaluated by measuring TER. A subset of cells was treated under hypoxic conditions, and the TER changes observed upon administration of brimonidine were compared to those observed in cells in normoxic conditions. RESULTS The ARPE cell membrane reached a peak resistance of 29.1+/-7.97 Omegacm(2) after four weeks of culture. The TER of the cells treated under normoxic conditions increased with brimonidine treatment; however, the TER of the cells treated under hypoxic conditions did not change following the administration of brimonidine. CONCLUSIONS Barrier function in ARPE-19 cells increased with brimonidine treatment. Understanding the exact mechanism of this barrier function change requires further investigation.
Collapse
Affiliation(s)
- Jung Hyun Park
- Department of Ophthalmology, Seoul Paik Hospital, Inje University College of Medicine, Seoul, Korea
| | | | | |
Collapse
|
50
|
Tomi M, Hosoya KI. The role of blood–ocular barrier transporters in retinal drug disposition: an overview. Expert Opin Drug Metab Toxicol 2010; 6:1111-24. [DOI: 10.1517/17425255.2010.486401] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|