1
|
Topical dexamethasone delivery to the retina: An aqueous cyclodextrin-based microsuspension. J Drug Deliv Sci Technol 2023. [DOI: 10.1016/j.jddst.2023.104281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
|
2
|
Physicochemical and Stability Evaluation of Topical Niosomal Encapsulating Fosinopril/γ-Cyclodextrin Complex for Ocular Delivery. Pharmaceutics 2022; 14:pharmaceutics14061147. [PMID: 35745720 PMCID: PMC9228017 DOI: 10.3390/pharmaceutics14061147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 05/25/2022] [Accepted: 05/26/2022] [Indexed: 11/17/2022] Open
Abstract
This study aimed to develop a chemically stable niosomal eye drop containing fosinopril (FOS) for lowering intraocular pressure. The effects of cyclodextrin (CD), surfactant types and membrane stabilizer/charged inducers on physiochemical and chemical properties of niosome were evaluated. The pH value, average particle size, size distribution and zeta potentials were within the acceptable range. All niosomal formulations were shown to be slightly hypertonic with low viscosity. Span® 60/dicetyl phosphate niosomes in the presence and absence of γCD were selected as the optimum formulations according to their high %entrapment efficiency and negative zeta potential values as well as controlled release profile. According to ex vivo permeation study, the obtained lowest flux and apparent permeability coefficient values confirmed that FOS/γCD complex was encapsulated within the inner aqueous core of niosome and could be able to protect FOS from its hydrolytic degradation. The in vitro cytotoxicity revealed that niosome entrapped FOS or FOS/γCD formulations were moderate irritation to the eyes. Furthermore, FOS-loaded niosomal preparations exhibited good physical and chemical stabilities especially of those in the presence of γCD, for at least three months under the storage condition of 2–8 °C.
Collapse
|
3
|
Loftsson T, Stefánsson E. Aqueous eye drops containing drug/cyclodextrin nanoparticles deliver therapeutic drug concentrations to both anterior and posterior segment. Acta Ophthalmol 2022; 100:7-25. [PMID: 33876553 DOI: 10.1111/aos.14861] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 02/27/2021] [Accepted: 03/02/2021] [Indexed: 12/12/2022]
Abstract
Using topical application to deliver therapeutic concentrations of drugs to the posterior segment of the eye remains very challenging. As a result, posterior segment diseases are usually treated by intravitreal injection or implant. While topical treatments are commonly used for anterior segment conditions, they sometimes require frequent applications. Eye drop formulations based on γ-cyclodextrin (γCD)-based nanoparticle aggregates were developed, which in animal models and clinical studies deliver therapeutic concentrations of drugs (dorzolamide and dexamethasone) to both anterior and posterior segments of the eye. An early study in humans showed dorzolamide/γCD eye drops could achieve comparable intraocular pressure decreases to commercial dorzolamide eye drops, but with less frequent application. Pilot studies with dexamethasone/γCD eye drops suggested that they could be effective in a range of conditions, including diabetic macular oedema, cystoid macular oedema and vitritis secondary to uveitis, postcataract surgery inflammation and postoperative treatment in trabeculectomy. Phase II studies with similar dexamethasone/γCD nanoparticle eye drops in diabetic macular oedema and postcataract surgery inflammation have recently been completed. This technology has the potential to be used with other classes of drug molecules and to replace or complement invasive treatments, providing safer, non-invasive therapies, particularly for posterior segment conditions, that can be self-administered as eye drops by patients.
Collapse
|
4
|
Hnin HM, Stefánsson E, Loftsson T, Rungrotmongkol T, Jansook P. Angiotensin converting enzyme inhibitors/cyclodextrin inclusion complexes: solution and solid-state characterizations and their thermal stability. J INCL PHENOM MACRO 2022. [DOI: 10.1007/s10847-021-01124-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
5
|
Jansook P, Hnin HM, Loftsson T, Stefánsson E. Cyclodextrin-based formulation of carbonic anhydrase inhibitors for ocular delivery - A review. Int J Pharm 2021; 606:120955. [PMID: 34332063 DOI: 10.1016/j.ijpharm.2021.120955] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/15/2021] [Accepted: 07/26/2021] [Indexed: 10/20/2022]
Abstract
Carbonic anhydrase inhibitors (CAIs) are used as systemic and topical agents for lowering intraocular pressure (IOP) in patients with glaucoma. Owing to the wide distribution of CAs and their physiological functions in various tissues, systemic administration of CAIs may lead to unwanted side effects. Thus, exploration of drugs targeting the specific CA isoenzyme in ocular tissues and application of the same as topical eye drops would be desirable. However, the anatomical and physiological barriers of the eyes can limit drug availability at the site. The very low aqueous solubility of CAI agents can further hamper drug bioavailability, consequently resulting in insufficient therapeutic efficacy. Solubilization of drugs using cyclodextrin (CD) complexes can enhance both solubility and permeability of the drugs. The use of CD for such purposes and development and testing of topical CAI eye drops containing CD have been discussed in detail. Further, pharmaceutical nanotechnology platforms were discussed in terms of investigation of their IOP-lowering efficacies. Future prospects in drug discovery and the use of CD nanoparticles and CD-based nanocarriers to develop potential topical CAI formulations have also been described here.
Collapse
Affiliation(s)
- Phatsawee Jansook
- Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phyathai Road, Pathumwan, Bangkok 10330, Thailand.
| | - Hay Marn Hnin
- Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phyathai Road, Pathumwan, Bangkok 10330, Thailand
| | - Thorsteinn Loftsson
- Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, IS-107 Reykjavik, Iceland
| | - Einar Stefánsson
- Department of Ophthalmology, Faculty of Medicine, National University Hospital, University of Iceland, Landspitalinn, IS-101 Reykjavik, Iceland
| |
Collapse
|
6
|
Roy Chowdhury U, Kudgus RA, Holman BH, Rinkoski TA, Hann CR, Bahler CK, McCloud E, Appt SE, Reid JM, Dosa PI, Fautsch MP. Pharmacological Profile and Ocular Hypotensive Effects of Cromakalim Prodrug 1, a Novel ATP-Sensitive Potassium Channel Opener, in Normotensive Dogs and Nonhuman Primates. J Ocul Pharmacol Ther 2021; 37:251-260. [PMID: 33784195 PMCID: PMC8215408 DOI: 10.1089/jop.2020.0137] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 02/27/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: To evaluate pharmacokinetic parameters and ocular hypotensive effects of cromakalim prodrug 1 (CKLP1) in normotensive large animal models. Methods: Optimal CKLP1 concentration was determined by dose response and utilized in short- (5-8 days) and long-term (60 days) evaluation in hound dogs (n = 5) and African Green Monkeys (n = 5). Blood pressure was recorded 3-5 times per week with a tail cuff. Concentrations of CKLP1 and the parent compound levcromakalim were assessed in hound dog plasma and select tissues by LC-MS/MS after bilateral ocular treatment with CKLP1 for 8 days. Pharmacokinetic parameters were calculated from days 1, 4, and 8 data. After necropsy, histology was assessed in 43 tissue samples from each animal. Results: In hound dogs and African Green monkeys, 10 mM CKLP1 (optimal concentration) significantly lowered intraocular pressure (IOP) by 18.9% ± 1.1% and 16.7% ± 6.7%, respectively, compared with control eyes (P < 0.05). During treatment, no significant change in systolic or diastolic blood pressure was observed in either species (P > 0.1). Average values for half-life of CKLP1 was 295.3 ± 140.4 min, Cmax, 10.5 ± 1.6 ng/mL, and area under the concentration vs. time curve (AUClast) 5261.4 ± 918.9 ng·min/mL. For levcromakalim, average values of half-life were 96.2 ± 27 min, Cmax 1.2 ± 0.2 ng/mL, and AUClast 281.2 ± 110.8 ng·min/mL. No significant pathology was identified. Conclusions: CKLP1 lowered IOP in hound dogs and African green monkeys with no effect on systemic blood pressure. Ocular topical treatment of CKLP1 showed excellent tolerability even after extended treatment periods.
Collapse
Affiliation(s)
- Uttio Roy Chowdhury
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Rachel A. Kudgus
- Department of Oncology Research, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Bradley H. Holman
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Tommy A. Rinkoski
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Cheryl R. Hann
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Cindy K. Bahler
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Eric McCloud
- Department of Pathology, Section of Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Susan E. Appt
- Department of Pathology, Section of Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Joel M. Reid
- Department of Oncology Research, Mayo Clinic Rochester, Rochester, Minnesota, USA
| | - Peter I. Dosa
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota, USA
| | - Michael P. Fautsch
- Department of Ophthalmology, Mayo Clinic Rochester, Rochester, Minnesota, USA
| |
Collapse
|
7
|
Wang R, Gao Y, Liu A, Zhai G. A review of nanocarrier-mediated drug delivery systems for posterior segment eye disease: challenges analysis and recent advances. J Drug Target 2021; 29:687-702. [PMID: 33474998 DOI: 10.1080/1061186x.2021.1878366] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Posterior segment eye disease is a leading cause of irreversible vision impairment and blindness. As the unique organ for vision, eyes are protected by various protective barriers. The existence of physiological barriers and elimination mechanisms makes it challenging to treat the posterior segment eye diseases. To achieve efficient drug delivery to the posterior segment of eyes, different drug delivery systems have been proposed. Due to their abilities to enhance ocular tissue permeability, make controlled drug release and target retina, nanocarriers, such as lipid nanoparticles, liposomes and polymeric nanomicelles, have been widely studied for posterior segment drug delivery. However, clinical applications of nanocarrier mediated drug delivery systems as non-invasive ocular drops is still not ready. The delivery of nanocarrier-mediated drug for posterior segment disease still faces the choice of being more effective or more invasive for long-term treatment. Therefore, it is necessary to have a clear understanding of the barriers and the routes of ocular drug delivery while developing the delivery systems. In this review, types of ocular barriers and drug administration routes are categorised in a more intuitive way. Recent advances in nanocarrier mediated drug delivery systems with focus on posterior segment are reviewed with illustrative examples.
Collapse
Affiliation(s)
- Rui Wang
- School of Pharmaceutical Sciences, Key Laboratory of Chemical Biology, Ministry of Education, Shandong University, Jinan, China
| | - Yuan Gao
- School of Pharmaceutical Sciences, Key Laboratory of Chemical Biology, Ministry of Education, Shandong University, Jinan, China
| | - Anchang Liu
- Department of Pharmacy, Qilu Hospital of Shandong University, Jinan, China
| | - Guangxi Zhai
- School of Pharmaceutical Sciences, Key Laboratory of Chemical Biology, Ministry of Education, Shandong University, Jinan, China
| |
Collapse
|
8
|
Roy Chowdhury U, Kudgus RA, Rinkoski TA, Holman BH, Bahler CK, Hann CR, Reid JM, Dosa PI, Fautsch MP. Pharmacological and pharmacokinetic profile of the novel ocular hypotensive prodrug CKLP1 in Dutch-belted pigmented rabbits. PLoS One 2020; 15:e0231841. [PMID: 32298376 PMCID: PMC7162492 DOI: 10.1371/journal.pone.0231841] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 04/01/2020] [Indexed: 11/19/2022] Open
Abstract
Elevated intraocular pressure is the only treatable risk factor for glaucoma, an eye disease that is the leading cause of irreversible blindness worldwide. We have identified cromakalim prodrug 1 (CKLP1), a novel water-soluble ATP-sensitive potassium channel opener, as a new ocular hypotensive agent. To evaluate the pharmacokinetic and safety profile of CKLP1 and its parent compound levcromakalim, Dutch-belted pigmented rabbits were treated intravenously (0.25 mg/kg) or topically (10 mM; 4.1 mg/ml) with CKLP1. Body fluids (blood, aqueous and vitreous humor) were collected at multiple time points and evaluated for the presence of CKLP1 and levcromakalim using a liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) based assay. Histology of tissues isolated from Dutch-belted pigmented rabbits treated once daily for 90 days was evaluated in a masked manner by a certified veterinary pathologist. The estimated plasma parameters following intravenous administration of 0.25 mg/kg of CKLP1 showed CKLP1 had a terminal half-life of 61.8 ± 55.2 min, Tmax of 19.8 ± 23.0 min and Cmax of 1968.5 ± 831.0 ng/ml. Levcromakalim had a plasma terminal half-life of 85.0 ± 37.0 min, Tmax of 61.0 ± 32.0 min and Cmax of 10.6 ± 1.2 ng/ml. Topical CKLP1 treatment in the eye showed low levels (<0.3 ng/mL) of levcromakalim in aqueous and vitreous humor, and trace amounts of CKLP1 and levcromakalim in the plasma. No observable histological changes were noted in selected tissues that were examined following topical application of CKLP1 for 90 consecutive days. These results suggest that CKPL1 is converted to levcromakalim in the eye and likely to some extent in the systemic circulation.
Collapse
Affiliation(s)
- Uttio Roy Chowdhury
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| | - Rachel A. Kudgus
- Department of Oncology Research, Mayo Clinic, Rochester, MN, United States of America
| | - Tommy A. Rinkoski
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| | - Bradley H. Holman
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| | - Cindy K. Bahler
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| | - Cheryl R. Hann
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| | - Joel M. Reid
- Department of Oncology Research, Mayo Clinic, Rochester, MN, United States of America
| | - Peter I. Dosa
- Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, MN, United States of America
| | - Michael P. Fautsch
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, United States of America
| |
Collapse
|
9
|
De Matteis V, Rizzello L. Noble Metals and Soft Bio-Inspired Nanoparticles in Retinal Diseases Treatment: A Perspective. Cells 2020; 9:E679. [PMID: 32164376 PMCID: PMC7140625 DOI: 10.3390/cells9030679] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/06/2020] [Accepted: 03/08/2020] [Indexed: 02/06/2023] Open
Abstract
We are witnessing an exponential increase in the use of different nanomaterials in a plethora of biomedical fields. We are all aware of how nanoparticles (NPs) have influenced and revolutionized the way we supply drugs or how to use them as therapeutic agents thanks to their tunable physico-chemical properties. However, there is still a niche of applications where NP have not yet been widely explored. This is the field of ocular delivery and NP-based therapy, which characterizes the topic of the current review. In particular, many efforts are being made to develop nanosystems capable of reaching deeper sections of the eye such as the retina. Particular attention will be given here to noble metal (gold and silver), and to polymeric nanoparticles, systems consisting of lipid bilayers such as liposomes or vesicles based on nonionic surfactant. We will report here the most relevant literature on the use of different types of NPs for an efficient delivery of drugs and bio-macromolecules to the eyes or as active therapeutic tools.
Collapse
Affiliation(s)
- Valeria De Matteis
- Department of Mathematics and Physics “Ennio De Giorgi”, University of Salento, Via Arnesano, 73100 Lecce, Italy
| | - Loris Rizzello
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK;
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, 08028 Barcelona, Spain
- Department of Pharmaceutical Sciences, University of Milan, via Mangiagalli 25, 20133 Milano, Italy
| |
Collapse
|
10
|
Himawan E, Ekström P, Buzgo M, Gaillard P, Stefánsson E, Marigo V, Loftsson T, Paquet-Durand F. Drug delivery to retinal photoreceptors. Drug Discov Today 2019; 24:1637-1643. [PMID: 30877076 PMCID: PMC6715772 DOI: 10.1016/j.drudis.2019.03.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 01/21/2019] [Accepted: 03/05/2019] [Indexed: 12/14/2022]
Abstract
Routes of administration to retinal photoreceptors. The blood–retinal barrier as a challenge for photoreceptor drug delivery. Review of nanoparticle drug delivery systems used for intraocular applications. Perspectives for topical drug delivery to the retina.
The photoreceptors of the retina are afflicted by diseases that still often lack satisfactory treatment options. Although suitable drugs might be available in some cases, the delivery of these compounds into the eye and across the blood–retinal barrier remains a significant challenge for therapy development. Here, we review the routes of drug administration to the retina and highlight different options for drug delivery to the photoreceptor cells.
Collapse
Affiliation(s)
| | - Per Ekström
- Lund University, Faculty of Medicine, Department of Clinical Sciences Lund, Ophthalmology, Lund, Sweden
| | | | | | | | - Valeria Marigo
- Department of Life Sciences, University of Modena and Reggio Emilia, Italy
| | - Thorsteinn Loftsson
- Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavík, Iceland
| | | |
Collapse
|
11
|
Topical drug delivery to the posterior segment of the eye: The effect of benzalkonium chloride on topical dexamethasone penetration into the eye in vivo. J Drug Deliv Sci Technol 2018. [DOI: 10.1016/j.jddst.2018.09.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
12
|
Ocular Drug Delivery Barriers-Role of Nanocarriers in the Treatment of Anterior Segment Ocular Diseases. Pharmaceutics 2018; 10:pharmaceutics10010028. [PMID: 29495528 PMCID: PMC5874841 DOI: 10.3390/pharmaceutics10010028] [Citation(s) in RCA: 198] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/12/2018] [Accepted: 02/23/2018] [Indexed: 12/20/2022] Open
Abstract
Ocular drug delivery is challenging due to the presence of anatomical and physiological barriers. These barriers can affect drug entry into the eye following multiple routes of administration (e.g., topical, systemic, and injectable). Topical administration in the form of eye drops is preferred for treating anterior segment diseases, as it is convenient and provides local delivery of drugs. Major concerns with topical delivery include poor drug absorption and low bioavailability. To improve the bioavailability of topically administered drugs, novel drug delivery systems are being investigated. Nanocarrier delivery systems demonstrate enhanced drug permeation and prolonged drug release. This review provides an overview of ocular barriers to anterior segment delivery, along with ways to overcome these barriers using nanocarrier systems. The disposition of nanocarriers following topical administration, their safety, toxicity and clinical trials involving nanocarrier systems are also discussed.
Collapse
|
13
|
Loftsson T, Stefánsson E. Cyclodextrins and topical drug delivery to the anterior and posterior segments of the eye. Int J Pharm 2017; 531:413-423. [PMID: 28391041 DOI: 10.1016/j.ijpharm.2017.04.010] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/04/2017] [Accepted: 04/05/2017] [Indexed: 12/31/2022]
Abstract
It is generally believed that it is virtually impossible to obtain therapeutic drug concentrations in the posterior segment of the eye after topical application of aqueous, low viscosity eye drops. Thus, intravitreal drug injections and drug implants are currently used to treat diseases in the posterior segment such as macular edema. Here it is described how, through proper analysis of the drug permeation barriers and application of well-known pharmaceutical excipients, aqueous eye drops are designed that can deliver lipophilic drugs to the posterior segment as well as how such eye drops can maintain high drug concentrations in the anterior segment. Through stepwise optimization, eye drops containing solid drug/cyclodextrin complex microparticles with a mean diameter of 2-4μm, dissolved drug/cyclodextrin complex nanoparticles and dissolved drug molecules in an aqueous eye drop media of low viscosity were designed. After administration of the eye drops the microparticles slowly dissolved and maintained close to saturated drug concentrations in the aqueous tear fluid for several hours. Studies in rabbits and clinical evaluations in humans, using dorzolamide and dexamethasone as sample drugs, show that the eye drops deliver significant amounts of drugs to both the posterior segment and anterior segment of the eye. Clinical studies indicate that the eye drops can replace intravitreal injections and implants that are currently used to treat ophthalmic diseases and decrease frequency of drug administration, both of which can improve patient compliance.
Collapse
Affiliation(s)
- Thorsteinn Loftsson
- Faculty of Pharmaceutical Sciences, University of Iceland, Hofsvallagata 53, IS-107 Reykjavik, Iceland.
| | - Einar Stefánsson
- Department of Ophthalmology, Faculty of Medicine, National University Hospital, Eiríksgata 37, IS-101 Reykjavík, Iceland
| |
Collapse
|
14
|
Anticancer and radio-sensitizing evaluation of some new sulfonamide derivatives bearing pyridone, thiophene, and hydrazone moieties. RESEARCH ON CHEMICAL INTERMEDIATES 2017. [DOI: 10.1007/s11164-017-2903-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
15
|
Vullo D, Supuran CT, Scozzafava A, De Simone G, Monti SM, Alterio V, Carta F. Kinetic and X-ray crystallographic investigations of substituted 2-thio-6-oxo-1,6-dihydropyrimidine–benzenesulfonamides acting as carbonic anhydrase inhibitors. Bioorg Med Chem 2016; 24:3643-8. [DOI: 10.1016/j.bmc.2016.06.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/31/2016] [Accepted: 06/02/2016] [Indexed: 01/14/2023]
|
16
|
Vullo D, Durante M, Di Leva FS, Cosconati S, Masini E, Scozzafava A, Novellino E, Supuran CT, Carta F. Monothiocarbamates Strongly Inhibit Carbonic Anhydrases in Vitro and Possess Intraocular Pressure Lowering Activity in an Animal Model of Glaucoma. J Med Chem 2016; 59:5857-67. [PMID: 27253845 DOI: 10.1021/acs.jmedchem.6b00462] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
A series of monothiocarbamates (MTCs) were prepared from primary/secondary amines and COS as potential carbonic anhydrase (CA, EC 4.2.1.1) inhibitors, using the dithiocarbamates, the xanthates, and the trithiocarbonates as lead compounds. The MTCs effectively inhibited the pharmacologically relevant human (h) hCAs isoforms I, II, IX, and XII in vitro and showed KIs spanning between the low and medium nanomolar range. By means of a computational study, the MTC moiety binding mode on the CAs was explained. Furthermore, a selection of MTCs were evaluated in a normotensive glaucoma rabbit model for their intraocular pressure (IOP) lowering effects and showed interesting activity.
Collapse
Affiliation(s)
- Daniela Vullo
- Polo Scientifico, Laboratorio di Chimica Bioinorganica, Università degli Studi di Firenze , Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy
| | - Mariaconcetta Durante
- Dipartimento NEUROFARBA, Sezione di Farmacologia, Università degli Studi di Firenze , Viale Pieraccini 6, 50139 Florence, Italy
| | - Francesco Saverio Di Leva
- Department of Pharmacy, University of Naples "Federico II" , Via D. Montesano 49, 80131 Naples, Italy
| | - Sandro Cosconati
- DiSTABiF, Seconda Università di Napoli , Via Vivaldi 43, 81100 Caserta, Italy
| | - Emanuela Masini
- Dipartimento NEUROFARBA, Sezione di Farmacologia, Università degli Studi di Firenze , Viale Pieraccini 6, 50139 Florence, Italy
| | - Andrea Scozzafava
- Polo Scientifico, Laboratorio di Chimica Bioinorganica, Università degli Studi di Firenze , Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy
| | - Ettore Novellino
- Department of Pharmacy, University of Naples "Federico II" , Via D. Montesano 49, 80131 Naples, Italy
| | - Claudiu T Supuran
- Polo Scientifico, Laboratorio di Chimica Bioinorganica, Università degli Studi di Firenze , Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.,Dipartimento NEUROFARBA, Sezione di Scienze Farmaceutiche, Università degli Studi di Firenze , Via Ugo Schiff 6, 50019 Sesto Fiorentino, Florence, Italy
| | - Fabrizio Carta
- Polo Scientifico, Laboratorio di Chimica Bioinorganica, Università degli Studi di Firenze , Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy
| |
Collapse
|
17
|
Jansook P, Muankaew C, Stefánsson E, Loftsson T. Development of eye drops containing antihypertensive drugs: formulation of aqueous irbesartan/γCD eye drops. Pharm Dev Technol 2014; 20:626-32. [PMID: 24754413 DOI: 10.3109/10837450.2014.910811] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Aqueous nanoparticulated eye drop formulations based on γ-cyclodextrin (γCD) complexes were developed and tested in vitro. Three antihypertensive drugs, i.e. enalapril maleate, irbesartan and verapamil HCl, that have been shown to possess IOP-lowering activity were selected for this study. All three drugs displayed Bs-type phase-solubility diagrams in aqueous γCD solutions and had relatively low affinity for γCD. Irbesartan was selected for further formulation development. The drug was relatively stable at pH 4.5 but somewhat less stable at physiologic pH. However, presence of γCD in the aqueous media enhanced the chemical stability of irbesartan. Aqueous γCD-based eye drop formulations containing 1% and 2% (w/v) irbesartan were prepared and the effect of pH on the particles size distribution and drug release investigated. Only ∼2% of the drug was in solution in the pH 4.5 formulations but up to 45% in the pH 7 formulations. The pH 7 formulations, where larger fraction of the drug was in solution, displayed somewhat greater drug permeation flux but much lower drug permeation coefficients than the pH 4.5 formulations. Dynamic light scattering studies indicated the faster permeation was due to formation of smaller particles in presence tyloxapol.
Collapse
Affiliation(s)
- Phatsawee Jansook
- Faculty of Pharmaceutical Sciences, Chulalongkorn University , Bangkok , Thailand
| | | | | | | |
Collapse
|
18
|
Syamaiah K, Mallikarjuna Reddy G, Padmavathi V, Padmaja A. Synthesis and antimicrobial activity of some new amido/sulfonamido-linked 3,4-disubstituted pyrroles. Med Chem Res 2014. [DOI: 10.1007/s00044-014-0908-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
19
|
|
20
|
Del Solar V, Quiñones-Lombraña A, Cabrera S, Padrón JM, Ríos-Luci C, Alvarez-Valdés A, Navarro-Ranninger C, Alemán J. Expanding the synthesis of new trans-sulfonamide platinum complexes: cytotoxicity, SAR, fluorescent cell assays and stability studies. J Inorg Biochem 2013; 127:128-40. [PMID: 23474039 DOI: 10.1016/j.jinorgbio.2013.01.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/19/2013] [Accepted: 01/21/2013] [Indexed: 01/12/2023]
Abstract
In this manuscript, we describe the synthesis of new trans-N-sulfonamide platinum complexes and their antiproliferative activity (GI50, μM) in human solid tumors cells. The structure activity relationships (SAR), with different new synthesized complexes by variation in ligand, halogen and also in the stereochemistry of the ligand, has been studied. Solubility and stability studies have also been carried out as well as fluorescent cell assays in order to clarify the final target in the tumor cells.
Collapse
Affiliation(s)
- Virginia Del Solar
- Departamento de Química Inorgánica (Módulo 7), Facultad de Ciencias, Universidad Autónoma de Madrid, 28049, Madrid, Spain
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Malagola R, Arrico L, Giannotti R, Pattavina L. Acetazolamide-induced cilio-choroidal effusion after cataract surgery: unusual posterior involvement. Drug Des Devel Ther 2013; 7:33-6. [PMID: 23378740 PMCID: PMC3556858 DOI: 10.2147/dddt.s38324] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Idiosyncratic reactions to a large number of drugs have been reported to cause choroidal detachment and secondary angle-closure glaucoma (ACG). We report a case of bilateral acute ACG and peculiar choroidal effusion following administration of oral acetazolamide immediately after cataract surgery. Few cases of acute secondary ACG with choroidal effusion and anterior shift of the lens-iris diaphragm have been associated with acetazolamide compared with other sulfonamides. As far as we are aware, posterior involvement with retinal folds and papillary edema due to acetazolamide has not been described before.
Collapse
Affiliation(s)
- Romualdo Malagola
- Department of Ophthalmology, University of Rome La Sapienza, Rome, Italy
| | | | | | | |
Collapse
|
22
|
Abstract
Topically applied carbonic anhydrase inhibitors (CAIs) in eye drop solutions are commonly used to treat glaucoma. However, local eye irritation and multiple daily administrations may hamper their clinical usefulness. Aqueous eye drop formulations that improve their topical bioavailability and reduce their eye irritation can improve their clinical efficacy. Earlier studies showed that dorzolamide and closely related CAIs are more effectively delivered into the eye from acidic eye drop solutions than from comparable neutral solutions. Consequently, dorzolamide was marketed as an aqueous pH 5.6 eye drop solution (Trusopt(®) , Merck). Later, it was shown that increasing the pH of the eye drops from pH 5.6 to physiologic pH significantly reduced their local irritation. Earlier attempts to use cyclodextrins (CDs) as ocular penetration enhancers in dorzolamide eye drop solutions failed since; although the CDs were able to enhance the aqueous solubility of dorzolamide, increasing the pH from 5.6 to physiologic pH reduced the ability of the drug to permeate into the eye. Later, it was discovered that formulating the drug as aqueous dorzolamide/γCD eye drop microparticle suspension resulted in significant bioavailability enhancement. The solid dorzolamide/γCD microparticles are mucoadhesive and release dorzolamide into the aqueous tear fluid for extended time period. Consequently, sustained high dorzolamide concentrations in aqueous humour and various eye tissues were observed after single administration of the aqueous dorzolamide/γCD eye drop microsuspension. The microsuspension has a potential of being developed into a once-a-day eye drop product. This article reviews the physicochemical properties of dorzolamide, its permeation characteristics and topical bioavailability.
Collapse
Affiliation(s)
- Thorsteinn Loftsson
- Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland.
| | | | | |
Collapse
|
23
|
Carta F, Scozzafava A, Supuran CT. Sulfonamides: a patent review (2008 – 2012). Expert Opin Ther Pat 2012; 22:747-58. [DOI: 10.1517/13543776.2012.698264] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
24
|
Carta F, Aggarwal M, Maresca A, Scozzafava A, McKenna R, Masini E, Supuran CT. Dithiocarbamates strongly inhibit carbonic anhydrases and show antiglaucoma action in vivo. J Med Chem 2012; 55:1721-30. [PMID: 22276570 DOI: 10.1021/jm300031j] [Citation(s) in RCA: 192] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A series of dithiocarbamates were prepared by reaction of primary/secondary amines with carbon disulfide in the presence of bases. These compounds were tested for the inhibition of four human (h) isoforms of the zinc enzyme carbonic anhydrase, CA (EC 4.2.1.1), hCA I, II, IX, and XII, involved in pathologies such as glaucoma (CA II and XII) or cancer (CA IX). Several low nanomolar inhibitors targeting these CAs were detected. The X-ray crystal structure of the hCA II adduct with morpholine dithiocarbamate evidenced the inhibition mechanism of these compounds, which coordinate to the metal ion through a sulfur atom from the dithiocarbamate zinc-binding function. Some dithiocarbamates showed an effective intraocular pressure lowering activity in an animal model of glucoma.
Collapse
Affiliation(s)
- Fabrizio Carta
- Laboratorio di Chimica Bioinorganica, Polo Scientifico, Università degli Studi di Firenze, Room 188, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy
| | | | | | | | | | | | | |
Collapse
|
25
|
Abstract
Muscarinic agonists act mainly via muscarinic M₃ cholinoceptors to cause contraction of the iris sphincter, ciliary muscle and trabecular meshwork as well as increase outflow facility of aqueous humour. In the iris dilator, the effect of muscarinic agonists is species dependent but is predominantly relaxation via muscarinic M₃ receptors. In the conjunctiva, muscarinic agonists stimulate goblet cell secretion which contributes to the protective tear film. Muscarinic M₂ and M₃ receptors appear mainly involved. In the lens muscarinic agonists act via muscarinic M₁ receptors to produce depolarization and increase [Ca(2+)](i). All five subtypes of muscarinic receptor are present in the retina. In the developing retina, acetylcholine appears to limit purinergic stimulation of retinal development and decrease cell proliferation. In the adult retina acetylcholine and other muscarinic agonists may have complex effects, for example, enhancing light-evoked neuronal firing in transient ON retinal ganglion cells and inhibiting firing in OFF retinal ganglion cells. In the lacrimal gland, muscarinic agonists activate M₃ receptors on secretory globular acinar cells to stimulate tear secretion and also cause contraction of myoepithelial cells. In Sjögren's syndrome, antibodies to the muscarinic M₃ receptor disrupt normal gland function leading to xerophthalmia although the mechanism of action of the antibody is still not clear. Atropine and pirenzepine are useful in limiting the development of myopia in children probably by an action on muscarinic receptors in the sclera, although many other muscarinic receptor antagonists are not effective.
Collapse
Affiliation(s)
- Frederick Mitchelson
- Department of Pharmacology, University of Melbourne, Melbourne, VIC 3010, Australia.
| |
Collapse
|
26
|
Alemán J, del Solar V, Alvarez-Valdés A, Ríos-Luci C, Padrón JM, Navarro-Ranninger C. Novel N-sulfonamide trans-platinum complexes: synthesis, reactivity and in vitro evaluation. MEDCHEMCOMM 2011. [DOI: 10.1039/c1md00070e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
27
|
Benedetti MS, Whomsley R, Poggesi I, Cawello W, Mathy FX, Delporte ML, Papeleu P, Watelet JB. Drug metabolism and pharmacokinetics. Drug Metab Rev 2009; 41:344-90. [PMID: 19601718 DOI: 10.1080/10837450902891295] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In this article, aspects of absorption, distribution, metabolism, and excretion have been described bearing in mind the pathogenesis of allergic diseases and their possible therapeutic opportunities. The importance of the routes of administration of the different therapeutic groups has been emphasized. The classical aspects of drug metabolism and disposition related to oral administration have been reviewed, but special emphasis has been given to intranasal, cutaneous, transdermal, and ocular administration as well as to the absorption and the subsequent bioavailability of drugs. Drug-metabolizing enzymes and transporters present in extrahepatic tissues, such as nasal mucosa and the respiratory tract, have been particularly discussed. As marketed antiallergic drugs include both racemates and enantiomers, aspects of stereoselective absorption, distribution, metabolism, and excretion have been discussed. Finally, a new and promising methodology, microdosing, has been presented, although it has not yet been applied to drugs used in the treatment of allergic diseases.
Collapse
|
28
|
Supuran CT, Scozzafava A. Carbonic anhydrase inhibitors and their therapeutic potential. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.10.5.575] [Citation(s) in RCA: 426] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
29
|
Lux A, Dinslage S, Süverkrüp R, Maier S, Diestelhorst M. Comparaison de deux formes d’application de médicaments : collyre versus lyophilisat. J Fr Ophtalmol 2005; 28:185-9. [PMID: 15851952 DOI: 10.1016/s0181-5512(05)81041-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE The ocular bioavailability of a single application of a triple dose of sodium fluorescein to the human anterior segment of the eye was studied as a novel drug delivery device. METHODS The lyophilisate contained a fluorescein dose of 204 microg corresponding to three conventional, preservative-free eye drops of 40 microl Fluorescein SE Thilo 0.17% (68microg each) (Alcon). A single lyophilisate was applied to one eye of 22 healthy volunteers (+1 min) and three conventional eye drops (+1, 16, 31 min) were applied to their fellow eye. In this randomized, open label study, fluorophotometry was performed (Fluorotron Master IItrade mark, Ocumetrics, Mountain View, California, USA) before and +15, 30, 45, 60, 120, 180, 240, 300, 360, 420 min after application. The fluorescein concentrations of the corneal stroma (C), mid-anterior chamber (AC) were analyzed by paired t-test. RESULTS Cornea and AC mean values (ng/ml) were significantly higher (p < 0.018, paired t-test) in the lyophilisate group up to 7 h after application, with the exception of +45 min. The mean fluorescein bioavailability from the lyophilisate was up to 11 times higher in the C and up to 8.7 times higher in the AC compared with the three preservative-free eye drops. DISCUSSION For the first time a triple dose was delivered to the human eye with a single lyophilisate application. Significantly better bioavailability was achieved in the C and AC for up to 7 h using this new device. The treatment of glaucoma, bacterial, viral, and fungal infections, as well as dry eye syndrome, for example, will be improved using lyophilisate.
Collapse
Affiliation(s)
- A Lux
- Département d'Ophtalmologie, Université de Cologne, Allemagne
| | | | | | | | | |
Collapse
|
30
|
Remko M, von der Lieth CW. Theoretical study of gas-phase acidity, pKa, lipophilicity, and solubility of some biologically active sulfonamides. Bioorg Med Chem 2004; 12:5395-403. [PMID: 15388166 DOI: 10.1016/j.bmc.2004.07.049] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2004] [Accepted: 07/23/2004] [Indexed: 11/22/2022]
Abstract
The geometries of 19 biologically active substituted sulfonamides (including clinically useful acetazolamide, methazolamide, ethoxzolamide, dichlorophenamide, dorzolamide, and brinzolamide) in both neutral and deprotonated forms, were optimized using Becke3LYP/6-311+G(d,p) method (compounds 1-6) and two-layered ONIOM (B3LYP 6-311+G(d,p): MNDO) method (compounds 7-19). The investigated sulfonamides are weak acids with calculated acidity of about 1320-1420 kJ mol(-1). Of acids studied the highest gas-phase acidity (1324 kJ mol(-1)) possesses methazolamide. This drug is, according to the computed pKa value (5.9), also in water solution the most acidic compound of the sulfonamides investigated. The computed pKa values varied between 5.9 and 12.6 and correlate well with the available experimental pKa's found in the literature. Cancerostatic aromatic sulfonamides 16-19 are generally weak acids with the acidity comparable or slightly lower than the lead sulfanilamide. The available experimental partition coefficients of sulfonamides investigated are best reproduced by the IA LOGP method. Computed partition coefficients for antiglaucoma sulfonamides 1-13 varied between -0.47 and 2.61 (IA LOGP). Thus these compounds are only slightly or moderate lipophilic. The lipophilicity of the cancerostatic sulfonamides 14-18 is from relatively narrow interval between -0.07 and 1.68 (IA LOGP). The most potent CAI 10-13 are also the most lipophilic compounds among the antiglaucomatics studied. The available experimental solubilities are best reproduced by the IA LOGS method. The computed solubilities qualitatively correlate with the corresponding lipophilicities, logS increasing as logP declines. The analysis of molecular descriptors defined by Lipinski have been shown that all of the sulfonamides studied obey 'Rule of 5'. Therefore, in the early stages of the design of antiglaucoma sulfonamides, it is becoming more important to determine the pKa, lipophilicity, water solubility, and other physicochemical properties associated with a drug, before synthetic work is undertaken, with the aim of avoiding the synthesis of compounds that are predicted to have poor biopharmaceutical characteristics.
Collapse
Affiliation(s)
- Milan Remko
- Department of Pharmaceutical Chemistry, Comenius University, Odbojarov 10, SK-832 32 Bratislava, Slovakia.
| | | |
Collapse
|
31
|
Steinfeld A, Lux A, Maier S, Süverkrüp R, Diestelhorst M. Bioavailability of fluorescein from a new drug delivery system in human eyes. Br J Ophthalmol 2004; 88:48-53. [PMID: 14693772 PMCID: PMC1771947 DOI: 10.1136/bjo.88.1.48] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2003] [Indexed: 11/03/2022]
Abstract
AIM To assess the ocular bioavailability of fluorescein from a novel drug delivery system compared with one single preservative free eye drop. METHODS Part A: In a randomised study 10 volunteers applied the lyophilisate to one eye and a conventional fluorescein eye drop to the fellow eye. Fluorophotometry was performed before and every 2 minutes up to 30 minutes after application in the cornea and anterior chamber. Part B: Another 10 volunteers applied each form of the application. Fluorophotometry was performed before, +2 minutes, and at +8, +10, +12 hours. The dose corresponding to a single fluorescein dose of the lyophilisate was 68 l microg fluorescein SE 0.17%. RESULTS Part A: During the first 30 minutes after administration of the preservative free eye drop of 40 microg the corneal and anterior chamber concentration means were up to 16 times higher in eyes treated with the lyophilisate. Part B: 8-12 hours after application the mean fluorescein concentration in the cornea of the lyophilisate group was two times higher than at baseline. Eyes treated with eye drops had baseline values at +8, +10 and +12 hours. CONCLUSION A significantly better bioavailability was achieved in human eyes by using lyophilisate compared with the same dose from a conventional eye drop. Lyophilisates are a favourable alternative to conventional eye drops since they have no preservatives, higher long term stability, no pH adjustment, and easy handling.
Collapse
Affiliation(s)
- A Steinfeld
- Department of Ophthalmology, University of Cologne, Germany.
| | | | | | | | | |
Collapse
|
32
|
Lux A, Maier S, Dinslage S, Süverkrüp R, Diestelhorst M. A comparative bioavailability study of three conventional eye drops versus a single lyophilisate. Br J Ophthalmol 2003; 87:436-40. [PMID: 12642306 PMCID: PMC1771614 DOI: 10.1136/bjo.87.4.436] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2002] [Indexed: 11/04/2022]
Abstract
AIM To study the ocular bioavailability of a triple dose, single application of sodium fluorescein to the human anterior segment from a novel drug delivery device. METHODS In a randomised, open label study 22 healthy volunteers applied a single lyophilisate to one eye (+1 minute) and three conventional eye drops (+1, 16, 31 minutes) of fluorescein ophthalmic solution to the fellow eye. The fluorescein dose of the lyophilisate was 204 mg corresponding to three conventional, preservative-free eye drops of 40 ml fluorescein SE Thilo 0.17% (68 micro g each) (Alcon). Fluorophotometry was performed (Fluorotron Master II Ocumetrics, USA) before and +15, 30, 45, 60, 120, 180, 240, 300, 360, 420 minutes after application. The fluorescein concentrations of the corneal stroma and mid-anterior chamber were analysed by paired t test. RESULTS Cornea and anterior chamber mean values (ng/ml) were significantly higher (p<0.018, paired t test) in the lyophilisate group up to 7 hours after application with the exception of +45 minutes. The mean fluorescein bioavailability from the lyophilisate was up to 11 times higher in the cornea and up to 8.7 times higher in the anterior chamber compared with the three preservative-free eye drops. CONCLUSION A triple dose was delivered to the human eye with a single lyophilisate application for the first time. A significantly better bioavailability was achieved in the cornea and anterior chamber for up to 7 hours by means of drug application with lyophilisates. The application of medications by means of the lyophilisate will improve the treatment of, for example, glaucoma, bacterial, viral and fungal infections, as well as dry eye syndrome.
Collapse
Affiliation(s)
- A Lux
- Department of Ophthalmology, University of Cologne, Germany
| | | | | | | | | |
Collapse
|
33
|
Schwartz M. Neuroprotection as a treatment for glaucoma: pharmacological and immunological approaches. Eur J Ophthalmol 2003; 13 Suppl 3:S27-31. [PMID: 12749674 DOI: 10.1177/112067210301303s05] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Primary open-angle glaucoma is a chronic, progressive optic neuropathy associated with a gradual decline in visual function, which may lead to blindness. In most cases, the optic neuropathy is associated with increased intraocular pressure. It is now generally accepted, however, that normalization of pressure, although necessary, is often not-sufficient as a remedial measure. This is because of the existence of additional factors, some of which emerge as a consequence of the initial damage. This situation is reminiscent of the response to a traumatic axonal insult, in which some of the damage is immediate and is caused by the insult itself, and some is secondary and is caused by a deficiency of growth-supportive factors as well as by toxic factors derived from the damaged tissue. Accordingly, the author has suggested that glaucoma may be viewed as a neurodegenerative disease and consequently amenable to any therapeutic intervention applicable to neurodegenerative diseases. There is evidence that neuroprotection can be achieved both pharmacologically and immunologically. Pharmacologic intervention neutralizes some of the effects of the nerve-derived toxic factors and possibly increases the ability of the remaining healthy neurons, at any given time, to cope with the stressful conditions. Immunologic intervention boosts the body's repair mechanisms for counteracting the toxicity of physiologic compounds acting as stress signals.
Collapse
Affiliation(s)
- M Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
34
|
Remko M. Theoretical Study of Molecular Structure and Gas-Phase Acidity of Some Biologically Active Sulfonamides. J Phys Chem A 2003. [DOI: 10.1021/jp026980m] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Milan Remko
- Department of Pharmaceutical Chemistry, Comenius University, Odbojarov 10, SK-832 32 Bratislava, Slovakia
| |
Collapse
|
35
|
Maestrelli F, Mura P, Casini A, Mincione F, Scozzafava A, Supuran CT. Cyclodextrin complexes of sulfonamide carbonic anhydrase inhibitors as long-lasting topically acting antiglaucoma agents. J Pharm Sci 2002; 91:2211-9. [PMID: 12226848 DOI: 10.1002/jps.10215] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Complexes of several 1,3,4-thiadiazole-2-sulfonamide derivatives possessing strong carbonic anhydrase (CA) inhibitory properties with beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin were obtained and characterized. Although the investigated CA inhibitors possessed very powerful inhibitory properties against the two CA isozymes involved in aqueous humor production within the eye, i.e., CA II and CA IV, these compounds were topically ineffective as intraocular pressure (IOP) lowering agents in normotensive/hypertensive rabbits, due to their very low water solubility. On the contrary, the cyclodextrin-sulfonamide complexes proved to be effective and long-lasting IOP lowering agents in the two animal models of glaucoma mentioned above.
Collapse
Affiliation(s)
- Francesca Maestrelli
- Università degli Studi di Firenze, Dipartimento di Scienze Farmaceutiche, Via Gino Capponi 9, I-50121, Florence, Italy
| | | | | | | | | | | |
Collapse
|
36
|
Puras G, Santafé J, Segarra J, Garrido M, Melena J. Effects of topical natural ergot alkaloids on intraocular pressure and aqueous humor dynamics in ocular normotensive rabbits. J Ocul Pharmacol Ther 2002; 18:41-52. [PMID: 11858614 DOI: 10.1089/108076802317233207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Although it has been suggested that ergot derivatives may play a role in antiglaucoma therapy, little attention has been paid to the ocular hypotensive action of these drugs. Having previously reported in our laboratory that topical dihydroergocristine decreases intraocular pressure both in ocular normotensive and alpha-chymotrypsin-induced ocular hypertensive rabbits, the aim of the present work was to assess the effect of natural ergot alkaloids, ergocristine, alpha-ergocryptine and ergocornine, on the intraocular pressure and aqueous humor dynamics in ocular normotensive rabbits in order to further explore the ocular actions of these compounds. Intraocular pressure was measured with a pneumatonometer manometrically calibrated for the rabbit eye. Changes in tonographic facility of aqueous humor outflow and rate of aqueous humor inflow were evaluated in anesthetized rabbits. Natural ergot alkaloids were found to reduce intraocular pressure in ocular normotensive eyes in a dose-related fashion. These compounds decreased both tonographic outflow facility and, to a greater extent, aqueous humor inflow, which explains their final hypotensive effect.
Collapse
Affiliation(s)
- Gustavo Puras
- Department of Pharmacology, Faculty of Pharmacy, Basque Country University, Vitoria, Spain
| | | | | | | | | |
Collapse
|
37
|
Schwartz M. Neuroprotection as a treatment for glaucoma: pharmacological and immunological approaches. Eur J Ophthalmol 2001; 11 Suppl 2:S7-11. [PMID: 11592535 DOI: 10.1177/112067210101102s01] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE Primary open-angle glaucoma is a chronic, progressive optic neuropathy associated with a gradual decline in visual functions, which may lead to blindness. METHODS In most cases, the optic neuropathy is associated with increased intraocular pressure. However, it is now generally accepted, that normalization of pressure, although necessary, is often not sufficient as a remedial measure. This is because of the existence of additional risk factors, some of which emerge as a consequence of the initial damage. This situation is reminiscent of the response to a traumatic axonal insult: some of the damage is immediate and is caused by the insult itself, while some is secondary and is caused by a deficiency of growth-supportive factors as well as by toxic factors derived from the damaged tissue. Accordingly, we have suggested that glaucoma may be viewed as a neurodegenerative disease and consequently is amenable to any therapeutic intervention applicable to these diseases. CONCLUSIONS There is evidence that neuroprotection can be achieved both pharmacologically and immunologically. Pharmacological intervention (e.g. by using selective alpha-2 adrenergic receptor agonists) neutralizes some of the effects of the nerve-derived toxic factors and possibly increases the ability of the remaining healthy neurons, at any given time, to cope with the stressful conditions. Immunological intervention boosts the body's own repair mechanisms for counteracting the toxicity of physiological compounds acting as stress signals.
Collapse
Affiliation(s)
- M Schwartz
- Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
38
|
Cavallotti C, Pescosolido N, Leali FM, Gherardi F, Cavallotti D. Occurrence of cholinergic nerve fibers in the human uveoscleral tissue. Int Ophthalmol 2000; 22:349-53. [PMID: 10937850 DOI: 10.1023/a:1006306812296] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have studied the cholinergic nerve fibers (CNF) of human uveoscleral tissue in normal and pathological conditions (intraocular pressure: (IOP) of various degrees ) and have performed a quantitative image analysis of CNF with the aim of studying an hypothetical association between IOP and the uveoscleral level of cholinergic neurotransmitter in nerve fiber of the enucleated human eyes. Eleven patients, previously enrolled in our medical protocols are affected by an increase of IOP of various degrees, were subjected to surgical enucleation of one eyeball for traumatic or neoplastic reasons and were the donors of samples of the uveoscleral tissue for CNF demonstration. The samples were also submitted to quantitative image analysis. An enzymatic activity, Acetylcholinesterase (AChe), is present in nerve fibers that innervate the human uveoscleral tissue. The AChe-positive nerve fibers represent about 7.2% of the observed area in normal conditions, while in patients with elevated IOP AChe activity is about 20.3% of the total observed area. The increase of AChe activity in our experiments, all performed under the same conditions, and therefore, with comparable results, may be related with the increase of IOP.
Collapse
Affiliation(s)
- C Cavallotti
- Department of Cardiovascular and Respiratory Sciences, University La Sapienza, Rome, Italy.
| | | | | | | | | |
Collapse
|
39
|
Abstract
It is now commonly accepted that glaucoma is a neurodegenerative disease of the optic nerve. Thus, at any given time, there are neurons that, though still viable, are vulnerable to the hostile extracellular milieu and are therefore amenable to neuroprotective therapy. Neuroprotection refers to any intervention, either external to the optic nerve or internally, that will lead to an intracellular change in the balance between survival and death signals in favor of survival. Several potential sites and modalities for such intervention may exist. When designing neuroprotective therapy, ways must be sought to recruit the physiologic self-repair mechanisms awakened by the primary or secondary risk factors. These mechanisms appear to be insufficiently effective when in their natural state, but they may be simulated or boosted by appropriate therapeutic compounds or cells.
Collapse
Affiliation(s)
- M Schwartz
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | | |
Collapse
|
40
|
Mincione G, Menabuoni L, Briganti F, Mincione F, Scozzafava A, Supuran CT. Carbonic anhydrase inhibitors. Part 79. Synthesis of topically acting sulfonamides incorporating GABA moieties in their molecule, with long-lasting intraocular pressure-lowering properties. Eur J Pharm Sci 1999; 9:185-99. [PMID: 10620731 DOI: 10.1016/s0928-0987(99)00052-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Reaction of 26 aromatic/heterocyclic sulfonamides containing amino, imino, hydrazino or hydroxyl groups with N-tert-butoxycarbonyl-gamma-aminobutyric acid (Boc-GABA; Boc=t-butoxycarbonyl) in the presence of carbodiimide derivatives, afforded after removal of the protecting group, a series of water-soluble compounds (as salts of strong acids, such as hydrochloric, trifluoroacetic or trifluoromethane sulfonic). The new derivatives were assayed as inhibitors of the zinc enzyme carbonic anhydrase (CA), and more precisely of three of its isozymes, CA I, II (cytosolic forms) and IV (membrane-bound form), involved in important physiological processes. Some of the new compounds effectively inhibited CA II and CA IV (in the nanomolar range), the two isozymes known to play a critical role in aqueous humor secretion within the ciliary processes of the eye. Some of the best inhibitors obtained as described above were applied as 2% water solutions into the eye of normotensive or glaucomatous albino rabbits, when strong and long-lasting intraocular pressure (IOP) lowering has been evidenced. Thus, the amino acyl tail conferring water solubility to these sulfonamides, coupled with their strong enzyme inhibitory properties and balanced lipid solubility seem to be the key factors for obtaining compounds with effective topical antiglaucoma activity from the class of the carbonic anhydrase inhibitors.
Collapse
Affiliation(s)
- G Mincione
- Laboratorio di Chimica Inorganica e Bioinorganica, Università degli Studi, Via Gino Capponi 7, I-50121, Florence, Italy
| | | | | | | | | | | |
Collapse
|
41
|
Osborne NN, DeSantis L, Bae JH, Ugarte M, Wood JP, Nash MS, Chidlow G. Topically applied betaxolol attenuates NMDA-induced toxicity to ganglion cells and the effects of ischaemia to the retina. Exp Eye Res 1999; 69:331-42. [PMID: 10471341 DOI: 10.1006/exer.1999.0706] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present results show that topically applied Betoptic(R)(0.5% betaxolol) to the rabbit or rat eye reaches the retina and can counteract the detrimental effects caused by ischaemia/reperfusion or N -methyl- d -aspartate (NMDA)-induced insults to the retina. Betaxolol is a beta(1)-adrenergic blocker but its neuroprotective action is generally thought to be due to its calcium channel blocking properties. Support for this view comes from studies on cultures of cortical neurones where it was found that betaxolol attenuated the NMDA-induced influx of(45)Ca(2+)while beta-adrenoreceptor agonists were ineffective. Topically applied Betoptic(R)to the rabbit eye was observed to reach the retina in maximal amounts within 60 min. Some of the substance was also found in the contralateral retina of the untreated eye suggesting that the agent reaches the retina by local systemic and retinal circulation. Concurrent treatment with Latanoprost(R)did not result in a greater amount of betaxolol reaching the retina. An ophthalmodynamometric procedure, which raises the intraocular pressure, was used to apply an ischaemic insult to the rabbit retina. After three days of reperfusion the b-wave of the electroretinogram was reduced by an average of 59% and the choline acetyltransferase immunoreactivity in the retina was almost obliterated. However, when experiments were carried out on animals which had been treated with one drop of Betoptic(R) twice daily for 4 weeks before ischaemia and also during the reperfusion phase, the reductions in both the b-wave of the electroretinogram and retinal choline acetyltransferase immunoreactivity due to ischaemia/reperfusion were greatly attenuated. Intravitreal injection of NMDA into the rat eye caused a decrease in the immunostaining for Thy-1 antigen which is associated with ganglion cells. The Thy-1 mRNA level was also reduced as was the mRNA for the common subunit of the NMDA receptor, the NR1 subunit. However, in animals subjected to a topical Betoptic(R)regime, before and after intravitreal injection of NMDA, the decreases in the mRNA levels of Thy-1 and NR1 were significantly attenuated.
Collapse
Affiliation(s)
- N N Osborne
- Nuffield Laboratory of Ophthalmology, University of Oxford, Walton Street, Oxford, OX2 6AW, U.K
| | | | | | | | | | | | | |
Collapse
|
42
|
Buckley NE, Hansson S, Harta G, Mezey E. Expression of the CB1 and CB2 receptor messenger RNAs during embryonic development in the rat. Neuroscience 1998; 82:1131-49. [PMID: 9466436 DOI: 10.1016/s0306-4522(97)00348-5] [Citation(s) in RCA: 181] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We mapped the distribution of CB1 and CB2 receptor messenger RNAs in the developing rat to gain insight into how cannabinoids may affect embryogenesis. In situ hybridization histochemistry studies were done using riboprobes specific for CB1 or CB2 receptor messenger RNAs. We found that CB1 and CB2 receptor messenger RNAs are expressed in the placental cone and in the smooth muscle of the maternal uterus at the earliest gestational periods studied [from eight days of gestation (E8) through E12]. In the embryo, as early as E11, CB1 receptor messenger RNA is expressed in some cells of the neural tube and, at later embryological stages (from E15 to E21), in several distinct structures within the central nervous system. In addition, high levels of CB1 receptor messenger RNA were also found in areas of the peripheral nervous system such as the sympathetic and parasympathetic ganglia, in the retina and in the enteric ganglia of the gastrointestinal tract. In addition to neural structures, high levels of the CB1 receptor messenger RNA were also present in two endocrine organs, the thyroid gland and the adrenal gland. On the other hand, CB2 receptor messenger RNA is expressed exclusively in the liver of the embryo as early as E13. The region-specific expression of CB1 and CB2 receptor messenger RNAs suggests that these receptors have a functional role during embryogenesis.
Collapse
Affiliation(s)
- N E Buckley
- National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | | | | | | |
Collapse
|
43
|
Affiliation(s)
- M F Sugrue
- Merck Research Laboratories, West Point, Pennsylvania 19486, USA.
| |
Collapse
|
44
|
Balfour JA, Wilde MI. Dorzolamide. A review of its pharmacology and therapeutic potential in the management of glaucoma and ocular hypertension. Drugs Aging 1997; 10:384-403. [PMID: 9143858 DOI: 10.2165/00002512-199710050-00006] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Dorzolamide (dorzolamide hydrochloride), the first topical carbonic anhydrase (CA) inhibitor to become available for clinical use, lowers intraocular pressure (IOP) by reducing aqueous humour formation. It is formulated as a 2% eyedrop for use in the management of glaucoma and ocular hypertension. When administered 3 times daily, dorzolamide is effective in lowering IOP in patients with open-angle glaucoma or ocular hypertension. Mean IOP was reduced by approximately 4 to 6 mm Hg at peak (2 hours postdose) and 3 to 4.5 mm Hg at trough (8 hours postdose) in clinical trails. A 1-year comparative study showed that the ocular hypotensive efficacy of dorzolamine 2% 3 times daily was similar to that of betaxolol 0.5% twice daily, but slightly inferior to that of timolol 0.5% twice daily. Dorzolamide has additive ocular hypotensive effects when used in conjunction with topical beta-adrenergic antagonists and was as effective as pilocarpine 2% 4 times daily as adjunctive therapy in patients receiving timolol. Dorzolamide does not appear to produce the acid-base or electrolyte disturbances and severe systemic adverse events associated with oral CA inhibitors, and unlike beta-adrenergic antagonists, it is not contraindicated in patients with asthma, reactive airways disease or heart disease. Furthermore, as CA inhibitors do not cause miosis, they may cause less interference with vision than pilocarpine or epinephrine (adrenaline). The most common adverse effects associated with dorzolamide are bitter taste and transient local burning or stinging. Conjunctivitis was the most common reason for discontinuation of dorzolamide in one large study. Thus, available data suggest that dorzolamide has potential as an alternative therapy option in patients with glaucoma or ocular hypertension who are intolerant of, or unable to receive, ophthalmic beta-adrenergic antagonists and as adjunctive therapy in patients already receiving these agents. Further efficacy and tolerability data are needed to determine the place of dorzolamide in therapy.
Collapse
Affiliation(s)
- J A Balfour
- Adis International Limited, Auckland, New Zealand.
| | | |
Collapse
|
45
|
Schütte M, Wolosin JM. Ca2+ mobilization and interlayer signal transfer in the heterocellular bilayered epithelium of the rabbit ciliary body. J Physiol 1996; 496 ( Pt 1):25-37. [PMID: 8910193 PMCID: PMC1160821 DOI: 10.1113/jphysiol.1996.sp021662] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
1. 'Ratiometric' fura-2 methodology in slice preparations and 'intensitometric' fluo-3 measurements of confocal images were used to simultaneously monitor Ca2+ mobilization in the two distinct, apically joined cell layers which constitute the ciliary body epithelium (CBE): the non-pigmented (NPE) and pigmented (PE) epithelia. 2. Both methods yielded comparable results regarding Ca2+ responses in the syncytium upon stimulation with adrenergic and cholinergic agonists. 3. The alpha 1-adrenoceptor agonist phenylephrine elicited a moderate [Ca2+]i increase in the PE, whereas NPE [Ca2+]i remained unchanged or exhibited a slight diminution. 4. In combination with carbachol, the alpha 2-adrenoceptor agonist brimonidine elicited large Ca2+ increases (> 10-fold) in both the NPE and PE cell layers, even though previous studies indicated the absence of an alpha 2-adrenergic effect on [Ca2+]i in the PE. The onset, as well as the peak of the Ca2+ responses in PE cells frequently exhibited a small delay with respect to adjacent NPE cells. No such time difference was observed between adjacent NPE cells. 5. Pre-incubation of the ciliary body in Ca(2+)-free solution under conditions known to elicit overt NPE-PE separation abolished the alpha 2-adrenocholinergic response in the PE. 6. Addition of heptanol to the perfusate, to block gap-junctional communication, caused a small [Ca2+]i decrease in the NPE and a slight increase in PE[Ca2+]i. Subsequently, the Ca2+ mobilization in the Pe in response to the brimonidine and carbachol combination was either blocked or showed a substantial delay. The Ca2+ mobilization in the NPE, in contrast, remained unchanged. 7. We conclude that the heterocellular syncytium exhibits rectificatory behaviour with respect to Ca2+ mobilization; responses originating within the NPE are easily transferred to the PE, while the reverse does not occur.
Collapse
Affiliation(s)
- M Schütte
- Department of Ophthalmology, Mount Sinai School of Medicine, New York, NY 10029, USA.
| | | |
Collapse
|
46
|
|
47
|
Supuran CT, Barboiu M, Luca C, Pop E, Brewster ME, Dinculescu A. Carbonic anhydrase activators. Part 14. Syntheses of mono and bis pyridinium salt derivatives of 2-amino-5-(2-aminoethyl)- and 2-amino-5-(3-aminopropyl)-1,3,4-thiadiazole and their interaction with isozyme II. Eur J Med Chem 1996. [DOI: 10.1016/0223-5234(96)89555-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
48
|
Pate DW, Järvinen K, Urtti A, Jarho P, Järvinen T. Ophthalmic arachidonylethanolamide decreases intraocular pressure in normotensive rabbits. Curr Eye Res 1995; 14:791-7. [PMID: 8529418 DOI: 10.3109/02713689508995801] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Arachidonylethanolamide (AEA) was the first anandamide to be identified as an endogenous ligand for the cannabinoid receptor of porcine brain. Since cannabinoids have shown some value in the reduction of ocular hypertension, the title compound was evaluated in normotensive rabbits as a possible topically applied agent for reducing intraocular pressure. AEA was dissolved in an aqueous solution of 2-hydroxy-propyl-beta-cyclodextrin. Single eyedrops (25 microliters) containing 3.13, 6.25, 31.25, 62.5 or 125.0 micrograms of AEA were instilled unilaterally into eyes of normotensive albino and pigmented rabbits. The intraocular pressures (IOPs) of these rabbits were then measured at fixed time intervals. The effect of AEA on IOP in treated and untreated (contralateral) eyes was similar in both types of rabbits. Administration of 31.25 micrograms of AEA caused an immediate IOP reduction in the treated eyes. AEA doses of 62.5 micrograms caused an initial increase and subsequent decrease of IOP in the treated eyes. In the untreated eyes, a marginal ocular hypotensive response of limited duration occurred immediately after administration of AEA at doses 31.25 or 62.5 micrograms. A significant increase (without subsequent decrease below baseline) in IOP occurred in treated eyes after a dose of 125.0 micrograms. The lowest dose (3.13 micrograms) did not have an effect on IOP. This study constitutes the first published demonstration that topical, unilateral administration of AEA significantly decreases IOP in normotensive albino and pigmented rabbits. Although the mechanism of action by which this compound produces its hypotensive effect in the eye is not known, the results suggest that AEA may prove useful in the investigation of glaucoma therapy.
Collapse
Affiliation(s)
- D W Pate
- HortaPharm B.V., Amsterdam, The Netherlands
| | | | | | | | | |
Collapse
|
49
|
|
50
|
Sugrue MF, Mallorga P, Schwam H, Baldwin JJ, Ponticello GS. A comparison of L-671,152 and MK-927, two topically effective ocular hypotensive carbonic anhydrase inhibitors, in experimental animals. Curr Eye Res 1990; 9:607-15. [PMID: 2117519 DOI: 10.3109/02713689008999600] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
L-671,152 is a water-soluble, carbonic anhydrase inhibitor structurally similar to MK-927, a carbonic anhydrase inhibitor that, on topical administration, lowers the intraocular pressure (IOP) of experimental animals and humans. L-671,152 was more potent than MK-927 at inhibiting purified, human erythrocyte carbonic anhydrase II in vitro, as reflected in their respective IC50 values of 0.16 nM and 1.19 nM. Both compounds were compared for topical, ocular hypotensive activity in pigmented rabbits and cynomolgus monkeys. Ocular hypertension was induced in the latter by argon laser photocoagulation of the trabecular meshwork. A 2% solution of L-671,152 was more potent than 2% MK-927 in lowering the IOP of ocular hypertensive monkeys, the maximum reductions being 13.8 mm Hg (37%) and 9.6 mm Hg (27%) at 5 hr and 4 hr, respectively. Moreover, the duration of action of L-671,152 was superior to that of MK-927. The ocular hypotensive effect of L-671,152 was greater than that of MK-927 over a range of concentrations (0.5%-2%) in pigmented rabbits whose IOP was inherently elevated. The peak declines in the IOP of these rabbits after the instillation of 2% solutions of L-671,152 and MK-927 were 6.1 mm Hg and 4.8 mm Hg, respectively. L-671,152 was very effective in lowering the elevated IOP of alpha-chymotrypsinized rabbits and the unilateral instillation of 0.5% L-671,152 into the contralateral eye failed to decrease the elevated IOP of the alpha-chymotrypsinized eye. This finding indicates that the site of action of topically applied L-671,152 is local. The enhancement in the potency of L-671,152 over MK-927 is attributed to a greater inhibition of carbonic anhydrase activity.
Collapse
Affiliation(s)
- M F Sugrue
- Merck Sharp and Dohme Research Laboratories, West Point, PA 19486
| | | | | | | | | |
Collapse
|