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Mitra S, Tati V, Basu S, Shukla S. Role of Mesenchymal Stem Cell-Derived Conditioned Medium in Modulating the Benzalkonium Chloride-Induced Cytotoxic Effects in Cultured Corneal Epithelial Cells In Vitro. Curr Eye Res 2024; 49:815-825. [PMID: 38646923 DOI: 10.1080/02713683.2024.2342355] [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: 09/18/2023] [Accepted: 04/09/2024] [Indexed: 04/23/2024]
Abstract
PURPOSE Benzalkonium chloride (BAK) is a common preservative in ophthalmic formulations that causes cytotoxic damage to the corneal epithelial cells. This study aims to explore the role of mesenchymal stem cell (MSC)-derived conditioned medium in modulating the BAK-induced cytotoxic effects in cultured human corneal epithelial cells (HCECs) as a cell-free therapeutic agent. METHODS The in vitro cultured HCECs derived from a HCE cell line were treated with BAK (0.001% and 0.005%, diluted in DMEM/F12, v/v) for 15 min, washed with 1xPBS, and allowed to recover for 24 h in human bone marrow MSC-derived conditioned medium (MSC-CM: undiluted (100%) and diluted (50%, v/v)). On the other hand, HCECs were co-incubated with BAK (0.005%, v/v) and MSC-CM (100% and 50%, v/v) for 24 h. The HCEC-derived conditioned medium (HCE-CM) was used as an optimal control for MSC-CM, whereas HCECs cultured in DMEM/F12 were used as a control. The DMEM/F12 was used as the base medium for the culture of HCECs and preparation of HCE- and MSC-CM. The role of MSC-CM in modulating the metabolic activity, cell death, epithelial repair, and proliferation, in BAK-treated HCECs was evaluated using MTT assay, Propidium iodide staining, scratch assay, and Ki-67 staining, respectively. RESULTS Compared to the control, recovery of BAK-treated (0.001% and 0.005%, for 15 min) HCECs in MSC-CM showed significantly reduced cell death with enhanced metabolic activity, epithelial repair, and proliferation. However, in comparison with HCE-CM, the beneficial effects of MSC-CM were predominantly observed at lower BAK concentration (0.001%, for 15 min). Whereas the co-incubation of BAK (0.005%) and MSC-CM for a longer duration (24 h) was marginally beneficial. CONCLUSIONS Our results suggest that the MSC-CM is effective in modulating the BAK-induced cell death, retardation of metabolic activity and proliferation in cultured HCECs, particularly at lower concentration (0.001%) and shorter exposure (15 min) of BAK.
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Affiliation(s)
- Sreya Mitra
- Prof. Brien Holden Eye Research Centre, Hyderabad Eye Research Foundation, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | - Vasudeva Tati
- Prof. Brien Holden Eye Research Centre, Hyderabad Eye Research Foundation, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | - Sayan Basu
- Prof. Brien Holden Eye Research Centre, Hyderabad Eye Research Foundation, L V Prasad Eye Institute, Hyderabad, Telangana, India
- Shantilal Shanghvi Cornea Institute, L V Prasad Eye Institute, Hyderabad, Telangana, India
- Sudhakar and Sreekanth Ravi Stem Cell Biology Laboratory, Centre for Ocular Regeneration, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | - Sachin Shukla
- Prof. Brien Holden Eye Research Centre, Hyderabad Eye Research Foundation, L V Prasad Eye Institute, Hyderabad, Telangana, India
- Sudhakar and Sreekanth Ravi Stem Cell Biology Laboratory, Centre for Ocular Regeneration, L V Prasad Eye Institute, Hyderabad, Telangana, India
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Umetsu A, Ida Y, Sato T, Furuhashi M, Ohguro H, Watanabe M. Benzalkonium chloride greatly deteriorates the biological activities of human corneal stroma fibroblasts in a concentration-dependent manner. Graefes Arch Clin Exp Ophthalmol 2024; 262:1847-1855. [PMID: 38133799 DOI: 10.1007/s00417-023-06325-5] [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: 09/12/2023] [Revised: 11/11/2023] [Accepted: 11/23/2023] [Indexed: 12/23/2023] Open
Abstract
BACKGROUND Corneal tissues indirectly obtain nutritional needs and oxygen to maintain their homeostasis, and therefore, benzalkonium chloride (BAC) containing ocular instillations for medical therapy may, in turn, induce toxic effects more than expected in corneal tissues, especially the inside stroma layer. METHODS To evaluate the effects of very low concentrations (10-8%, 10-6%, or 10-4%) of BAC on human corneal stroma, we used two-dimensional (2D) cultures of human corneal stromal fibroblast (HCSF) cells and carried out the following analyses: (1) cell viability measurements, (2) Seahorse cellular bio-metabolism analysis, and (3) the expression of ECM molecules and endoplasmic reticulum (ER) stress-related molecules. RESULTS In the absence and presence of 10-8%, 10-6%, or 10-4% concentrations of BAC, cell viability deteriorated and this deterioration was dose-dependent. The results showed that maximal mitochondrial respiration was decreased, the mRNA expression of most of ECM proteins was decreased, and ER stress-related molecules were substantially and dose-dependently down-regulated in HCSFs by the BAC treatment. CONCLUSIONS The findings reported herein indicate that the presence of BAC, even at such low concentrations, is capable of causing the deterioration of cellular metabolic functions and negatively affecting the response to ER stress in HCSF cells resulting in a substantially decreased cellular viability.
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Affiliation(s)
- Araya Umetsu
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Yosuke Ida
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Tatsuya Sato
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
- Department of Cellular Physiology and Signal Transduction, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Masato Furuhashi
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Hiroshi Ohguro
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Megumi Watanabe
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan.
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Arana E, Gonzalo A, Andollo N, Goñi-de-Cerio F, Gómez-Fernández P, Salado C, Hernández G, Suárez-Cortés T. The new preservative-free ophthalmic formulation of bilastine 0.6% preserves the ocular surface epithelial integrity in a comparative in vitro study. Sci Rep 2024; 14:9598. [PMID: 38671063 PMCID: PMC11053002 DOI: 10.1038/s41598-024-59190-5] [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: 01/10/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Allergic conjunctivitis (AC) is the most common form of allergic eye disease and an increasingly prevalent condition. Topical eye drop treatments are the usual approach for managing AC, although their impact on the ocular surface is not frequently investigated. The aim of this study was to perform a comparative physicochemical characterization, and in vitro biological evaluations in primary conjunctival and corneal epithelial cells of the new multidose preservative-free bilastine 0.6% and main commercially available eye drops. MTT assay was used to measure cell viability; oxidative stress was analyzed with a ROS-sensitive probe; and apoptosis was evaluated monitoring caspase 3/7 activation. Differences in pH value, osmolarity, viscosity and phosphate levels were identified. Among all formulations, bilastine exhibited pH, osmolarity and viscosity values closer to tear film (7.4, 300 mOsm/l and ~ 1.5-10 mPa·s, respectively), and was the only phosphates-free solution. Single-dose ketotifen did not induce ROS production, and single-dose azelastine and bilastine only induced a mild increase. Bilastine and single-dose ketotifen and azelastine showed high survival rates attributable to the absence of preservative in its formulation, not inducing caspase-3/7-mediated apoptosis after 24 h. Our findings support the use of the new bilastine 0.6% for treating patients with AC to preserve and maintain the integrity of the ocular surface.
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Affiliation(s)
- Eider Arana
- Research, Development and Innovation Department (R&D+I Department), Faes Farma, Av. Autonomía 10, 48940, Leioa, Bizkaia, Spain
- Department of Cell Biology and Histology, School of Medicine and Nursing, University of the Basque Country, Leioa, Spain
| | - Ana Gonzalo
- Research, Development and Innovation Department (R&D+I Department), Faes Farma, Av. Autonomía 10, 48940, Leioa, Bizkaia, Spain
| | - Noelia Andollo
- Department of Cell Biology and Histology, School of Medicine and Nursing, University of the Basque Country, Leioa, Spain
- Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Felipe Goñi-de-Cerio
- Biotechnology Area, GAIKER Technology Centre, Basque Research and Technology Alliance, Zamudio, Spain
| | - Paloma Gómez-Fernández
- Biotechnology Area, GAIKER Technology Centre, Basque Research and Technology Alliance, Zamudio, Spain
| | - Clarisa Salado
- Innoprot SL, Bizkaia Technology Park, Derio, Bizkaia, Spain
| | - Gonzalo Hernández
- Research, Development and Innovation Department (R&D+I Department), Faes Farma, Av. Autonomía 10, 48940, Leioa, Bizkaia, Spain
| | - Tatiana Suárez-Cortés
- Research, Development and Innovation Department (R&D+I Department), Faes Farma, Av. Autonomía 10, 48940, Leioa, Bizkaia, Spain.
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Watanabe M, Sato T, Umetsu A, Nishikiori N, Higashide M, Furuhashi M, Ohguro H. Differential Effects of Benzalkonium Chloride on Human Trabecular Meshwork Cells Not Treated or Treated with Transforming Growth Factor-β2 or Dexamethasone. J Ocul Pharmacol Ther 2024; 40:189-196. [PMID: 38502813 DOI: 10.1089/jop.2023.0136] [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: 03/21/2024] Open
Abstract
Purpose: The objective of the present study was to evaluate the effects of low concentrations of benzalkonium chloride (BAC) (10-7%, 10-6%, or 10-5%) on healthy and glaucomatous human trabecular meshwork (HTM) cells. For this purpose, we used in vitro models replicating a healthy HTM and HTM with primary open-angle glaucoma (POAG) or steroid-induced glaucoma (SG) using two-dimensional (2D) cultures of HTM cells not treated or treated with a 5 ng/mL solution of transforming growth factor-β2 or 250 nM dexamethasone (DEX). Methods: Analyses were carried out for (1) the intercellular affinity function of 2D HTM monolayers, as determined by transepithelial electrical resistance (TEER) measurements; (2) cell viability; (3) cellular metabolism by using a Seahorse bioanalyzer; and (4) expression of extracellular matrix (ECM) molecules, an ECM modulator, and cell junction-related molecules. Results: In the absence and presence of BAC (10-7% or 10-5%), intercellular affinity function determined by TEER and cellular metabolic activities were significantly and dose dependently affected in both healthy and glaucomatous HTM cells despite the fact that there was no significant decrease in cell viabilities. However, the effects based on TEER values were significantly greater in the healthy HTM. The mRNA expression of several molecules that were tested was not substantially modulated by these concentrations of BAC. Conclusions: The findings reported herein suggest that low concentrations of BAC may have unfavorable adverse effects on cellular metabolic capacity by inducing increases in the intercellular affinity properties of the HTM, but those effects of BAC were different in healthy and glaucomatous HTM cells.
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Affiliation(s)
- Megumi Watanabe
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Tatsuya Sato
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
- Department of Cellular Physiology and Signal Transduction, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Araya Umetsu
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Nami Nishikiori
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Megumi Higashide
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Masato Furuhashi
- Department of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Hiroshi Ohguro
- Department of Ophthalmology, Sapporo Medical University School of Medicine, Sapporo, Japan
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Benzalkonium Chloride, Even at Low Concentrations, Deteriorates Intracellular Metabolic Capacity in Human Conjunctival Fibroblasts. Biomedicines 2022; 10:biomedicines10092315. [PMID: 36140416 PMCID: PMC9496331 DOI: 10.3390/biomedicines10092315] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/11/2022] [Accepted: 09/14/2022] [Indexed: 11/28/2022] Open
Abstract
The objective of this study was to clarify the effects of benzalkonium chloride (BAC) on two-dimensional (2D) and three-dimensional (3D) cultures of human conjunctival fibroblast (HconF) cells, which are in vitro models replicating the epithelial barrier and the stromal supportive functions of the human conjunctiva. The cultured HconF cells were subjected to the following analyses in the absence and presence of 10−5% or 10−4% concentrations of BAC; (1) the barrier function of the 2D HconF monolayers, as determined by trans-endothelial electrical resistance (TEER) and FITC dextran permeability, (2) real-time metabolic analysis using an extracellular Seahorse flux analyzer, (3) the size and stiffness of 3D HconF spheroids, and (4) the mRNA expression of genes that encode for extracellular matrix (ECM) molecules including collagen (COL)1, 4 and 6, and fibronectin (FN), α-smooth muscle actin (α-SMA), ER stress related genes including the X-box binding protein-1 (XBP1), the spliced XBP1 (sXBP1) glucose regulator protein (GRP)78, GRP94, and the CCAAT/enhancer-binding protein homologous protein (CHOP), hypoxia inducible factor 1α (HIF1α), and Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α). In the presence of BAC, even at low concentrations at 10−5% or 10−4%, the maximal respiratory capacity, mitochondrial respiratory reserve, and glycolytic reserve of HconF cells were significantly decreased, although the barrier functions of 2D HconF monolayers, the physical properties of the 3D HconF spheroids, and the mRNA expression of the corresponding genes were not affected. The findings reported herein highlight the fact that BAC, even such low concentrations, may induce unfavorable adverse effects on the cellular metabolic capacity of the human conjunctiva.
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Zhou X, Zhang X, Zhou D, Zhao Y, Duan X. A Narrative Review of Ocular Surface Disease Related to Anti-Glaucomatous Medications. Ophthalmol Ther 2022; 11:1681-1704. [PMID: 35943668 PMCID: PMC9437175 DOI: 10.1007/s40123-022-00557-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 07/29/2022] [Indexed: 01/31/2023] Open
Abstract
Topical anti-glaucomatous medications are still the most important measure to lower intraocular pressure. Large number of studies have confirmed that long-term use of anti-glaucomatous eye drops, especially containing benzalkonium chloride, a preservative, can cause or aggravate ocular surface injury. Ocular surface diseases damage the ocular microenvironmental health status, reduce the patients’ compliance with the treatment, and finally affect the treatment result. Therefore, the ocular surface management of patients with glaucoma is very important. This includes the selection of drugs that are better tolerated according to individual conditions, preservative-free formulations, drugs that protect against ocular surface disease, or selecting surgery and laser treatment, to prevent the damage to the ocular surface by topical anti-glaucomatous drugs.
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Affiliation(s)
- Xiaoyu Zhou
- Changsha Aier Eye Hospital, Changsha, Hunan Province, China.,The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Xinyue Zhang
- Changsha Aier Eye Hospital, Changsha, Hunan Province, China.,The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Dengming Zhou
- The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Yang Zhao
- Changsha Aier Eye Hospital, Changsha, Hunan Province, China.,The Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Xuanchu Duan
- Changsha Aier Eye Hospital, Changsha, Hunan Province, China. .,Aier School of Ophthalmology, Central South University, Changsha, Hunan Province, China.
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Zhong Y, Fang X, Wang X, Lin YA, Wu H, Li C. Effects of Sodium Hyaluronate Eye Drops With or Without Preservatives on Ocular Surface Bacterial Microbiota. Front Med (Lausanne) 2022; 9:793565. [PMID: 35252237 PMCID: PMC8896347 DOI: 10.3389/fmed.2022.793565] [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: 10/12/2021] [Accepted: 01/24/2022] [Indexed: 12/16/2022] Open
Abstract
Purpose This study aimed to determine the composition and diversity of bacterial communities on the ocular surface before and after the intervention with sodium hyaluronate eye drops (with or without preservatives) using 16S rRNA gene amplicon sequencing. Methods Sixteen healthy adults were randomly divided into two groups and treated with sodium hyaluronate eye drops with or without preservatives for 2 weeks. The individuals used the same artificial tears in both eyes. The microbial samples from the conjunctival sac of each participant were collected at baseline and 2 weeks after intervention. The diversity and taxonomic differences among different groups before and after intervention were compared by sequencing the V3–V4 region of the 16S rRNA gene. Results The similarity in the binocular microbial community was high in 1 of the 16 volunteers (Bray-Curtis dissimilarity score < 0.3). At the genus level, 11 bacteria were detected in all samples with an average relative abundance of more than 1%. The bacterial community changed significantly after the use of sodium hyaluronate eye drops (with or without preservatives), whether within individuals or between individuals in different groups (P < 0.05, PERMANOVA). Different dosage forms of sodium hyaluronate eye drops significantly decreased the relative abundance of Flavobacterium caeni and Deinococcus antarcticus, respectively (P < 0.05). Conclusions Healthy people had a rich diversity of the bacterial microbiota on the ocular surface, but the bacterial communities between the eyes were not completely similar. Irrespective of containing benzalkonium chloride (BAC), sodium hyaluronate eye drops can change the bacterial community on the ocular surface.
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Affiliation(s)
- Yanlin Zhong
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
| | - Xie Fang
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
| | - Xuemei Wang
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
| | - Yu-An Lin
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
| | - Huping Wu
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
- Huping Wu
| | - Cheng Li
- Eye Institute & Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science & Ocular Surface and Corneal Diseases, Xiamen, China
- *Correspondence: Cheng Li
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Comparison of Isohelix™ and Rayon swabbing systems for touch DNA recovery from metal surfaces. Forensic Sci Med Pathol 2021; 17:577-584. [PMID: 34674113 PMCID: PMC8528942 DOI: 10.1007/s12024-021-00423-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2021] [Indexed: 01/11/2023]
Abstract
A previous study evaluating two swabbing systems found that DNA was best recovered from sterile metal substrates using an Isohelix™ swab wetted with isopropyl alcohol rather than a Rayon swab with water as the wetting agent. We tested the same swabbing systems on metal (aluminum, brass, and stainless steel) and plastic substrates in a regularly touched environment to simulate the non-deliberate transfer of touch evidence likely seen in a casework scenario, to ascertain the performance of these swabs in an uncontrolled situation. Higher amounts of touch DNA were recovered with Isohelix™ swabs (0.5 – 3.3 ng) compared to Rayon swabs (0.13 – 1.2 ng). The Isohelix™ swabbing system was found to significantly recover more touch DNA (p = 0.04) from the metal substrates than the Rayon swabbing system, consistent with the findings of our previous work. The results contribute to our understanding of the impact of sample collection techniques on touch DNA recovery from problematic metal surfaces and suggest that supplemental cleaning of substrates as a precautionary step against the spread of infections may affect touch DNA persistence and the recovery efficiency of swabs.
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Paluch E, Szperlik J, Lamch Ł, Wilk KA, Obłąk E. Biofilm eradication and antifungal mechanism of action against Candida albicans of cationic dicephalic surfactants with a labile linker. Sci Rep 2021; 11:8896. [PMID: 33903615 PMCID: PMC8076202 DOI: 10.1038/s41598-021-88244-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 04/07/2021] [Indexed: 12/01/2022] Open
Abstract
Our research aims to expand the knowledge on relationships between the structure of cationic dicephalic surfactants—N,N-bis[3,3_-(dimethylamine)propyl]alkylamide dihydrochlorides and N,N-bis[3,3_-(trimethylammonio)propyl]alkylamide dibromides (alkyl: n-C9H19, n-C11H23, n-C13H27, n-C15H31)—and their antifungal mechanism of action on Candida albicans. The mentioned groups of amphiphilic substances are characterized by the presence of a weak, hydrochloride cationic center readily undergoing deprotonation, as well as a stable, strong quaternary ammonium group and alkyl chains capable of strong interactions with fungal cells. Strong fungicidal properties and the role in creation and eradication of biofilm of those compounds were discussed in our earlier works, yet their mechanism of action remained unclear. It was shown that investigated surfactants induce strong oxidative stress and cause increase in cell membrane permeability without compromising its continuity, as indicated by increased potassium ion (K+) leakage. Thus experiments carried out on the investigated opportunistic pathogen indicate that the mechanism of action of the researched surfactants is different than in the case of the majority of known surfactants. Results presented in this paper significantly broaden the understanding on multifunctional cationic surfactants and their mechanism of action, as well as suggest their possible future applications as surface coating antiadhesives, fungicides and antibiofilm agents in medicine or industry.
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Affiliation(s)
- Emil Paluch
- Department of Microbiology, Faculty of Medicine, Wroclaw Medical University, Tytusa Chałubińskiego 4, 50-376, Wrocław, Poland.
| | - Jakub Szperlik
- Department of Genetic Biochemistry, Faculty of Biotechnology, University of Wroclaw, Przybyszewskiego 63, 51-148, Wrocław, Poland
| | - Łukasz Lamch
- Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Kazimiera A Wilk
- Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Ewa Obłąk
- Department Physicochemistry of Microorganisms, Faculty of Biological Sciences, University of Wrocław, Przybyszewskiego 63/77, 51-148, Wrocław, Poland.
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Bíró T, Bocsik A, Jurišić Dukovski B, Gróf I, Lovrić J, Csóka I, Deli MA, Aigner Z. New Approach in Ocular Drug Delivery: In vitro and ex vivo Investigation of Cyclodextrin-Containing, Mucoadhesive Eye Drop Formulations. DRUG DESIGN DEVELOPMENT AND THERAPY 2021; 15:351-360. [PMID: 33568896 PMCID: PMC7868180 DOI: 10.2147/dddt.s264745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 11/18/2020] [Indexed: 01/31/2023]
Abstract
Background Optimal transcorneal penetration is necessary for ocular therapy; meanwhile, it is limited by the complex structure and defensive mechanisms of the eye. Antimicrobial stability of topical ophthalmic formulations is especially important. According to previous studies, the mostly used preservative, benzalkonium-chloride is irritative and toxic on corneal epithelial cells; therefore, novel non-toxic, antimicrobial agents are required. In this study, prednisolone-containing ophthalmic formulations were developed with expected optimal permeation without toxic or irritative effects. Methods The toxicity and permeability of prednisolone-containing eye drops were studied on a human corneal epithelial cell line (HCE-T) and ex vivo cornea model. The lipophilic drug is dissolved by the formation of cyclodextrin inclusion complex. Zinc-containing mucoadhesive biopolymer was applied as an alternative preservative agent, whose toxicity was compared with benzalkonium-chloride. Results As the results show, benzalkonium-chloride-containing samples were toxic on HCE-T cells. The biopolymer caused no cell damage after the treatment. This was confirmed by immunohistochemistry assay. The in vitro permeability was significantly higher in formulations with prednisolone-cyclodextrin complex compared with suspension formulation. According to the ex vivo permeability study, the biopolymer-containing samples had significantly lower permeability. Conclusion Considering the mucoadhesive attribute of target formulations, prolonged absorption is expected after application with less frequent administration. It can be stated that the compositions are innovative approaches as novel non-toxic ophthalmic formulations with optimal drug permeability.
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Affiliation(s)
- Tivadar Bíró
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
| | - Alexandra Bocsik
- Institute of Biophysics, Biological Research Centre,, Szeged, Hungary
| | - Bisera Jurišić Dukovski
- Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Ilona Gróf
- Institute of Biophysics, Biological Research Centre,, Szeged, Hungary.,Doctoral School of Biology, University of Szeged, Szeged, Hungary
| | - Jasmina Lovrić
- Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia
| | - Ildikó Csóka
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
| | - Mária A Deli
- Institute of Biophysics, Biological Research Centre,, Szeged, Hungary
| | - Zoltán Aigner
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, Szeged, Hungary
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Figus M, Agnifili L, Lanzini M, Brescia L, Sartini F, Mastropasqua L, Posarelli C. Topical preservative-free ophthalmic treatments: an unmet clinical need. Expert Opin Drug Deliv 2020; 18:655-672. [PMID: 33280452 DOI: 10.1080/17425247.2021.1860014] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction: The main role of preservatives in eyedrops is to ensure sterility and microbiological integrity of the drug, and to facilitate the penetration of active compounds into the eye. However, several studies documented significant toxic effects induced by preservatives, especially on the ocular surface. Consequently, most of the ophthalmic medications became progressively available in preservative-free (PF) formulations.Areas covered: We analyzed pre-clinical and clinical studies on PF eyedrops with particular attention to common chronic diseases such as dry eye and glaucoma. We discussed about the pros and cons of using PF eyedrops, in terms of efficacy, safety, and social-economic aspects.Expert opinion: There are still unresolved issues that make hard for PF medications to definitively conquer the drug market. Despite robust pre-clinical evidences of less toxicity, the low number of randomized clinical trials does not permit to state that PF eyedrops have, in clinical practice, a similar efficacy or a higher safety compared to preserved forms. These aspects limit their use to chronic diseases requiring long-term therapies with multiple daily instillations, especially in the presence of concomitant ophthalmic diseases that expose to a risk of ocular surface worsening.
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Affiliation(s)
- Michele Figus
- Ophthalmology, Department of Surgical, Medical, Molecular Pathology and of Critical Area, University of Pisa, Pisa, Italy
| | - Luca Agnifili
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Manuela Lanzini
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Lorenza Brescia
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Francesco Sartini
- Ophthalmology, Department of Surgical, Medical, Molecular Pathology and of Critical Area, University of Pisa, Pisa, Italy
| | - Leonardo Mastropasqua
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Chiara Posarelli
- Ophthalmology, Department of Surgical, Medical, Molecular Pathology and of Critical Area, University of Pisa, Pisa, Italy
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Souto EB, Campos JR, Da Ana R, Martins-Gomes C, Silva AM, Souto SB, Lucarini M, Durazzo A, Santini A. Ocular Cell Lines and Genotoxicity Assessment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E2046. [PMID: 32204489 PMCID: PMC7142522 DOI: 10.3390/ijerph17062046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/10/2020] [Accepted: 03/16/2020] [Indexed: 12/20/2022]
Abstract
Genotoxicity screening tests aim to evaluate if and to what extent a compound in contact with the human body (e.g., a drug molecule, a compound from the environment) interacts with DNA. The comet assay is a sensitive method used to predict the risk of DNA damage in individual cells, as it quantifies the tape breaks, being the alkaline version (pH > 13) the most commonly used in the laboratory. Epithelial cells serve as biomatrices in genotoxicity assessments. As ca. 80% of solid cancers are of epithelial origin, the quantification of the DNA damage upon exposure of epithelial cells to a drug or drug formulation becomes relevant. Comet assays run in epithelial cells also have clinical applications in human biomonitoring, which assesses whether and to what extent is the human body exposed to environmental genotoxic compounds and how such exposure changes over time. Ocular mucosa is particularly exposed to environmental assaults. This review summarizes the published data on the genotoxicity assessment in estimating DNA damage in epithelial cells with a special focus on ocular cell lines. General comet assay procedures for ex vivo and in vivo epithelium samples are also described.
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Affiliation(s)
- Eliana B. Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; (J.R.C.); (R.D.A.)
- CEB-Centre of Biological Engineering, University of Minho, Campus de Gualtar 4710-057 Braga, Portugal
| | - Joana R. Campos
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; (J.R.C.); (R.D.A.)
| | - Raquel Da Ana
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal; (J.R.C.); (R.D.A.)
| | - Carlos Martins-Gomes
- Department of Biology and Environment, University of Trás-os-Montes e Alto Douro, UTAD, Quinta de Prados, P-5001-801 Vila Real, Portugal; (C.M.-G.); (A.M.S.)
- Centre for Research and Technology of Agro-Environmental and Biological Sciences, CITAB, UTAD, Quinta de Prados, P-5001-801 Vila Real, Portugal
| | - Amélia M. Silva
- Department of Biology and Environment, University of Trás-os-Montes e Alto Douro, UTAD, Quinta de Prados, P-5001-801 Vila Real, Portugal; (C.M.-G.); (A.M.S.)
- Centre for Research and Technology of Agro-Environmental and Biological Sciences, CITAB, UTAD, Quinta de Prados, P-5001-801 Vila Real, Portugal
| | - Selma B. Souto
- Department of Endocrinology of Hospital de São João, Alameda Prof. Hernâni Monteiro, 4200–319 Porto, Portugal;
| | - Massimo Lucarini
- CREA-Research Centre for Food and Nutrition, Via Ardeatina 546, 00178 Rome, Italy; (M.L.); (A.D.)
| | - Alessandra Durazzo
- CREA-Research Centre for Food and Nutrition, Via Ardeatina 546, 00178 Rome, Italy; (M.L.); (A.D.)
| | - Antonello Santini
- Department of Pharmacy, University of Napoli Federico II, Via D. Montesano 49, 80131 Napoli, Italy
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Zhang R, Park M, Richardson A, Tedla N, Pandzic E, de Paiva CS, Watson S, Wakefield D, Di Girolamo N. Dose-dependent benzalkonium chloride toxicity imparts ocular surface epithelial changes with features of dry eye disease. Ocul Surf 2019; 18:158-169. [PMID: 31740391 DOI: 10.1016/j.jtos.2019.11.006] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/15/2019] [Accepted: 11/13/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE Inclusion of the preservative benzalkonium chloride (BAC) in ophthalmic solutions is prevalent, despite the noted potential for exacerbating dry eye disease (DED). Whilst studies incorporating BAC have assessed its' effects as a mouse model of DED, the impact on limbal epithelia is under-studied. Our investigation aimed to comprehensively assess the impact of different BAC dosing regimens and their suitability as a mouse model of DED. METHODS C57BL/6J mice (n = 72) were administered topical BAC (0.05-0.2%) over 7 days. Fluorescein staining, corneal smoothness index, and immuno-histological analyses were applied to determine architectural and cellular changes on the ocular surface following BAC treatment. The effect of BAC (0.0001-0.01%) on cultivated primary mouse corneo-limbal epithelial cells (CLECs) (n = 6) was examined using morphological and functional assays. RESULTS Whilst 0.2% BAC induced severe corneal epithelial defects, 0.1% BAC dispensed once daily over 7 days, induced punctate fluorescein staining without detriment to corneal smoothness. Histochemical staining revealed disorganized basal corneal epithelial cells with enlarged cytoplasmic halos. Furthermore, PAS+ goblet cells were decreased. BAC treatment also modulated K14 expression and distribution within the limbus. In cultured CLEC, BAC triggered cell contraction and vacuolation, increased LDH release and elevated cell necrosis by 4.1-fold. Concentrations of BAC as low as 0.0001% decreased colony formation. CONCLUSIONS This study describes how exposing C57BL/6 mice to BAC induce some clinicopathological features of DED seen in humans, and therefore provides the foundations to explore the consequences on the ocular surface, particularly on limbal epithelia and its' stem cells.
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Affiliation(s)
- Richard Zhang
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia
| | - Mijeong Park
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia
| | - Alexander Richardson
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia
| | - Nicodemus Tedla
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia
| | - Elvis Pandzic
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW, 2052, Australia
| | - Cintia S de Paiva
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, 77030, United States
| | - Stephanie Watson
- Save Sight Institute, Discipline of Ophthalmology, Sydney Medical School, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Denis Wakefield
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia
| | - Nick Di Girolamo
- Mechanisms of Disease and Translational Research, School of Medical Sciences, Faculty of Medicine, University of NSW, Sydney, NSW, 2052, Australia.
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Abstract
PURPOSE This study examines the impact of corneal surface lubricants used during pars plana vitrectomy on corneal edema. METHODS This prospective, observational, clinical study occurred at an academic institution. Participants were individuals aged 18 years and older who had already consented to undergo pars plana vitrectomy, without pre-existing corneal pathology. A corneal lubricant was chosen by the surgeon. Corneal thickness was measured preoperatively and postoperatively using pachymetry and anterior segment optical coherence tomography (AS-OCT). Main outcome measure was change in corneal thickness as measured by pachymetry. RESULTS Forty-one patients completed the study protocol. The 23 subjects in the SHCS group had a significantly smaller increase in corneal thickness as measured by pachymetry compared with the 18 subjects in the HPMC group (29.9 μm vs. 58.1 μm, P value 0.02). When measured by anterior segment optical coherence tomography, the SHCS group had a smaller increase in corneal thickness compared with the HPMC group (0.04 mm vs. 0.06 mm, P value 0.09) but did not reach significance. CONCLUSION SHCS is associated with reduced postoperative increase in corneal pachymetry as compared to HPMC.
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Effects of benzalkonium chloride on cell viability, inflammatory response, and oxidative stress of human alveolar epithelial cells cultured in a dynamic culture condition. Toxicol In Vitro 2019; 59:221-227. [DOI: 10.1016/j.tiv.2019.04.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 03/30/2019] [Accepted: 04/24/2019] [Indexed: 11/22/2022]
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Tahara H, Sadamoto K, Yamagiwa Y, Nemoto S, Kurata M. Investigation of comet assays under conditions mimicking ocular instillation administration in a three-dimensional reconstructed human corneal epithelial model. Cutan Ocul Toxicol 2019; 38:375-383. [PMID: 31223032 DOI: 10.1080/15569527.2019.1634580] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Purpose: A comet assay is one of the genotoxicity methods for evaluating the potential of chemicals to induce DNA strand breaks. To investigate the usefulness of comet assays for evaluating the genotoxic potential of ophthalmic solutions, a three-dimensional (3D) reconstructed human corneal epithelial model (3D corneal model) was exposed to conditions mimicking topical ocular instillation administration. Methods: The 3D corneal model was exposed to acridine orange, ethidium bromide, hydrogen peroxide, 1,1'-dimethyl-4,4'-bipyridinium dichloride (paraquat), 4-nitroquinoline 1-oxide (4-NQO), acrylamide and methyl methanesulfonate (MMS). To mimic the ocular surface condition to which ophthalmic solutions are administered, the exposure time was set to 1 minute. Likewise, human corneal epithelial (HCE-T) cells, as monolayer cultured cells, were exposed to the same chemicals, for comparison. Results: In the 3D corneal model, the amount of DNA fragments was statistically significantly increased in cells treated with each of the test chemicals except acrylamide. In HCE-T cells, the amount of DNA fragments was statistically significantly increased in acridine orange-, ethidium bromide-, hydrogen peroxide-, 4-NQO- and MMS-treated cells but not in paraquat- or acrylamide-treated cells. In the 3D corneal model, the lowest concentrations at which we observed DNA damage were about 100 times higher than the concentrations in HCE-T cells. Since the 3D corneal model is morphologically similar to human corneal tissue, form a multilayer and having tight junctions, it may be that the test chemicals only permeated about 1% into the 3D corneal model. Conclusion: These results suggest that the comet assay using 3D cell culture models may reflect in vivo conditions better than do monolayer cultured cells, and that the comet assay may be useful for the evaluation of genotoxic potential of topical ophthalmic solution.
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Affiliation(s)
- Haruna Tahara
- Research and Development Division, Senju Pharmaceutical Co., Ltd , Kobe , Hyogo , Japan
| | - Kazuyo Sadamoto
- Research and Development Division, Senju Pharmaceutical Co., Ltd , Kobe , Hyogo , Japan
| | - Yoshinori Yamagiwa
- Research and Development Division, Senju Pharmaceutical Co., Ltd , Kobe , Hyogo , Japan
| | - Shingo Nemoto
- Research and Development Division, Senju Pharmaceutical Co., Ltd , Kobe , Hyogo , Japan
| | - Masaaki Kurata
- Research and Development Division, Senju Pharmaceutical Co., Ltd , Kobe , Hyogo , Japan
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Bíró T, Horvát G, Budai-Szűcs M, Csányi E, Urbán E, Facskó A, Szabó-Révész P, Csóka I, Aigner Z. Development of prednisolone-containing eye drop formulations by cyclodextrin complexation and antimicrobial, mucoadhesive biopolymer. DRUG DESIGN DEVELOPMENT AND THERAPY 2018; 12:2529-2537. [PMID: 30147300 PMCID: PMC6101011 DOI: 10.2147/dddt.s165693] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Purpose The formulation of topical ophthalmic products with appropriate therapeutic effect and patient compliance is a major challenge. To increase the efficiency of the ocular delivery of the drug, the enhancement of water solubility and the contact time of the drug on the surface of the cornea are necessary. In this work, prednisolone (PR)-containing eye drops were formulated with antimicrobial, mucoadhesive biopolymer and PR-cyclodextrin inclusion complex. This approach can be used for the development of innovative ophthalmic formulations. Materials and methods After adjusting the optimal physiological parameters, the amount of the required cyclodextrin for the highest penetration of PR was determined by dialysis membrane diffusion study. The viscosity, surface tension and mucoadhesion of the eye drops were measured. The microbiological effectiveness of zinc-hyaluronate (ZnHA) was investigated by a standard method of the European Pharmacopoeia. Results In this case, no significant difference of surface tension was measured in products with different amounts of cyclodextrin. According to the results of the tensile test, ZnHA as a mucoadhesive biopolymer improves the mucoadhesion of ophthalmic products. The antimicrobial stability of formulations preserved by ZnHA meets requirement B of the European Pharmacopoeia. Conclusion It can be stated that the innovative PR-containing compositions are suitable for producing mucoadhesive, properly preserved aqueous ophthalmic solutions with increased bioavailability attributes.
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Affiliation(s)
- Tivadar Bíró
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Gabriella Horvát
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Mária Budai-Szűcs
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Erzsébet Csányi
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Edit Urbán
- Department of Clinical Microbiology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Andrea Facskó
- Ophthalmology Department, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - Piroska Szabó-Révész
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Ildikó Csóka
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
| | - Zoltán Aigner
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary,
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Steven DW, Alaghband P, Lim KS. Preservatives in glaucoma medication. Br J Ophthalmol 2018; 102:1497-1503. [PMID: 29973365 PMCID: PMC6241623 DOI: 10.1136/bjophthalmol-2017-311544] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 04/05/2018] [Accepted: 05/12/2018] [Indexed: 11/04/2022]
Abstract
Preservatives continue to be in widespread use in ophthalmic medications due to the convenience they provide, regulatory requirements and the higher cost of alternatives. Benzalkonium chloride (BAK) remains the most commonly used preservative but there is a trend towards the use of preservative-free (PF) drops for glaucoma, although at a higher price. An extensive body of literature explores BAK toxicity on ocular structures in animal and laboratory studies (in vitro and in vivo). Non-randomised controlled studies have provided some supporting evidence of its toxicity in patients, especially in those with pre-existing ocular surface disease (OSD) or on multiple medications. However, there have been very few randomised controlled trials that compare the same medication with and without BAK preservative. Several of these trials have never been published in any peer reviewed journals. Notwithstanding, those that have been published, have not demonstrated any clear benefits of the BAK-free formulations. Short duration and exclusion of those with OSD are limitations of these studies. There is a lack of evidence of clinically significant harm from a small number of BAK preserved drops in patients without OSD. This means that generally more expensive PF glaucoma medications should only be recommended for those on poly pharmacy or those with OSD but are not necessarily required for all patients.
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Affiliation(s)
- David W Steven
- Department of Ophthalmology, Eerste River and Groote Schuur Hospitals, University of Cape Town, Cape Town, South Africa
| | - Pouya Alaghband
- Department of Ophthalmology, Bradford Royal Infirmary, Bradford, UK
| | - Kin Sheng Lim
- Department of Ophthalmology, St Thomas' Hospital, London, UK
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Effects of 20% Human Serum on Corneal Epithelial Toxicity Induced by Benzalkonium Chloride: In Vitro and Clinical Studies. Cornea 2018; 37:617-623. [PMID: 29300263 DOI: 10.1097/ico.0000000000001475] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Benzalkonium chloride (BAK), the most commonly used preservative in ophthalmic solutions, is known to cause toxicity in the corneal epithelium. In this study, we investigated the effects of 20% human serum in cultures of BAK-damaged human corneal epithelial cells (hCECs) and in patients with toxic corneal epitheliopathy induced by BAK-containing eye drops. METHODS hCECs were exposed to various concentrations of BAK (0%, 0.002%, 0.02%, and 0.2%) in the presence or absence of 20% human serum. After 24 hours, the metabolic activity, proliferation, apoptosis, and proinflammatory cytokine expression were evaluated in the cells. Also, cell migration was assessed using a scratch test. In the clinical study, 24 patients with toxic corneal epitheliopathy secondary to BAK-containing antiglaucoma eye drops were treated with topical application of 20% autologous serum, and corneal epithelial integrity was evaluated. RESULTS BAK induced cytotoxicity in hCECs by inhibiting the metabolic activity, proliferation, and migration and by increasing apoptosis in a concentration-dependent manner. The level of proinflammatory cytokine IL-8 was elevated in BAK-treated cells. Addition of 20% human serum to the cultures significantly promoted the cell metabolic activity, proliferation, and migration while markedly reducing apoptosis. In line with the in vitro results, corneal punctate epithelial erosions were decreased from a National Eye Institute scale score of 4.2 ± 2.1 to 1.3 ± 1.7 in 20 of 24 patients (84%) after treatment with 20% autologous serum. CONCLUSIONS Data demonstrate that 20% human serum is effective in treating BAK-induced cytotoxicity in hCECs and provides a basis for using 20% autologous serum for patients with preservative-induced corneal epitheliopathy.
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Choi SM, Roh TH, Lim DS, Kacew S, Kim HS, Lee BM. Risk assessment of benzalkonium chloride in cosmetic products. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2017; 21:8-23. [PMID: 29211634 DOI: 10.1080/10937404.2017.1408552] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A risk assessment of benzalkonium chloride (BAC) was conducted based upon its toxicological profile and exposure evaluation. Since 1935, BAC has been used in a wide variety of products such as disinfectants, preservatives, and sanitizers. It is well-established that BAC is not genotoxic nor does it display tumorigenic potential, but safety concerns have been raised in local usage such as for ocular and intranasal applications. The Foundation of Korea Cosmetic Industry Institute (KCII) reported that in a hair conditioner manufactured as a cosmetic or personal product in South Korea, BAC was present at concentrations of 0.5-2%. The systemic exposure dosage (SED) was determined using the above in-use concentrations and a risk assessment analysis was conducted. The Margin of Safety (MOS) values for hair conditioners were calculated to be between 621 and 2,483. The risk of certain personal and cosmetic products was also assessed based upon assumptions that BAC was present at the maximal level of regulation in South Korea and that the maximal amount was used. The MOS values for the body lotion were all above 100, regardless of the application site. Collectively, data indicate that there are no safety concerns regarding use of products that contain BAC under the current concentration restrictions, even when utilized at maximal permitted levels. However, a chronic dermal toxicity study on BAC and comprehensive dermal absorption evaluation needs to be conducted to provide a more accurate prediction of the potential health risks to humans.
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Affiliation(s)
- Seul Min Choi
- a Division of Toxicology, College of Pharmacy , Sungkyunkwan University , Gyeonggi-Do , Suwon , South Korea
| | - Tae Hyun Roh
- a Division of Toxicology, College of Pharmacy , Sungkyunkwan University , Gyeonggi-Do , Suwon , South Korea
| | - Duck Soo Lim
- a Division of Toxicology, College of Pharmacy , Sungkyunkwan University , Gyeonggi-Do , Suwon , South Korea
| | - Sam Kacew
- b McLaughlin Centre for Population Health Risk Assessment , University of Ottawa , Ottawa , ON , Canada
| | - Hyung Sik Kim
- a Division of Toxicology, College of Pharmacy , Sungkyunkwan University , Gyeonggi-Do , Suwon , South Korea
| | - Byung-Mu Lee
- a Division of Toxicology, College of Pharmacy , Sungkyunkwan University , Gyeonggi-Do , Suwon , South Korea
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Aguayo Bonniard A, Yeung JY, Chan CC, Birt CM. Ocular surface toxicity from glaucoma topical medications and associated preservatives such as benzalkonium chloride (BAK). Expert Opin Drug Metab Toxicol 2016; 12:1279-1289. [PMID: 27398637 DOI: 10.1080/17425255.2016.1209481] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION This review discusses the evidence concerning the effect of topical medications and their preservatives on the ocular surface in glaucoma patients. The role of topical anti-glaucoma medication remains critical in the management of chronic glaucoma worldwide but the beneficial effects of treatment are counterbalanced by the adverse effects of corneal and conjunctival toxicity. Areas covered: This article covers the effect of topical ocular drops and preservatives, particularly benzalkonium chloride, on the cornea and conjunctiva. Both basic science and clinical evidence will be presented. The first part reviews the relationship between ocular surface disease and benzalkonium chloride and the evidence from non-benzalkonium chloride preserved drops. The second part discusses the effects of benzalkonium chloride on the histopathology of the conjunctiva and its impact on clinical care as well as quality of life. Expert opinion: Topical anti-glaucoma medication will continue to be used in the management of this blinding disease for the foreseeable future. Treatment outcomes will benefit from minimized exposure to benzalkonium chloride. The development of alternative preservatives, preservative-free topical options, and non-drop therapeutics such as drug-eluting systems for the delivery of ocular medications, will be very helpful in the care of glaucoma patients.
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Affiliation(s)
- Alberto Aguayo Bonniard
- a Department of Ophthalmology and Vision Sciences , University of Toronto , Toronto , Canada
| | - Jacky Y Yeung
- a Department of Ophthalmology and Vision Sciences , University of Toronto , Toronto , Canada.,b Department of Ophthalmology , Queen's University , Kingston , Ontario
| | - Clara C Chan
- a Department of Ophthalmology and Vision Sciences , University of Toronto , Toronto , Canada
| | - Catherine M Birt
- a Department of Ophthalmology and Vision Sciences , University of Toronto , Toronto , Canada
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Xu Y, Wang S, Miao Q, Jin K, Lou L, Ye X, Xi Y, Ye J. Protective Role of Hinokitiol Against H 2O 2-Induced Injury in Human Corneal Epithelium. Curr Eye Res 2016; 42:47-53. [PMID: 27269503 DOI: 10.3109/02713683.2016.1151530] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE We recently found that hinokitiol has anti-inflammatory activity in human corneal epithelial (HCE) cells. Herein, we investigated the protective role of hinokitiol against H2O2-induced injury in HCE cells and the mechanisms that underlie its action. METHODS HCE cells were incubated with different concentrations of hinokitiol or dimethylsulfoxide (DMSO), which served as a vehicle control, before H2O2 stimulus. The cell viability was evaluated using a cell counting kit-8 (CCK-8) assay. TUNEL, phosphorylated histone γH2A.X, cleaved caspase-3 expression analyses, and location of cytochrome c were conducted to detect cell injury and apoptosis. Reactive oxygen species (ROS), catalase (CAT), superoxide dismutase (SOD), methane dicarboxylic aldehyde (MDA), and total antioxidative capacity (T-AOC) were used to determine oxidative stress. Bcl-2 and Bax protein expressions were measured by western blotting. RESULTS Hinokitiol significantly improved the cell viability, decreased the apoptosis rate, inhibited DNA damage, and reduced cleaved caspase-3 expression and the leakage of cytochrome c from mimitochondrion to cytoplasm of HCE cells against the oxidative stress induced by H2O2. Generation of ROS and MDA and decreased activity of CAT, SOD, and T-AOC were also ameliorated by hinokitiol administration. Moreover, Bcl-2 expression was down-regulated while Bax was up-regulated by H2O2 stimulus, which were reversed by hinokitiol application. CONCLUSION Hinokitiol protects HCE cells against H2O2-induced injury likely by its antioxidant activity and modulating the Bcl-2 signaling pathway.
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Affiliation(s)
- Yufeng Xu
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Shengzhan Wang
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Qi Miao
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Kai Jin
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Lixia Lou
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Xin Ye
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Yan Xi
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
| | - Juan Ye
- a Department of Ophthalmology , The Second Affiliated Hospital of Zhejiang University, College of Medicine , Hangzhou , Zhejiang , China
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Ye J, Xu YF, Lou LX, Jin K, Miao Q, Ye X, Xi Y. Anti-inflammatory effects of hinokitiol on human corneal epithelial cells: an in vitro study. Eye (Lond) 2015; 29:964-71. [PMID: 25952949 DOI: 10.1038/eye.2015.62] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 03/08/2015] [Indexed: 12/29/2022] Open
Abstract
PURPOSE This study assessed the anti-inflammatory effect and mechanism of action of hinokitiol in human corneal epithelial (HCE) cells. METHODS HCE cells were incubated with different concentrations of hinokitiol or dimethylsulfoxide (DMSO), which served as a vehicle control. Cell viability was evaluated using Cell Counting Kit-8 (CCK-8) assay. After polyriboinosinic:polyribocytidylic acid (poly(I:C)) stimulus, cells with or without hinokitiol were evaluated for the mRNA and protein levels of interleukin-8 (IL-8), interleukin-6 (IL-6), and interleukin-1β (IL-1β) using real-time PCR analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Nuclear and cytoplasmic levels of nuclear factor kappa B (NF-κB) p65 protein and an inhibitor of NF-κB α (IκBα) were evaluated using western blotting. RESULTS There were no significant differences among the treatment concentrations of hinokitiol compared with cells incubated in medium only. Incubating with 100 μM hinokitiol significantly decreased the mRNA levels of IL-8 to 58.77±10.41% (P<0.01), IL-6 to 64.64±12.71% (P<0.01), and IL-1β to 54.19±8.10% (P<0.01) compared with cells stimulated with poly(I:C) alone. The protein levels of IL-8, IL-6, and IL-1β had similar trend. Further analysis revealed that hinokitiol maintained the levels of IκBα and significantly reduced NF-κB p65 subunit translocation to the nucleus which significantly inhibiting the activation of the NF-κB signal pathway. CONCLUSION Hinokitiol showed a significant protective effect against ocular surface inflammation through inhibiting the NF-κB pathway, which may indicate the possibility to relieve the ocular surface inflammation of dry eye syndrome (DES).
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Affiliation(s)
- J Ye
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - Y-F Xu
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - L-X Lou
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - K Jin
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - Q Miao
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - X Ye
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
| | - Y Xi
- Department of Ophthalmology, The Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, Zhejiang, China
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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
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Richoz O, Kling S, Hoogewoud F, Hammer A, Tabibian D, Francois P, Schrenzel J, Hafezi F. Antibacterial Efficacy of Accelerated Photoactivated Chromophore for Keratitis–Corneal Collagen Cross-linking (PACK-CXL). J Refract Surg 2014; 30:850-4. [DOI: 10.3928/1081597x-20141118-01] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 10/20/2014] [Indexed: 11/20/2022]
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Rojas E, Lorenzo Y, Haug K, Nicolaissen B, Valverde M. Epithelial cells as alternative human biomatrices for comet assay. Front Genet 2014; 5:386. [PMID: 25506353 PMCID: PMC4246922 DOI: 10.3389/fgene.2014.00386] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 10/22/2014] [Indexed: 01/01/2023] Open
Abstract
The comet assay is a valuable experimental tool aimed at mapping DNA damage in human cells in vivo for environmental and occupational monitoring, as well as for therapeutic purposes, such as storage prior to transplant, during tissue engineering, and in experimental ex vivo assays. Furthermore, due to its great versatility, the comet assay allows to explore the use of alternative cell types to assess DNA damage, such as epithelial cells. Epithelial cells, as specialized components of many organs, have the potential to serve as biomatrices that can be used to evaluate genotoxicity and may also serve as early effect biomarkers. Furthermore, 80% of solid cancers are of epithelial origin, which points to the importance of studying DNA damage in these tissues. Indeed, studies including comet assay in epithelial cells have either clear clinical applications (lens and corneal epithelial cells) or examine genotoxicity within human biomonitoring and in vitro studies. We here review improvements in determining DNA damage using the comet assay by employing lens, corneal, tear duct, buccal, and nasal epithelial cells. For some of these tissues invasive sampling procedures are needed. Desquamated epithelial cells must be obtained and dissociated prior to examination using the comet assay, and such procedures may induce varying amounts of DNA damage. Buccal epithelial cells require lysis enriched with proteinase K to obtain free nucleosomes. Over a 30 year period, the comet assay in epithelial cells has been little employed, however its use indicates that it could be an extraordinary tool not only for risk assessment, but also for diagnosis, prognosis of treatments and diseases.
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Affiliation(s)
- Emilio Rojas
- Depto. Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México México, México
| | - Yolanda Lorenzo
- Department of Ophthalmology, Center for Eye Research, Oslo University Hospital, Ullevål, University of Oslo Oslo, Norway
| | - Kristiane Haug
- Department of Ophthalmology, Center for Eye Research, Oslo University Hospital, Ullevål, University of Oslo Oslo, Norway
| | - Bjørn Nicolaissen
- Department of Ophthalmology, Center for Eye Research, Oslo University Hospital, Ullevål, University of Oslo Oslo, Norway
| | - Mahara Valverde
- Depto. Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México México, México
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Abe RY, Zacchia RS, Santana PR, Costa VP. Effects of benzalkonium chloride on the blood-aqueous and blood-retinal barriers of pseudophakic eyes. J Ocul Pharmacol Ther 2014; 30:413-8. [PMID: 24660827 DOI: 10.1089/jop.2013.0227] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To evaluate the effects of benzalkonium chloride (BAK) on the blood-aqueous (BAB) and blood-retinal barriers (BRB) of pseudophakic eyes. METHODS Prospective, randomized, investigator-masked, comparative study. Patients were randomly assigned to preservative-free artificial tears or BAK-preserved artificial tears. One drop of artificial tears was instilled 4 times a day in the study eye, starting the day after randomization for 30 days. Anterior chamber flare was assessed by a laser flare meter (LFM) and macular thickness measurements were obtained with optical coherence tomography, before, 15, and 30 days after randomization. RESULTS A total of 44 healthy eyes of 44 pseudophakic volunteers were recruited. There were no significant differences regarding demographics (age, gender, and race distributions) and clinical characteristics (eye, mean intraocular pressure, and mean best-corrected visual acuity) between the 2 groups (P>0.05). No significant differences in baseline mean LFM values were observed (P=0.262). However, we detected a statistically significant increase in mean LFM measurements in the BAK-preserved group (11.4 ± 5.1 ph/ms) (P=0.017) after 15 days. After 30 days, the BAK-preserved group maintained significantly higher flare values (11.9 ± 5.9 ph/ms) compared with baseline (P=0.043). On the other hand, the preservative-free group showed mean flare values of 8.4 ± 2.5 ph/ms, not significantly different from those obtained at baseline (P=1.00). We observed no statistically significant change in macular thickness measurements at days 15 and 30 in either group (P>0.05). Cystoid macular edema was not detected in this series. CONCLUSIONS Our results suggest that a short-term exposure to BAK can cause disruption of the BAB, without altering the BRB in pseudophakic eyes.
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Affiliation(s)
- Ricardo Yuji Abe
- Department of Ophthalmology, University of Campinas , Campinas, Brazil
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Pellegrini G, Rama P, Di Rocco A, Panaras A, De Luca M. Concise Review: Hurdles in a Successful Example of Limbal Stem Cell-based Regenerative Medicine. Stem Cells 2014; 32:26-34. [DOI: 10.1002/stem.1517] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Graziella Pellegrini
- Centre for Regenerative Medicine “Stefano Ferrari”; University of Modena and Reggio Emilia; Modena Italy
| | - Paolo Rama
- San Raffaele Scientific Institute, Ophthalmology Department; Milano Italy
| | - Antonio Di Rocco
- Centre for Regenerative Medicine “Stefano Ferrari”; University of Modena and Reggio Emilia; Modena Italy
| | - Athanasios Panaras
- Centre for Regenerative Medicine “Stefano Ferrari”; University of Modena and Reggio Emilia; Modena Italy
| | - Michele De Luca
- Centre for Regenerative Medicine “Stefano Ferrari”; University of Modena and Reggio Emilia; Modena Italy
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Glaucoma therapy and ocular surface disease: current literature and recommendations. Curr Opin Ophthalmol 2013; 24:136-43. [PMID: 23542350 DOI: 10.1097/icu.0b013e32835c8aba] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE OF REVIEW To provide an update on clinical and experimental literature for ocular surface effects of glaucoma therapy and to provide practical guidelines for ophthalmologists treating glaucoma patients with ocular surface disease (OSD). RECENT FINDINGS Preservatives, notably benzalkonium chloride (BAK), continue to contribute to OSD and demonstrate a variety of toxic ocular effects both in-vitro, and in animal/human studies. Recent literature frequently compares BAK with Polyquad, SofZia, and preservative-free therapies. Some clinical benefit has been demonstrated with newer BAK-free alternatives. SUMMARY BAK-free and preservative-free therapies are becoming available but are not always a feasible alternative. It is important to recognize different clinical manifestations of allergy and chronic inflammation and to discuss options for patients experiencing OSD.
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