1
|
Fineide F, Magnø M, Dahlø K, Kolko M, Heegaard S, Vehof J, Utheim TP. Topical glaucoma medications - Possible implications on the meibomian glands. Acta Ophthalmol 2024. [PMID: 38822682 DOI: 10.1111/aos.16728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 05/21/2024] [Indexed: 06/03/2024]
Abstract
One of the most common causes of blindness on a global scale is glaucoma. There is a strong association between glaucoma and increased intraocular pressure (IOP). Because of this, adequate IOP-lowering is the most important treatment strategy, mostly through topical eyedrops. Well-functioning meibomian glands are paramount for maintaining a stable tear film, and their dysfunction is the most common cause of dry eye disease. There is a growing concern that both topical glaucoma medications themselves and their added preservatives damage the meibomian glands, and consequently, the ocular surface. Preserved topical glaucoma medications appear to cause dysfunction and atrophy of the meibomian glands. Upon comparison, preserved formulations caused more symptoms of dry eye, tear film instability, inflammatory changes and meibomian gland dropout than the preservative-free counterpart. However, although seemingly less detrimental, unpreserved alternatives may diminish glandular efficacy, and, depending on the active ingredient, lead to glandular death. This negatively impacts quality of life, adherence to treatment regimens and prognosis. In this review, we explore the available evidence regarding the effects of IOP-lowering eye drops on the meibomian glands.
Collapse
Affiliation(s)
- Fredrik Fineide
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- The Norwegian Dry Eye Clinic, Oslo, Norway
- Department of Computer Science, Oslo Metropolitan University, Oslo, Norway
- SimulaMet, Oslo, Norway
| | - Morten Magnø
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
- Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
- Department of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Kristian Dahlø
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
- Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Steffen Heegaard
- Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Jelle Vehof
- Department of Twin Research & Genetic Epidemiology, King's College London, St Thomas' Hospital, London, UK
- Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
- Department of Ophthalmology, Vestfold Hospital Trust, Tønsberg, Norway
| | - Tor Paaske Utheim
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- The Norwegian Dry Eye Clinic, Oslo, Norway
- Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
- Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
- Department of Ophthalmology, Vestfold Hospital Trust, Tønsberg, Norway
- Department of Ophthalmology, Stavanger University Hospital, Oslo, Norway
- Department of Ophthalmology, Vestre Viken Hospital Trust, Drammen, Norway
- Department of Maxillofacial Surgery, Oslo University Hospital, Oslo, Norway
- Department of Research and Development, Oslo Metropolitan University, Oslo, Norway
- Department of Clinical Medicine, Faculty of Medicine, University of Bergen, Bergen, Norway
- Department of Quality and Health Technology, The Faculty of Health Sciences, University of Stavanger, Stavanger, Norway
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
- Department of Optometry, Radiography and Lighting Design, National Centre for Optics, Vision and Eye Care, Faculty of Health Sciences, University of South-Eastern Norway, Kongsberg, Norway
- Department of Health and Nursing Science, the Faculty of Health and Sport Sciences, University of Agder, Grimstad, Norway
- Department of Ophthalmology, Faculty of Life Course Sciences and Medicine, King's College London, London, UK
| |
Collapse
|
2
|
Zheng F, Su J, Wang J, Zhan Q, Su M, Ding S, Li W, Zhu YT, Guo P. Expression of ATP-Binding Cassette Transporter A1 (ABCA1) in Eyelid Tissues and Meibomian Gland Epithelial Cells. Invest Ophthalmol Vis Sci 2024; 65:24. [PMID: 38502139 PMCID: PMC10959198 DOI: 10.1167/iovs.65.3.24] [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: 11/05/2023] [Accepted: 02/27/2024] [Indexed: 03/20/2024] Open
Abstract
Purpose To validate the adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) expression and distribution in human eyelid tissues and meibomian gland epithelial cells. Methods Meibomian gland tissues from human eyelids were isolated by collagenase A digestion and cultured in defined keratinocyte serum-free medium (DKSFM). Infrared imaging was used to analyze the general morphology of meibomian glands. Hematoxylin and eosin (H&E) staining and Oil Red O staining were used to observe the morphological structure and lipid secretion in the human meibomian gland tissues. Quantitative real-time polymerase chain reaction, western blotting, and immunostaining were used to detect the mRNA and protein expression and cytolocalization of ABCA1 in the meibomian gland tissues and cultured cells. Results The degree of loss of human meibomian gland tissue was related to age. Meibomian gland lipid metabolism was also associated with age. Additionally, human meibomian gland tissues express ABCA1 mRNA and protein; glandular epithelial cells express more ABCA1 mRNA and protein than acinar cells, and their expression in acinar cells decreases with differentiation. Furthermore, the expression of ABCA1 was downregulated in abnormal meibomian gland tissues. ABCA1 was mainly localized on the cell membrane in primary human meibomian gland epithelial cells (pHMGECs), whereas it was localized in the cytoplasm of immortalized human meibomian gland epithelial cells (iHMGECs). The mRNA and protein levels of ABCA1 in pHMGECs were higher than those in iHMGECs. Conclusions Meibomian gland tissues of the human eyelid degenerate with age. ABCA1 expression in acinar cells decreases after differentiation and plays an important role in meibomian gland metabolism.
Collapse
Affiliation(s)
- Fang Zheng
- Department of Ophthalmology, Jinzhou Medical University, Jinzhou, China
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Jingjing Su
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Jiaoman Wang
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Qing Zhan
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Mei Su
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Sicheng Ding
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| | - Wei Li
- Eye Institute of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | | | - Ping Guo
- Shenzhen Eye Institute, Shenzhen Eye Hospital, Jinan University, Shenzhen, China
| |
Collapse
|
3
|
Ziemanski JF, Wilson L, Barnes S, Nichols KK. Evaluation of the effects of latanoprost and benzalkonium chloride on the cell viability and nonpolar lipid profile produced by human meibomian gland epithelial cells in culture. Mol Vis 2023; 29:289-305. [PMID: 38264609 PMCID: PMC10805331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 11/02/2023] [Indexed: 01/25/2024] Open
Abstract
Purpose The purpose of this study was to explore the effects of a PGF2α analog, latanoprost, and its preservative, benzalkonium chloride (BAK), on the cell viability and lipidomic expression of immortalized human meibomian gland epithelial cells (HMGECs). Methods Differentiated HMGECs were exposed to latanoprost (0.05 to 50 µg/ml), BAK (0.2 to 200 µg/ml), or combined latanoprost-BAK (0.05-0.2 to 50-200 µg/ml). EP- and FP-type receptors, the cognate receptors of PGE2 and PGF2α, were inhibited, thereby sparing and isolating the function of each receptor to one condition. Cell viability was assessed by ATP quantitation, and lipid extracts were analyzed by ESI-MSMSALL with a Triple TOF 5600 Mass Spectrometer (SCIEX, Framingham, MA) using SCIEX LipidView 1.3. Results Latanoprost and BAK were found to be lethal to HMGECs at the highest concentrations (p < 0.001 for both). The cytotoxicity of latanoprost was mediated through FP- and EP-independent mechanisms. Both latanoprost and BAK significantly modulated the lipidomic expression of several cholesteryl esters (8% and 30%, respectively) and triacylglycerols (10% and 12%, respectively). The combined latanoprost-BAK agent appeared to be no more toxic and to only negligibly alter the lipid profile relative to its individual components. Conclusions The use of latanoprost and BAK in glaucoma may alter the viability of the meibomian glands and their lipid expression in vivo. Sublethal concentrations of BAK appear to modulate meibum lipid expression, particularly in relation to sterol biosynthesis. Non-preserved latanoprost had less cytotoxicity at lower doses and fewer lipidomic effects compared to BAK, further strengthening the argument in favor of BAK-free pharmaceutical preparations.
Collapse
Affiliation(s)
- Jillian F. Ziemanski
- University of Alabama at Birmingham School of Optometry Department of Optometry and Vision Science Birmingham, AL
| | - Landon Wilson
- University of Alabama at Birmingham School of Medicine Department of Pharmacology and Toxicology Birmingham, AL
| | - Stephen Barnes
- University of Alabama at Birmingham School of Medicine Department of Pharmacology and Toxicology Birmingham, AL
| | - Kelly K. Nichols
- University of Alabama at Birmingham School of Optometry Department of Optometry and Vision Science Birmingham, AL
| |
Collapse
|
4
|
Sullivan DA, da Costa AX, Del Duca E, Doll T, Grupcheva CN, Lazreg S, Liu SH, McGee SR, Murthy R, Narang P, Ng A, Nistico S, O'Dell L, Roos J, Shen J, Markoulli M. TFOS Lifestyle: Impact of cosmetics on the ocular surface. Ocul Surf 2023; 29:77-130. [PMID: 37061220 PMCID: PMC11246752 DOI: 10.1016/j.jtos.2023.04.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/17/2023]
Abstract
In this report the use of eye cosmetic products and procedures and how this represents a lifestyle challenge that may exacerbate or promote the development of ocular surface and adnexal disease is discussed. Multiple aspects of eye cosmetics are addressed, including their history and market value, psychological and social impacts, possible problems associated with cosmetic ingredients, products, and procedures, and regulations for eye cosmetic use. In addition, a systematic review that critically appraises randomized controlled trial evidence concerning the ocular effects of eyelash growth products is included. The findings of this systematic review highlight the evidence gaps and indicate future directions for research to focus on ocular surface outcomes associated with eyelash growth products.
Collapse
Affiliation(s)
| | | | - Ester Del Duca
- Icahn School of Medicine at Mount Sinai, New York City, NY, USA
| | | | | | - Sihem Lazreg
- Lazreg Cornea and Ocular Surface Center, Blida, Algeria
| | - Su-Hsun Liu
- University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | | | | | | | - Alison Ng
- Centre for Ocular Research & Education, School of Optometry and Vision Science, University of Waterloo, Waterloo, Canada
| | - Steven Nistico
- Department of Dermatology, University Magna Graecia, Catanzaro, Italy
| | | | | | - Joanne Shen
- Department of Ophthalmology, Mayo Clinic in Arizona, Scottsdale, AZ, USA
| | - Maria Markoulli
- School of Optometry and Vision Science, UNSW Sydney, NSW, Australia
| |
Collapse
|
5
|
Kolko M, Gazzard G, Baudouin C, Beier S, Brignole-Baudouin F, Cvenkel B, Fineide F, Hedengran A, Hommer A, Jespersen E, Messmer EM, Murthy R, Sullivan AG, Tatham AJ, Utheim TP, Vittrup M, Sullivan DA. Impact of glaucoma medications on the ocular surface and how ocular surface disease can influence glaucoma treatment. Ocul Surf 2023; 29:456-468. [PMID: 37302545 DOI: 10.1016/j.jtos.2023.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/13/2023]
Affiliation(s)
- Miriam Kolko
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Gus Gazzard
- Glaucoma Service, Moorfields Eye Hospital NHS Foundation Trust, London, UK; UCL Institute of Ophthalmology, London, UK; NIHR-Moorfields Biomedical Research Centre, London, UK
| | - Christophe Baudouin
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; Université Paris-Saclay, Versailles-Saint-Quentin-en-Yvelines, Paris, France; Institut de la Vision, Sorbonne Université, Paris, France
| | - Sofie Beier
- Royal Danish Academy - Architecture, Design, Conservation, Copenhagen, Denmark
| | - Françoise Brignole-Baudouin
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; Institut de la Vision, Sorbonne Université, Paris, France; Faculté de Pharmacie, Paris Cité université, Paris, France
| | - Barbara Cvenkel
- Department of Ophthalmology, University Medical Centre Ljubljana, Ljubljana, Slovenia; Medical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Fredrik Fineide
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
| | - Anne Hedengran
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark; Department of Ophthalmology, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
| | - Anton Hommer
- Department of Ophthalmology, HERA Hospital, Vienna, Austria
| | | | | | | | | | - Andrew J Tatham
- Princess Alexandra Eye Pavilion and Department of Ophthalmology, University of Edinburgh, Edinburgh, UK
| | - Tor Paaske Utheim
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
| | | | | |
Collapse
|
6
|
Du YL, Peng X, Liu Y, Wang JS, Ye YF, Xu KK, Qu JY, Chen H, Xie HT, Zhang MC. Ductal Hyperkeratinization and Acinar Renewal Abnormality: New Concepts on Pathogenesis of Meibomian Gland Dysfunction. Curr Issues Mol Biol 2023; 45:1889-1901. [PMID: 36975492 PMCID: PMC10047716 DOI: 10.3390/cimb45030122] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/18/2023] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
Meibomian gland dysfunction (MGD) is a functional and morphological disorder of the meibomian glands which results in qualitative or quantitative alteration in meibum secretion and is the major cause of evaporative dry eye (EDE). EDE is often characterized by tear film instability, increased evaporation, hyperosmolarity, inflammation, and ocular surface disorder. The precise pathogenesis of MGD remains elusive. It has been widely considered that MGD develops as a result of ductal epithelial hyperkeratinization, which obstructs the meibomian orifice, halts meibum secretion, and causes secondary acinar atrophy and gland dropout. Abnormal self-renewal and differentiation of the acinar cells also play a significant role in MGD. This review summarizes the latest research findings regarding the possible pathogenesis of MGD and provides further treatment strategies for MGD-EDE patients.
Collapse
Affiliation(s)
- Ya-Li Du
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xi Peng
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yang Liu
- Department of Ophthalmology, Zhongnan Hospital of Wuhan University, Wuhan 430071, China
| | - Jia-Song Wang
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - You-Fan Ye
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Kang-Kang Xu
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jing-Yu Qu
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Hua Chen
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Hua-Tao Xie
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Ming-Chang Zhang
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| |
Collapse
|
7
|
Ziemanski JF, Wilson L, Barnes S, Nichols KK. Prostaglandin E2 and F2α Alter Expression of Select Cholesteryl Esters and Triacylglycerols Produced by Human Meibomian Gland Epithelial Cells. Cornea 2022; 41:95-105. [PMID: 34483274 PMCID: PMC8648972 DOI: 10.1097/ico.0000000000002835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 06/10/2021] [Indexed: 01/03/2023]
Abstract
PURPOSE PGF2α analogs are commonly used to treat glaucoma and are associated with higher rates of meibomian gland dysfunction (MGD). The purpose of this study was to evaluate the physiological effects of PGF2α and PGE2 on immortalized human meibomian gland epithelial cells (HMGECs). METHODS HMGECs were immunostained for the 4 PGE2 receptors (EP1, EP2, EP3, and EP4) and 1 PGF2α receptor (FP) and imaged. Rosiglitazone-differentiated HMGECs were exposed to PGF2α and PGE2 (10-9 to 10-6 M) for 3 hours. Cell viability was assessed by an adenosine triphosphate-based luminescent assay, and lipid extracts were analyzed for cholesteryl esters (CEs), wax esters (WEs), and triacylglycerols (TAGs) by ESI-MSMSALL in positive ion mode by a Triple TOF 5600 Mass Spectrometer using SCIEX LipidView 1.3. RESULTS HMGECs expressed 3 PGE2 receptors (EP1, EP2, and EP4) and the 1 PGF2α receptor (FP). Neither PGE2 nor PGF2α showed signs of cytotoxicity at any of the concentrations tested. WEs were not detected from any of the samples, but both CEs and TAGs exhibited a diverse and dynamic profile. PGE2 suppressed select CEs (CE 22:1, CE 26:0, CE 28:1, and CE 30:1). PGF2α dose dependently increased several CEs (CE 20:2, CE 20:1, CE 22:1, and CE 24:0) yet decreased others. Both prostaglandins led to nonspecific TAG remodeling. CONCLUSIONS PGE2 and PGF2α showed minimal effect on HMGEC viability. PGF2α influences lipid expression greater than PGE2 and may do so by interfering with meibocyte differentiation. This work may provide insight into the mechanism of MGD development in patients with glaucoma treated with PGF2α analogs.
Collapse
Affiliation(s)
- Jillian F. Ziemanski
- University of Alabama at Birmingham, School of Optometry, Department of Optometry Vision Science, Birmingham, AL, USA
| | - Landon Wilson
- University of Alabama at Birmingham, School of Medicine, Department of Pharmacology Toxicology, Birmingham, AL, USA
| | - Stephen Barnes
- University of Alabama at Birmingham, School of Medicine, Department of Pharmacology Toxicology, Birmingham, AL, USA
| | - Kelly K. Nichols
- University of Alabama at Birmingham, School of Optometry, Department of Optometry Vision Science, Birmingham, AL, USA
| |
Collapse
|
8
|
Expression of Acyl-CoA wax-alcohol acyltransferase 2 (AWAT2) by human and rabbit meibomian glands and meibocytes. Ocul Surf 2021; 23:60-70. [PMID: 34838721 PMCID: PMC10393063 DOI: 10.1016/j.jtos.2021.11.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 11/18/2021] [Accepted: 11/20/2021] [Indexed: 11/22/2022]
Abstract
PURPOSE Previously, we showed that Acyl-CoA wax-alcohol acyltransferase 2 (AWAT2), an essential enzyme required for meibum wax ester synthesis, was not expressed by immortalized human meibomian gland epithelial cells (hMGEC) in culture. To begin to understand the mechanisms controlling AWAT2 expression, we have analyzed its expression in human and rabbit meibomian glands and cultured meibocytes. METHODS Rabbit meibocyte progenitor cells (rMPC) were first grown in Cnt-BM.1 basal medium (Cellntec) supplemented with rhEGF, FGF10, and ROCK inhibitor (Y-27632 dihydrochloride), and then passed at 70-80% confluency with Accutase. Differentiation of rMPC to meibocytes (rMC) was induced by removal of Y-27632 and addition of 1 mM calcium with and without PPARγ agonists. RNA from the tissue, primary, passaged rMPC and differentiated rMC were obtained for AWAT2 qPCR analysis. Proteins and cells were evaluated for western blotting and neutral lipid synthesis, respectively. For comparison, human meibomian glands were separated for RNA and protein analysis. hMGEC was cultured to collect RNA and protein. RESULTS Rabbit rMPCs were successfully grown, passaged, and differentiated, showing a significant increase in lipid droplet accumulation. AWAT2 RNA was highly expressed in tissue but showed a -16.9 log2 fold decrease in primary and passaged rMPCs and was not induced by differentiation to rMC. By comparison, human meibomian glands showed high expression of AWAT2, and hMGEC expressed non-detectable levels of AWAT2 transcripts or protein. CONCLUSIONS AWAT2 expression is lost in cultured rMPC and rMC suggesting that cells in culture do not undergo complete meibocyte differentiation and require yet to be identified culture conditions.
Collapse
|
9
|
Qu JY, Xiao YT, Zhang YY, Xie HT, Zhang MC. Hedgehog Signaling Pathway Regulates the Proliferation and Differentiation of Rat Meibomian Gland Epithelial Cells. Invest Ophthalmol Vis Sci 2021; 62:33. [PMID: 33616621 PMCID: PMC7910630 DOI: 10.1167/iovs.62.2.33] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Purpose Meibomian glands play a vital role in maintaining ocular surface stability. This study aimed to investigate whether Hedgehog signaling is involved in the regulation of meibomian gland epithelial cells. Methods Rat meibomian glands epithelial cells (RMGECs) were isolated from ducts and ductules, and then were cultivated to passage two on Matrigel coated wells in meibomian gland epithelial cells medium (MGECM). Cells were switched from MGECM to differentiation medium (DM) or DM added 10 µg/mL azithromycin (DM + AZM) when reached 50% to 60% confluence. The effects of the Smoothened (Smo) agonist (Smo agonist [SAG]) and antagonist (by cyclopamine) on RMGECs were analyzed using quantitative RT-PCR, cell proliferation analysis, immunofluorescence staining, and Nile red staining. Results The Hedgehog receptor, Smo, and its downstream molecules, Glis, were expressed both in vivo and in vitro. Smo and Gli1 both decreased with the increase of differentiation in vitro. Smo antagonist, cyclopamine, reduced cell numbers, and the expression of Ki67 in MGECM, and promoted the expression of SREBP1 and lipid production in DM + AZM. Smo agonist, SAG, inhibited the expression of SREBP1 and lipid accumulation in DM + AZM but showed no significant effects on raising cell numbers and the expression of Ki67 in MGECM. Conclusions The Hedgehog signaling pathway appears to play important roles in RMGECs proliferation and differentiation. This may provide a potential therapeutic way to treat meibomian gland dysfunction (MGD).
Collapse
Affiliation(s)
- Jing-Yu Qu
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu-Ting Xiao
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ying-Ying Zhang
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hua-Tao Xie
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ming-Chang Zhang
- Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
10
|
Endo KI, Sakamoto A, Fujisawa K. Diquafosol tetrasodium elicits total cholesterol release from rabbit meibomian gland cells via P2Y 2 purinergic receptor signalling. Sci Rep 2021; 11:6989. [PMID: 33772064 DOI: 10.1038/s41598-021-86433-66989] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 03/15/2021] [Indexed: 05/25/2023] Open
Abstract
Diquafosol tetrasodium (DQS), a purinergic P2Y2 receptor agonist, stimulates secretion of both water and mucins from the conjunctiva into tears. Hence, DQS-containing eye drops have been approved as a therapeutic option for dry eye disease in some Asian countries, including Japan. Recent clinical reports state that instilling DQS-containing eye drops significantly increases the lipid layer thickness in tears. Therefore, we examined this compound's direct actions on holocrine lipid-secreting meibomian gland cells and their function. Isolated meibomian gland cells (meibocytes) were procured from rabbits and cultivated in serum-free culture medium. Differentiated meibocytes with pioglitazone were used for the subsequent experiments. Intracellular Ca2+ signalling of the cells was dramatically elevated with DQS addition in a dose-dependent manner. This DQS-induced elevation was almost completely cancelled by the coexistence of the selective P2Y2 receptor antagonist AR-C118925XX. DQS treatment also facilitated total cholesterol (TC) release from cells into the medium. This effect of DQS on TC was suppressed significantly by the intracellular Ca2+ chelator BAPTA-AM as well as by AR-C118925XX. DNA fragmentation analysis revealed that DQS may have enhanced the apoptotic DNA fragmentation caused spontaneously by cells. Thus, DQS could stimulate meibocytes to release lipids through the P2Y2 receptor and possibly facilitate holocrine cell maturation.
Collapse
Affiliation(s)
- Ken-Ichi Endo
- Pharmaceutics and Pharmacology, Research and Development Division, Santen Pharmaceutical Co., Ltd., 8916-16 Takayama-cho, Ikoma, Nara, 630-0101, Japan.
| | - Asuka Sakamoto
- Pharmaceutics and Pharmacology, Research and Development Division, Santen Pharmaceutical Co., Ltd., 8916-16 Takayama-cho, Ikoma, Nara, 630-0101, Japan
| | - Koushi Fujisawa
- Pharmaceutics and Pharmacology, Research and Development Division, Santen Pharmaceutical Co., Ltd., 8916-16 Takayama-cho, Ikoma, Nara, 630-0101, Japan
| |
Collapse
|
11
|
Diquafosol tetrasodium elicits total cholesterol release from rabbit meibomian gland cells via P2Y 2 purinergic receptor signalling. Sci Rep 2021; 11:6989. [PMID: 33772064 PMCID: PMC7997929 DOI: 10.1038/s41598-021-86433-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 03/15/2021] [Indexed: 11/21/2022] Open
Abstract
Diquafosol tetrasodium (DQS), a purinergic P2Y2 receptor agonist, stimulates secretion of both water and mucins from the conjunctiva into tears. Hence, DQS-containing eye drops have been approved as a therapeutic option for dry eye disease in some Asian countries, including Japan. Recent clinical reports state that instilling DQS-containing eye drops significantly increases the lipid layer thickness in tears. Therefore, we examined this compound’s direct actions on holocrine lipid-secreting meibomian gland cells and their function. Isolated meibomian gland cells (meibocytes) were procured from rabbits and cultivated in serum-free culture medium. Differentiated meibocytes with pioglitazone were used for the subsequent experiments. Intracellular Ca2+ signalling of the cells was dramatically elevated with DQS addition in a dose-dependent manner. This DQS-induced elevation was almost completely cancelled by the coexistence of the selective P2Y2 receptor antagonist AR-C118925XX. DQS treatment also facilitated total cholesterol (TC) release from cells into the medium. This effect of DQS on TC was suppressed significantly by the intracellular Ca2+ chelator BAPTA-AM as well as by AR-C118925XX. DNA fragmentation analysis revealed that DQS may have enhanced the apoptotic DNA fragmentation caused spontaneously by cells. Thus, DQS could stimulate meibocytes to release lipids through the P2Y2 receptor and possibly facilitate holocrine cell maturation.
Collapse
|
12
|
Han X, Yang S, Kam WR, Sullivan DA, Liu Y. The Carbonic Anhydrase Inhibitor Dorzolamide Stimulates the Differentiation of Human Meibomian Gland Epithelial Cells. Curr Eye Res 2020; 45:1604-1610. [PMID: 32434386 DOI: 10.1080/02713683.2020.1772832] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE Clinical studies have indicated that the long-term use of topical antiglaucoma drugs, such as carbonic anhydrase inhibitors (CAIs), may lead to meibomian gland dysfunction (MGD). We hypothesize that these adverse effects involve a direct influence on human MG epithelial cells (HMGECs). The purpose our present investigation was to test our hypothesis and determine whether exposure to dorzolamide, a CAI, impacts the proliferation, intracellular signaling and differentiation of HMGECs. MATERIALS AND METHODS We cultured immortalized (i) HMGECs with vehicle or various concentrations of dorzolamide for 6 days. Cells were enumerated with a hemocytometer, and examined for their morphology, Akt signaling activity, accumulation of neutral lipids, phospholipids and lysosomes, and the expression of protein biomarkers for lipogenesis regulation, lysosomes and autophagosomes. RESULTS Our results show that a high, 500 µg/ml concentration of dorzolamide causes a significant decrease in Akt signaling and the proliferation of iHMGECs. However, the high dose of dorzolamide also promotes the differentiation of iHMGECs. This response features increases in the number of lysosomes, the accumulation of phospholipids, and the expression of the light chain 3A biomarker for autophagosomes. In contrast, the therapeutic amount (50 µg/ml) of dorzolamide has no impact on the proliferative or differentiative abilities of iHMGECs. CONCLUSIONS Our results support our hypothesis and demonstrate that the CAI dorzolamide does exert a direct influence on the proliferation and differentiation of iHMGECs. However, this effect is elicited only by a high, and not a therapeutic, amount of dorzolamide. Abbreviations: AKT: phosphoinositide 3-kinase-protein kinase B; BPE: bovine pituitary extract; CAD: cationic amphiphilic drug; DED: dry eye disease; DMEM/F12: 1:1 mixture of Dulbecco's modified Eagle's medium and Ham's F-12; EGF: epidermal growth factor; FBS: fetal bovine serum; iHMGECs: immortalized human meibomian gland epithelial cells; KSFM: keratinocyte serum-free medium; LAMP-1: lysosomal-associated membrane protein 1; LC3A: light chain 3A; MGD: meibomian gland dysfunction; SREBP-1: sterol regulatory element-binding protein 1.
Collapse
Affiliation(s)
- Xi Han
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School , Boston, Massachusetts, USA.,Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, China
| | - Shan Yang
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School , Boston, Massachusetts, USA.,Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College , Beijing, China
| | - Wendy R Kam
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School , Boston, Massachusetts, USA
| | - David A Sullivan
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School , Boston, Massachusetts, USA
| | - Yang Liu
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School , Boston, Massachusetts, USA
| |
Collapse
|
13
|
Eicosapentaenoic acid (EPA) activates PPARγ signaling leading to cell cycle exit, lipid accumulation, and autophagy in human meibomian gland epithelial cells (hMGEC). Ocul Surf 2020; 18:427-437. [PMID: 32360782 DOI: 10.1016/j.jtos.2020.04.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 04/21/2020] [Accepted: 04/23/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE The purpose of this study was to access the ability of the natural PPAR agonist, eicosapentaenoic acid (EPA), to activate PPAR gamma (γ) signaling leading to meibocyte differentiation in human meibomian gland epithelial cell (hMGEC). METHODS HMGEC were exposed to EPA, alone and in combination with the specific PPARγ antagonist, T0070907, to selectively block PPARγ signaling. Expression of PPARγ response genes were evaluated by qPCR. Effect on cell cycle was evaluated using Ki-67 labelling and western blots. During differentiation, autophagy was monitored using the Autophagy Tandem Sensor (ATS) and LysoTracker. Lipid accumulation was characterized by Stimulated Raman Scattering microscopy (SRS) and neutral lipid staining in combination with ER-Tracker, LysoTracker, and ATS. Autophagy was also investigated using western blotting. Seahorse XF analysis was performed to monitor mitochondrial function. RESULTS EPA specifically upregulated expression of genes related to lipid synthesis and induced cell cycle exit through reduced cyclin D1 expression and increased p21 and p27 expression. EPA also induced accumulation of lipid droplets in a time and dose dependent manner (P < 0.05) by specific PPARγ signaling. Lipid analysis identified both de novo synthesis and extracellular transport of lipid to form lipid droplets that were localized to the ER. PPARγ signaling also induced activation of AMPK-ULK1 signaling and autophagy, while inhibition of autophagy induced mitochondrial crisis with no effect on lipid accumulation. CONCLUSIONS EPA induces meibocyte differentiation through PPARγ activation that is characterized by cell cycle exit, de novo and transported lipid accumulation in the ER, and autophagy.
Collapse
|
14
|
Fukuoka S, Arita R. Tear film lipid layer increase after diquafosol instillation in dry eye patients with meibomian gland dysfunction: a randomized clinical study. Sci Rep 2019; 9:9091. [PMID: 31235821 PMCID: PMC6591396 DOI: 10.1038/s41598-019-45475-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 05/14/2019] [Indexed: 12/13/2022] Open
Abstract
Diquafosol promotes secretion of tear fluid and mucin at the ocular surface and is administered for treatment of dry eye (DE). Tear film lipid layer is secreted from meibomian glands and stabilizes the tear film. We recently showed that diquafosol administration increased lipid layer thickness (LLT) for up to 60 min in normal human eyes. We here evaluated tear film lipid layer in DE patients (n = 47) with meibomian gland dysfunction (MGD) before as well as 30, 60, and 90 min after diquafosol administration. One drop of artificial tears or one drop of diquafosol was applied randomly to the eyes of each patient. Diquafosol significantly increased LLT at 30 (P < 0.001) and 60 (P = 0.042) min and noninvasive tear film breakup time for at least 90 min (P < 0.001 at each assessment point). Artificial tears had no such effect. Diquafosol significantly improved the tear interferometric pattern compared with artificial tears (P < 0.001 at each assessment point). A single topical administration of diquafosol thus improved LLT and tear film stability in DE patients with MGD, suggesting that diquafosol is a potential treatment not only for aqueous-deficient DE but also for evaporative DE associated with MGD.
Collapse
Affiliation(s)
- Shima Fukuoka
- Omiya Hamada Eye Clinic, 1-169-1 Sakuragicho, Omiya-ku, Saitama, Saitama, 330-0854, Japan.,Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.,Lid and Meibomian Gland Working Group (LIME), 626-11 Minami-Nakano, Minuma-ku, Saitama, Saitama, 337-0042, Japan
| | - Reiko Arita
- Itoh Clinic, 626-11 Minami-Nakano, Minuma-ku, Saitama, Saitama, 337-0042, Japan. .,Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. .,Lid and Meibomian Gland Working Group (LIME), 626-11 Minami-Nakano, Minuma-ku, Saitama, Saitama, 337-0042, Japan.
| |
Collapse
|
15
|
Amano S. Meibomian Gland Dysfunction: Recent Progress Worldwide and in Japan. Invest Ophthalmol Vis Sci 2019; 59:DES87-DES93. [PMID: 30481811 DOI: 10.1167/iovs.17-23553] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
In this review, the importance of Japanese research on meibomian gland dysfunction (MGD) is discussed from the perspective of global academic and clinical research on this topic. Many Japanese physicians and researchers have contributed to recent worldwide progress in various fields of MGD research, including pathophysiology, epidemiology, diagnosis, and therapy. In Japan, recent studies in the field of pathophysiology have provided direct evidence for the hypothesis that lipid composition and reactive oxygen species play a crucial role in the development and worsening of MGD. In the field of diagnosis, slit-lamp examination, in vivo confocal microscopy, and meibography have been widely used in studies from Japan. On the basis of the results of these studies, the MGD working group in Japan has proposed new diagnostic criteria for obstructive MGD. According to these criteria, obstructive MGD is considered present when ocular symptoms, anatomic abnormalities, and meibomian gland obstruction are present. In the field of therapy, devices and drugs newly developed in Japan have been shown to enhance the efficacy of lid hygiene and warm compression. Moreover, diquafosol and vitamin D3 have been shown to be effective for MGD. In conclusion, standardization of the diagnosis and treatment of MGD is necessary to enable all patients with MGD to receive appropriate treatment, and specific diagnostic criteria with cutoff values for each parameter are necessary to standardize the diagnosis of MGD.
Collapse
|
16
|
Rath A, Eichhorn M, Träger K, Paulsen F, Hampel U. In vitro effects of benzalkonium chloride and prostaglandins on human meibomian gland epithelial cells. Ann Anat 2018; 222:129-138. [PMID: 30580056 DOI: 10.1016/j.aanat.2018.12.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/04/2018] [Accepted: 12/11/2018] [Indexed: 01/17/2023]
Abstract
PURPOSE Benzalkonium chloride is the most widely used preservative in ophthalmic topical solutions. The aim of this study was to investigate the influence of BAC as a single substance or as a component of several commercially available ophthalmic solutions on meibomian gland epithelial cells in vitro. MATERIALS AND METHODS An immortalized human meibomian gland epithelial cell line (HMGEC) was used and cells were cultured in the absence or presence of fetal bovine serum to assess cell morphology, cell proliferation, cell viability (MTS assay) and impedance sensing (ECIS) after stimulation with BAC. Further, the viability of HMGECs stimulated with BAC-containing and BAC-free bimatoprost, travoprost and latanoprost was evaluated using the MTS assay. Real-time PCR analysis for hyperkeratinization associated genes (cornulin, involucrin) was performed. RESULTS In the absence of serum, the proliferation rate of HMGECs decreased starting with 0.1μg/ml BAC. At concentrations of 50μg/ml BAC and higher, cell viability was reduced after 10min exposure with a corresponding change in cell morphology. Toxicity of BAC-containing ophthalmic solutions was greater than that of BAC alone, whereas BAC-free alternative products did not significantly influence cell viability. Confluence, cell-cell contacts and serum-containing medium appeared to facilitate HMGECs survival. Expression rate of involucrin and cornulin declined after exposure to preserved bimatoprost and BAC. CONCLUSIONS BAC showed cytotoxic effects on HMGECs starting with a concentration of 0.1μg/ml. The combination of BAC and prostaglandin-analogs might have a synergistic effect which results in higher toxicity than BAC alone. Unpreserved eye drops and eye drops preserved with Polyquaternium-1 are less damaging to HMGECs.
Collapse
Affiliation(s)
- Anca Rath
- Department of Anatomy II, Friedrich Alexander University of Erlangen-Nürnberg, Universitätsstraße 19, Erlangen, Germany.
| | - Michael Eichhorn
- Department of Anatomy II, Friedrich Alexander University of Erlangen-Nürnberg, Universitätsstraße 19, Erlangen, Germany.
| | - Katharina Träger
- Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstr. 1, Mainz, Germany.
| | - Friedrich Paulsen
- Department of Anatomy II, Friedrich Alexander University of Erlangen-Nürnberg, Universitätsstraße 19, Erlangen, Germany.
| | - Ulrike Hampel
- Department of Anatomy II, Friedrich Alexander University of Erlangen-Nürnberg, Universitätsstraße 19, Erlangen, Germany; Department of Ophthalmology, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstr. 1, Mainz, Germany.
| |
Collapse
|
17
|
Liu Y, Chen D, Chen X, Kam WR, Hatton MP, Sullivan DA. Hypoxia: A breath of fresh air for the meibomian gland. Ocul Surf 2018; 17:310-317. [PMID: 30528291 DOI: 10.1016/j.jtos.2018.12.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 12/19/2022]
Abstract
PURPOSE Optimal meibomian gland (MG) function is critically important for the health and wellbeing of the ocular surface. We hypothesize that low oxygen (O2) conditions promote the function of human MG epithelial cells (HMGECs) and that human MGs exist in a relatively hypoxic environment. The purpose of this study was to test our hypotheses. METHODS We used human and mouse eyelid segments, and immortalized human MG epithelial cells (IHMGECs) in our studies. To evaluate oxygen (O2) levels in the mouse MG and vicinity, we injected pimonidazole (pimo), a hypoxia marker, before sacrifice. Human eyelid samples were stained with the hypoxia marker glucose transporter 1 (Glut-1). To determine the effect of low O2 levels on IHMGECs, we cultured cells under proliferating and differentiating conditions in both normoxic (21% O2) and hypoxic (3% O2) conditions for 5-15 days. IHMGECs were evaluated for cell number, neutral lipid content, lysosome accumulation, expression of biomarker proteins and DNase II activity. RESULTS Our results demonstrate that human and mouse MGs, but not the surrounding connective tissue, exist in a relatively hypoxic environment in vivo. In addition, our findings show that hypoxia does not influence IHMGEC numbers in basal or proliferating culture conditions, but does stimulate the expression of SREBP-1 in differentiating IHMGECs. Hypoxia also significantly increased DNase II activity, and apparently IHMGEC terminal differentiation. CONCLUSIONS Our Results support our hypotheses, and indicate that relative hypoxia promotes MG function.
Collapse
Affiliation(s)
- Yang Liu
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA.
| | - Di Chen
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA; Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, 100730, China
| | - Xiaomin Chen
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA; Zhongnan Hospital, Wuhan University, Wuhan, China
| | - Wendy R Kam
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA
| | - Mark P Hatton
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA; Ophthalmic Consultants of Boston, Boston, 02114, USA
| | - David A Sullivan
- Schepens Eye Research Institute, Massachusetts Eye and Ear, and Department of Ophthalmology, Harvard Medical School, Boston, 02114, USA
| |
Collapse
|
18
|
Abstract
PURPOSE Investigators have discovered that topical antiglaucoma drugs may induce meibomian gland dysfunction. This response may contribute to the dry eye disease commonly found in patients with glaucoma taking such medications. We hypothesize that drug action involves a direct effect on human meibomian gland epithelial cells (HMGECs). To test this hypothesis, we examined the influence of the antiglaucoma drugs, pilocarpine and timolol, on the morphology, survival, proliferation, and differentiation of HMGECs. METHODS Immortalized (I) HMGECs (n = 2-3 wells/treatment/experiment) were cultured with multiple concentrations of pilocarpine or timolol for up to 7 days. Experiments included positive controls for proliferation (epidermal growth factor and bovine pituitary extract) and differentiation (azithromycin). Cells were enumerated using a hemocytometer and evaluated for morphology, neutral lipid staining, and lysosome accumulation. RESULTS Our results demonstrate that pilocarpine and timolol cause a dose-dependent decrease in the survival of IHMGECs. The clinically used concentrations are toxic and lead to cell atrophy, poor adherence, or death. By contrast, drug levels that are known to accumulate within the conjunctiva, adjacent to the meibomian glands, do not influence IHMGEC survival. These latter concentrations also have no effect on IHMGEC proliferation or differentiation, and they do not interfere with the ability of azithromycin to stimulate cellular neutral lipid and lysosome accumulation. This dose of pilocarpine, though, did suppress the epidermal growth factor+bovine pituitary extract-induced proliferation of IHMGECs. CONCLUSIONS Our results support our hypothesis and demonstrate that these antiglaucoma drugs, pilocarpine and timolol, have direct effects on HMGECs that may influence their morphology, survival, and proliferative capacity.
Collapse
|
19
|
The human meibomian gland epithelial cell line as a model to study meibomian gland dysfunction. Exp Eye Res 2017; 163:46-52. [DOI: 10.1016/j.exer.2017.03.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/17/2017] [Accepted: 03/23/2017] [Indexed: 01/05/2023]
|
20
|
Abstract
Meibum is a lipid-rich secretion that is produced by fully differentiated meibocytes in the holocrine Meibomian glands (MG) of humans and most mammals. The secretion is a part of a defense mechanism that protects the ocular surface from hazardous environmental factors, and from desiccation. Meibomian lipids that have been identified in meibum are very diverse and unique in nature. The lipid composition of meibum is different from virtually any other lipid pool found in the human body. In fact, meibum is quite different from sebum, which is the closest secretion that is produced by anatomically, physiologically, and biochemically related sebaceous glands. However, meibum of mice have been shown to closely resemble that of humans, implying similar biosynthetic mechanisms in MG of both species. By analyzing available genomic, immunohistochemical, and lipidomic data, we have envisioned a unifying network of enzymatic reactions that are responsible for biosynthesis of meibum, which we call meibogenesis. Our current theory is based on an assumption that most of the biosynthetic reactions of meibogenesis are catalyzed by known enzymes. However, the main features that make meibum unique - the ratio of identified classes of lipids, the extreme length of its components, extensive ω-hydroxylation of fatty acids and alcohols, iso- and anteiso-branching of meibomian lipids (e.g. waxes), and the presence of rather unique complex lipids with several ester bonds - make it possible that either the activity of known enzymes is altered in MG, or some unknown enzymes contribute to the processes of meibogenesis, or both. Studies are in progress to elucidate meibogenesis on molecular level.
Collapse
Affiliation(s)
- Igor A Butovich
- Department of Ophthalmology and the Graduate School of Biomedical Sciences, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9057, United States.
| |
Collapse
|
21
|
Amano S, Inoue K. Effect of topical 3% diquafosol sodium on eyes with dry eye disease and meibomian gland dysfunction. Clin Ophthalmol 2017; 11:1677-1682. [PMID: 29075094 PMCID: PMC5608477 DOI: 10.2147/opth.s148167] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Purpose To prospectively evaluate the effect of topical diquafosol sodium on eyes with dry eye disease (DED) and meibomian gland dysfunction (MGD). Patients and methods The subjects were consecutive patients diagnosed with both DED and MGD at Inouye Eye Hospital between March and September of 2016. The subjects were administered topical 3% diquafosol sodium ophthalmic solution six times a day for 3 months. At each study visit, subjects underwent slit-lamp examination and completed MGD symptoms and dry eye-related quality of life score (DEQS) questionnaires. Meibum quality (meibum score) and meibomian gland loss (meiboscore) were evaluated. Tear lipid layer thickness was measured in both eyes with an ocular surface interferometer immediately after clinic arrival and 20 minutes after instillation of one drop of topical diquafosol. Results Thirteen patients (3 men, 10 women) with a mean age of 69.5±8.3 years completed the 3-month study. The number of telangiectasia and plugged meibomian gland orifices significantly decreased from baseline after 1 month of diquafosol use. The meibum score and the meiboscore significantly decreased from baseline at 3 months. Also, the lipid layer thickness was greater after diquafosol administration than before administration at baseline and 1, 2, and 3 months by 12.2, 11.5, 9.5, and 17.0 nm, respectively, but this difference was only significant at 3 months (p=0.039). The DEQS ocular symptom (p=0.065) and MGD questionnaire (p=0.081) scores tended to be lower than baseline at 3 months. Conclusion Diquafosol sodium ophthalmic solution improves DED- and MGD-related signs in eyes with MGD.
Collapse
Affiliation(s)
- Shiro Amano
- Inouye Eye Hospital, Chiyoda-ku, Tokyo, Japan
| | - Kenji Inoue
- Inouye Eye Hospital, Chiyoda-ku, Tokyo, Japan
| |
Collapse
|
22
|
Bron AJ, de Paiva CS, Chauhan SK, Bonini S, Gabison EE, Jain S, Knop E, Markoulli M, Ogawa Y, Perez V, Uchino Y, Yokoi N, Zoukhri D, Sullivan DA. TFOS DEWS II pathophysiology report. Ocul Surf 2017; 15:438-510. [PMID: 28736340 DOI: 10.1016/j.jtos.2017.05.011] [Citation(s) in RCA: 975] [Impact Index Per Article: 139.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 05/26/2017] [Indexed: 12/18/2022]
Abstract
The TFOS DEWS II Pathophysiology Subcommittee reviewed the mechanisms involved in the initiation and perpetuation of dry eye disease. Its central mechanism is evaporative water loss leading to hyperosmolar tissue damage. Research in human disease and in animal models has shown that this, either directly or by inducing inflammation, causes a loss of both epithelial and goblet cells. The consequent decrease in surface wettability leads to early tear film breakup and amplifies hyperosmolarity via a Vicious Circle. Pain in dry eye is caused by tear hyperosmolarity, loss of lubrication, inflammatory mediators and neurosensory factors, while visual symptoms arise from tear and ocular surface irregularity. Increased friction targets damage to the lids and ocular surface, resulting in characteristic punctate epithelial keratitis, superior limbic keratoconjunctivitis, filamentary keratitis, lid parallel conjunctival folds, and lid wiper epitheliopathy. Hybrid dry eye disease, with features of both aqueous deficiency and increased evaporation, is common and efforts should be made to determine the relative contribution of each form to the total picture. To this end, practical methods are needed to measure tear evaporation in the clinic, and similarly, methods are needed to measure osmolarity at the tissue level across the ocular surface, to better determine the severity of dry eye. Areas for future research include the role of genetic mechanisms in non-Sjögren syndrome dry eye, the targeting of the terminal duct in meibomian gland disease and the influence of gaze dynamics and the closed eye state on tear stability and ocular surface inflammation.
Collapse
Affiliation(s)
- Anthony J Bron
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK; Vision and Eye Research Unit, Anglia Ruskin University, Cambridge, UK.
| | - Cintia S de Paiva
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Sunil K Chauhan
- Schepens Eye Research Institute & Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Stefano Bonini
- Department of Ophthalmology, University Campus Biomedico, Rome, Italy
| | - Eric E Gabison
- Department of Ophthalmology, Fondation Ophtalmologique Rothschild & Hôpital Bichat Claude Bernard, Paris, France
| | - Sandeep Jain
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Erich Knop
- Departments of Cell and Neurobiology and Ocular Surface Center Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Maria Markoulli
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
| | - Yoko Ogawa
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Victor Perez
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA
| | - Yuichi Uchino
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Norihiko Yokoi
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Driss Zoukhri
- Tufts University School of Dental Medicine, Boston, MA, USA
| | - David A Sullivan
- Schepens Eye Research Institute & Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| |
Collapse
|
23
|
Meibomian glands, meibum, and meibogenesis. Exp Eye Res 2017; 163:2-16. [PMID: 28669846 DOI: 10.1016/j.exer.2017.06.020] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/14/2017] [Accepted: 06/28/2017] [Indexed: 12/28/2022]
Abstract
Meibum is a lipid-rich secretion that is produced by fully differentiated meibocytes in the holocrine Meibomian glands (MG) of humans and most mammals. The secretion is a part of a defense mechanism that protects the ocular surface from hazardous environmental factors, and from desiccation. Meibomian lipids that have been identified in meibum are very diverse and unique in nature. The lipid composition of meibum is different from virtually any other lipid pool found in the human body. In fact, meibum is quite different from sebum, which is the closest secretion that is produced by anatomically, physiologically, and biochemically related sebaceous glands. However, meibum of mice have been shown to closely resemble that of humans, implying similar biosynthetic mechanisms in MG of both species. By analyzing available genomic, immunohistochemical, and lipidomic data, we have envisioned a unifying network of enzymatic reactions that are responsible for biosynthesis of meibum, which we call meibogenesis. Our current theory is based on an assumption that most of the biosynthetic reactions of meibogenesis are catalyzed by known enzymes. However, the main features that make meibum unique - the ratio of identified classes of lipids, the extreme length of its components, extensive ω-hydroxylation of fatty acids and alcohols, iso- and anteiso-branching of meibomian lipids (e.g. waxes), and the presence of rather unique complex lipids with several ester bonds - make it possible that either the activity of known enzymes is altered in MG, or some unknown enzymes contribute to the processes of meibogenesis, or both. Studies are in progress to elucidate meibogenesis on molecular level.
Collapse
|