Abstract
To elucidate and to inhibit post-surgical fibrotic processes after trabeculectomy in glaucoma therapy, we measured gene expression in a fibrotic cell culture model, based on transforming growth factor TGF-β induction in primary human tenon fibroblasts (hTFs), and used Connectivity Map (CMap) data for drug repositioning. We found that specific molecular mechanisms behind fibrosis are the upregulation of actins, the downregulation of CD34, and the upregulation of inflammatory cytokines such as IL6, IL11 and BMP6. The macrolide antibiotic Josamycin (JM) reverses these molecular mechanisms according to data from the CMap, and we thus tested JM as an inhibitor of fibrosis. JM was first tested for its toxic effects on hTFs, where it showed no influence on cell viability, but inhibited hTF proliferation in a concentration-dependent manner. We then demonstrated that JM suppresses the synthesis of extracellular matrix (ECM) components. In hTFs stimulated with TGF-β1, JM specifically inhibited α-smooth muslce actin expression, suggesting that it inhibits the transformation of fibroblasts into fibrotic myofibroblasts. In addition, a decrease of components of the ECM such as fibronectin, which is involved in in vivo scarring, was observed. We conclude that JM may be a promising candidate for the treatment of fibrosis after glaucoma filtration surgery or drainage device implantation in vivo.
Highlights
Glaucoma is an optic neuropathy accompanied by typical structural and functional defects, such as optic disc damage and loss of vision
Based on our established model of fibrosis in primary human tenon fibroblasts, the in silico drug screening identified small molecules from the Connectivity Map (CMap) database that may reverse the gene expression changes caused by fibrosis
Comparing to data generated as part of the cTRAP project, we see that Pearson correlations between 0.1 and 0.2 are commonly found in analyses of CMap-related data; for example, in the cTRAP manuscript, ENCODE-based gene expression data describing a genetic perturbation were used to retrieve the same perturbation from the CMap follow-up project [24], with a Pearson correlation of 0.193 for the best match
Summary
Glaucoma is an optic neuropathy accompanied by typical structural and functional defects, such as optic disc damage and loss of vision. These features are shared by both open-angle glaucoma and angleclosure glaucoma [1]. Most glaucoma patients are first treated with anti-hypertensive eye drops [1] If this treatment is insufficient, surgical procedures are a common second-line option. To enable the drainage of aqueous humour (AH) from the anterior chamber, trabeculectomy and deep sclerectomy are performed [3]. Cyclophotocoagulation is another procedure that reduces AH production [4]. We recently investigated proteomic data of AH and found an upregulation of pro-fibrotic and inflammatory molecular mediators and of the corresponding putative mechanistic interactions among these [8]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
