Minocycline and Diacetyl Minocycline Eye Drops Reduce Ocular Neovascularization in Mice

Purpose

To evaluate the efficacy of minocycline and a novel, modified minocycline analogue that lacks antimicrobial action, diacetyl minocycline (DAM), on choroidal neovascularization (CNV) in mice of both sexes.

Methods

CNV was induced via laser injury in female and male C57BL/6J mice. Minocycline, DAM, or saline was administered via topical eye drops twice a day for 2 weeks starting the day after laser injury. CNV volume was measured using immunohistochemistry labeling and confocal microscopy.

Results

Minocycline reduced lesion volume by 79% (P ≤ 0.0004) in female and male mice. DAM reduced lesion volume by 73% (P ≤ 0.001) in female and male mice. There was no significant difference in lesion volume between minocycline and DAM treatment groups or between female and male mice.

Conclusions

Both minocycline and DAM eye drops significantly reduced laser-induced CNV lesion volume in female and male mice. While oral tetracyclines have been shown to mitigate pathologic neovascularization in both preclinical studies and clinical trials, the present data are the first to suggest that tetracycline derivatives may be effective to reduce pathologic CNV when administered via topical eye drops. However, the action is unrelated to antimicrobial action. Targeted delivery of these medications via eye drops may reduce the potential for systemic side effects.

Translational Relevance

Topical administration of minocycline and/or DAM via eye drops may represent a novel therapeutic strategy for disorders involving pathologic CNV.

The preparation of lipid-based drug delivery system using melt extrusion

Melt extrusion of lipids is versatile with high applicability in the pharmaceutical industry. The formulations prepared can be easily customized depending on the requirements, and have the potential to open a window on personalized medicine.

Mouse prostate proteome changes induced by oral pentagalloylglucose treatment suggest targets for cancer chemoprevention

Recent in vitro and in vivo preclinical studies have suggested that the Oriental herbal compound penta-1, 2, 3, 4, 6-O-galloyl-beta-D-glucose (PGG) is a promising chemopreventive agent for prostate cancer. Little is known of its safety for chronic chemoprevention use and virtually nothing is known of its in vivo responsive proteins in the target organ. Here we treated male C57BL/6 mice with daily oral administration of PGG at two dosages (1 and 2 mg per mouse) from 7 to 14 weeks of age and profiled proteomic patterns in the prostate with iTRAQ labeling and 2D LC-MS/MS analyses. While neither dose affected feed intake and body weight gain, the 2 mg dose (∼80-100 mg per kg) led to a minor but statistically significant decrease of the weight of prostate and thymus. For proteomic profiling, five prostates were pooled from each group for protein extraction. Proteins were denatured, reduced, alkylated and digested to peptides. The peptides were labeled with iTRAQ reagents, mixed and subjected to 2D LC-MS/MS analyses. PGG consumption suppressed the abundance of oncoproteins (e.g., fatty acid synthase, clusterin) and up-regulated that of tumor suppressor proteins (e.g., glutathione S-transferase M), signifying changes that may contribute to prostate cancer risk reduction.