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Zhen Liang, Zhen Zhang, Jingjing Yang, Ping Lu, Tianyang Zhou, Jingguo Li, Junjie Zhang Henan Eye Hospital, Henan Provincial People’s Hospital & People’s Hospital of Zhengzhou University, Zhengzhou, People’s Republic of ChinaCorrespondence: Jingguo Li; Junjie ZhangHenan Eye Hospital, Henan Provincial People’s Hospital & People’s Hospital of Zhengzhou University, Number 7 Weiwu Road, Zhengzhou, People’s Republic of ChinaEmail lijingguo@zzu.edu.cn; zhangjunjie@zzu.edu.cnIntroduction: Fungal keratitis (FK) remains a severe sight-threatening disease, and case management is difficult due to ocular intrinsic barriers and drug shortages. Econazole (ECZ), a broad-spectrum antifungal agent, is limited in ocular applications due to the poor water solubility and strong irritant property.Methods: We successfully prepared solid-lipid nanoparticle-based ECZ eye drops (E-SLNs) by microemulsion method, and the physicochemical properties of E-SLNs were investigated. Corneal permeability, antifungal ability against Fusarium spp., irritation and bioavailability compared to ECZ Suspension (E-Susp) were evaluated in vitro and in vivo.Results: E-SLNs were a uniform and stable system which had an average particle size of 19 nm and a spherical morphology. E-SLNs also exhibited controlled release, enhanced antifungal activity without irritation. The pharmacokinetic analysis in vivo confirmed that E-SLNs showed an improved ocular bioavailability and the drug concentration in the cornea were above minimum inhibitory concentration (MIC) for 3 h after single administration.Conclusion: The E-SLNs colloid system is a promising therapeutic approach for fungal keratitis and could serve as a candidate strategy for other ocular diseases.Keywords: fungal keratitis, solid-lipid nanoparticles, econazole, topical administration, corneal penetration

Telomerase is an RNA-dependent DNA polymerase that synthesizes telomeric DNA sequences, which provide tandem GT-rich repeats (TTAGGG)n to compensate telomere shortening and play an important role in cellular aging and carcinogenesis.(1) Recent studies demonstrated that telomerase activity is absent in most normal human somatic cells but present in over 90% of tumor cells and immortalized cells. Human telomerase reverse transcriptase (hTERT) is the rate-limiting factor of telomerase activity and also ASODN (antisense oligodeoxynucleotides) targeting to hTERT gene represent a promising approach to tumor therapy. However, the use of ASODN is determined by combination of biological stability, successful uptake into the targeted cells, resistance to nucleases and so forth. To satisfy these conditions, the key is to establish proper delivery system to carry and protect ASODN. Accumulating data have revealed that polyethylenimine (PEI) with numerous positive charges is one of the most effective DNA-delivery systems in vitro and in vivo due to its polycationic property and proton sponge mechanism, however, it lacks the function of targeting to tumor cells. Recently, some studies indicated that coupling special ligand like NGR (N: asparagine, G: glycine, R: arginine) peptide targeting to tumor blood vessels with delivery system can enhance the efficacy of gene transfection. The purpose of this study was to investigate the effects of nanosize delivery system for antisense oligonucleotide for hTERT in vitro on EC9706 cells and in vivo on tumor tissue.

A nanosize delivery system (NDS) for oligonucleotides (ODNs) was established, and the effects mediated by NDS containing the antisense oligonucleotides (ASODNs) for hTERT mRNA on EC9706 cells were investigated by methyl thiazolyl tetrazolium (MTT) assay, RT-PCR, immunohistochemistry and flow cytometry. The inhibitory effects of ASODNs-NDS on EC9706 cells proliferation had a concentration-dependent and time-dependent manner. There was a significant difference in inhibitory rate between cell control group and ASODNs (I --VIII)-NDS groups (p0.05). However, no significant difference was found between cell control group and NDS group, SODN (sense oligonucleotide) group or ASODNs group (p0.05). After transfection of ASODNs-NDS for 72 h, the level of hTERT mRNA decreased observably compared with cell control group (p0.05), and cells apoptosis appeared in the ASODNs-NDS groups. The ASODNs complementary to the sites to which Sp1 and c-myc bind had stronger effects on EC9706 cell proliferation and apoptosis.