Nano-composite system of traditional Chinese medicine for ocular applications: molecular docking and three-dimensional modeling insight for intelligent drug evaluation.

The absorption of drugs was impeded in the posterior part of the eye due to the special structure. In addition, it was crucial to comprehend transport laws of molecules in ocular drug delivery for designing effective strategies. However, the current quality evaluation methods of the eye were backward and lack of dynamic monitoring of drug processes in vivo. Herein, nano-drug delivery system and three-dimensional (3D) model were combined to overcome the problems of low bioavailability and diffusion law. The model drugs were screened by molecular docking. The flexible nano-liposome (FNL) and temperature-sensitive gel (TSG) composite formulation was characterized through comprehensive evaluation. COMSOL software was utilized to build 3D eyeball to predict the bioavailability of drugs. The size of the preparation was about 98.34 nm which is relatively optimal for the enhanced permeability of the eyes. The formulation showed a stronger safety and non-irritant. The pharmacokinetics results of aqueous humor showed that the AUC of two drugs in this system increased by 3.79 and 3.94 times, respectively. The results of 3D calculation model proved that the concentrations of drugs reaching the retina were 1.90×10-5 mol/m3 and 6.37×10-6 mol/m3. In conclusion, the FNL-TSG markedly improved the bioavailability of multiple components in the eye. More importantly, a simplified 3D model was developed to preliminarily forecast the bioavailability of the retina after drug infusion, providing technical support for the accurate evaluation of ocular drug delivery. It provided new pattern for the development of intelligent versatile ophthalmic preparations.

Topical retinoic acid induces corneal strengthening by upregulating transglutaminase 2 in murine cornea.

Transglutaminase 2 (TG2) is the most abundant crosslinking enzyme in murine and human cornea, while retinoids are well-known inducers of TG2 expression. This study aims to determine if the retinoic acid supplementation can increase corneal stiffness by crosslinking through upregulating the corneal TG2 expression. The right eyes of C57BL/6 mice were treated with 2 × 10-2M retinol palmitate (VApal) eyedrops or control eyedrops and hold for 30 min, once a day for 28 consecutive days. The WB and qPCR results showed increased expression of TG2 in murine cornea with the prolongation of VApal eyedrop application. After 28 days of VApal eyedrop treatment, the increased TG2 were found catalytically active and distributed in corneal epithelium and stroma as detected by 5-(biotinamido) pentylamine (5-BP) incorporation method and immunofluorescence staining. The transmission electron microscope image revealed that VApal treated cornea manifested with increased collagen density in anterior and middle layer of stroma. The higher elastic module was found among VApal treated cornea by nano-indentation test. In cultured corneal epithelial cells and keratocytes, all-trans retinoid acid (ATRA) treatment increased the content of TG2 in cell lysis and in culture medium. These results indicate that retinoic acid induce the reinforcement of the cornea by TG2 mediated crosslinking via increasing the TG2 expression in corneal epithelium and keratocyte. As TG2 was found to be less in the cornea of keratoconus patients in several RNA-sequencing studies, retinoic acid could serve as a non-invasive prevention method for keratoconus progression.

Stable Atropine Loaded Film As a Potential Ocular Delivery System For Treatment Of Myopia.

PURPOSE: The objective of the present study was to prepare stable and high bioavailability ocular atropine loaded films (ATR-films) as potential ocular drug delivery systems for the treatment of myopia. METHODS: ATR-films were prepared by the solvent casting method and the physical properties of films were evaluated including thickness, water content, light transparency, disintegration time, and mechanical properties. FT-IR, DSC, XRD, TGA, AFM, and Raman spectroscopy were performed to characterize the film. The stability test was conducted under different conditions, such as high humidity, high temperature, and strong light. The pharmacokinetic study and irritation assessment were conducted in rabbits. The efficacy of ATR-films was evaluated by refraction and ocular biometry in myopia guinea pigs. RESULT: After optimizing the formulation, the resulting ATR-film was flexible and transparent with lower water content (8.43% ± 1.25). As expected, the ATR-film was stable and hydrolysate was not detected, while the content of hydrolysate in ATR eye drops can reach up to 8.1867% (limit: < 0.2%) in the stability study. The safety assessment both in vitro and in vivo confirmed that the ATR-film was biocompatible. Moreover, the bioavailability (conjunctiva 3.21-fold, cornea 2.87-fold, retina 1.35-fold, sclera 2.05-fold) was greatly improved compared with the ATR eye drops in vivo pharmacokinetic study. The pharmacodynamic study results showed that the ATR-film can slow the progress of form-deprivation myopia (~ 100 ± 0.81D), indicating that it has a certain therapeutic effect on form-deprivation myopia. CONCLUSION: The ATR-film with good stability and high bioavailability will have great potential for the treatment of myopia.

Combined Phialemonium curvatum and Acanthamoeba Keratitis: The Importance of Early Diagnosis and Specific Therapy.

PURPOSE: To report the clinical and confocal findings of a unique case of combined Phialemonium curvatum and Acanthamoeba keratitis and to highlight the role of the prompt diagnosis and specific medical treatment in preserving visual function. METHODS: A case report and literature review. RESULTS: A 54-year-old woman presented with a 3-day history of visual impairment, photophobia, and ocular pain in her right eye. Her best corrected visual acuity was 0.4 Logarithm of the Minimum Angle of Resolution scale, and the slit-lamp examination showed whitish corneal stromal infiltrate with satellite lesions. In vivo confocal microscopy evidenced Acanthamoeba cysts and fungal hyphae that resulted P. curvatum in the culture examination. The intensive medical treatment was started with topical 0.02% polyhexamethylene biguanide, voriconazole 1%, and moxifloxacin hydrochloride 0.5%. Progressive improvement of clinical and confocal pictures was registered with a complete recovery of visual function after 1 month. CONCLUSIONS: This is the first case report of combined P. curvatum and Acanthamoeba keratitis. The fast diagnosis with in vivo confocal microscopy allowed early and intensive specific treatment with recovery of corneal infection.

Simplified, Readily Available Method for the Treatment of Band Keratopathy With Ethylenediaminetetraacetic Acid.

PURPOSE: To compare 3 methods for creating ethylenediaminetetraacetic acid (EDTA) solution using readily available Vacutainer tubes for the treatment of band keratopathy. METHODS: All 3 protocols used commercially available Vacutainer blood collection tubes coated with K2EDTA. An osmometer was used to measure and compare the concentration of EDTA created using 3 different protocols. The time required for preparation of the solution was measured and compared to evaluate its efficiency for everyday clinical use. In addition, volume of EDTA solution obtained was measured for method 1. The most promising protocol for clinical use was then used for treatment of a series of patients. RESULTS: Average osmolarity was 532, 285, and 422 for methods 1, 2, and 3, respectively (ANOVA P < 0.01, all Tukey honestly significant difference P < 0.01). For the respective mixtures, average concentration was 65, 35, and 52 mg/mL, and average time to create solution was 189, 38, and 83 seconds (ANOVA P < 0.01, all Tukey honestly significant difference P < 0.01). The most promising, method 3, was found to be safe and effective in removing calcium from the corneal stroma in a series of 5 patients with 6 eyes treated. It also yielded 25% more solution for clinical use than method 1. CONCLUSIONS: Method 3 using a single 10-mL Vacutainer tube with 18 mg of K2-EDTA had the best balance of effective concentration of EDTA, time to preparation, and simplicity of methodology, when compared with previously published methods 1 and 2. It also yielded a greater final volume of solution.

The anti-scarring role of Lycium barbarum polysaccharide on cornea epithelial-stromal injury.

PURPOSE: Cornea epithelial-stromal scarring is related to the differentiation of fibroblasts into opaque myofibroblasts. Our study aims to assess the effectiveness of Lycium barbarum polysaccharide (LBP) solution as a pre-treatment in minimizing corneal scarring. METHODS: Human corneal fibroblasts were cultured in a three-dimensional collagen type I-based hydrogel in an eye-on-a-chip model. Fibroblasts were pre-treated with 2 mg/mL LBP for 24 h, followed by another 24-h incubation with 10 ng/mL transforming growth factor-beta 1 (TGF-ß1) to induce relevant physiological events after stromal injury. Intracellular pro-fibrotic proteins, extracellular matrix proteins, and pro-inflammatory cytokines that involved in fibrosis, were assessed using immunocytochemistry and enzyme-linked immunosorbent assays. RESULTS: Compared to the positive control TGF-ß1 group, LBP pre-treated cells had a significantly lower expression of alpha-smooth muscle actin, marker of myofibroblasts, vimentin (p < 0.05), and also extracellular matrix proteins both collagen type II and type III (p < 0.05) that can be found in scar tissues. Moreover, LBP pre-treated cells had a significantly lower secretion of pro-inflammatory cytokines interleukin-6 and interleukin-8 (p < 0.05). The cell-laden hydrogel contraction and stiffness showed no significant difference between LBP pre-treatment and control groups. Fibroblasts pretreated with LBP as well had reduced angiogenic factors expression and suppression of undesired proliferation (p < 0.05). CONCLUSION: Our results showed that LBP reduced both pro-fibrotic proteins and pro-inflammatory cytokines on corneal injury in vitro. We suggest that LBP, as a natural Traditional Chinese Medicine, may potentially be a novel topical pre-treatment option prior to corneal refractive surgeries with an improved prognosis.

Repurposing of nifedipine loaded in situ ophthalmic gel as a novel approach for glaucoma treatment.

Glaucoma is a chronic eye disease characterized by elevated intraocular pressure (IOP) which causes severe complications to the eyes and may lead to vision loss. The effective treatment of such diseases motivated the search for novel and unique drugs and delivery systems. It has been reported that, nifedipine (NF) is effective in reducing the elevated IOP due to vasodilatation of eye vascular smooth muscles. NF loaded thermo-sensitive in situ gels were prepared by the cold method using poloxamer 407 (P407) and hydroxypropyl methyl cellulose (HPMC) polymers adopting Box-Behnken experimental design. All the prepared formulae were tested for homogeneity, clarity, pH, isotonicity, gelling capacity, rheological behavior, in vitro drug release and were tested in vivo on rabbits. The prepared in situ gels were homogenous, transparent, having a pH ranged from 5 to 5.5 and undergo sol-gel transition within few seconds physiological temperature. The in situ gels showed sustained in vitro release of NF where about 76% of the loaded drug was released over 12 h. NF loaded in situ gels showed a 45.83 ± 2.91% reduction in the IOP, with no sign of toxicity or irritation to the eye in rabbits. The current investigations clarified the efficiency of this novel and unique NF loaded in situ gel for the control of the IOP compared to the conventional ophthalmic dosage forms.

Polyvinyl Alcohol/Chitosan Single-Layered and Polyvinyl Alcohol/Chitosan/Eudragit RL100 Multi-layered Electrospun Nanofibers as an Ocular Matrix for the Controlled Release of Ofloxacin: an In Vitro and In Vivo Evaluation.

A novel nanofiber insert was prepared with a modified electrospinning method to enhance the ocular residence time of ofloxacin (OFX) and to provide a sustained release pattern by covering hydrophilic polymers, chitosan/polyvinyl alcohol (CS/PVA) nanofibers, with a hydrophobic polymer, Eudragit RL100 in layers, and by glutaraldehyde (GA) cross-linking of CS-PVA nanofibers for the treatment of infectious conjunctivitis. The morphology of the prepared nanofibers was studied using scanning electron microscopy (SEM). The average fiber diameter was found to be 123 ± 23 nm for the single electrospun nanofiber with no cross-linking (OFX-O). The single nanofibers, cross-linked for 10 h with GA (OFX-OG), had an average fiber diameter of 159 ± 30 nm. The amount of OFX released from the nanofibers was measured in vitro and in vivo using UV spectroscopy and microbial assay methods against Staphylococcus aureus, respectively. The antimicrobial efficiency of OFX formulated in cross-linked and non-cross-linked nanofibers was affirmed by observing the inhibition zones of Staphylococcus aureus and Escherichia coli. In vivo studies using the OFX nanofibrous inserts on a rabbit eye confirmed a sustained release pattern for up to 96 h. It was found that the cross-linking of the nanofibers by GA vapor could reduce the burst release of OFX from OFX-loaded CS/PVA in one layer and multi-layered nanofibers. In vivo results showed that the AUC0-96 for the nanofibers was 9-20-folds higher compared to the OFX solution. This study thus demonstrates the potential of the nanofiber technology is being utilized to sustained drug release in ocular drug delivery systems.

Comparison of therapeutic effects between topical 8-oxo-2'-deoxyguanosine and corticosteroid in ocular alkali burn model.

We compared the therapeutic effects of topical 8-oxo-2'-deoxyguanosine (8-oxo-dG) and corticosteroid in a murine ocular alkali burn model. (n = 128) The corneal alkali burn model was established by applying 0.1 N sodium hydroxide (NaOH), followed by treatment with 8-oxo-dG, 0.1% fluorometholone (FML), 1% prednisolone acetate (PDE), or phosphate-buffered saline (PBS) twice daily. One week later, the clinical and histological status of the cornea were assessed. Transcript levels of inflammatory cytokines and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase as well as the levels of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the cornea, were assayed. The 8-oxo-dG and PDE groups showed marked improvements in corneal integrity and clarity when compared with the PBS group (each p < 0.01). The numbers of cells stained for neutrophil elastase and F4/80-positive inflammatory cells were significantly decreased, with levels of interleukin(IL)-1ß, IL-6, tumor necrosis factor(TNF)-α, and total ROS/RNS amounts markedly reduced in the 8-oxo-dG, FML, and PDE groups (each p < 0.05). Levels of NADPH oxidase type 2 and 4 were substantially more repressed in the 8-oxo-dG-treated group than in the PDE-treated group (each p < 0.05). Topical 8-oxo-dG showed excellent therapeutic effects that were comparable with those treated with topical PDE in a murine ocular alkali burn model.

Experimental design, formulation and in vivo evaluation of a novel topical in situ gel system to treat ocular infections.

In situ gels have been extensively explored as ocular drug delivery system to enhance bioavailability and efficacy. The objective of present study was to design, formulate and evaluate ion-activated in situ gel to enhance the ocular penetration and therapeutic performance of moxifloxacin in ophthalmic delivery. A simplex lattice design was utilized to examine the effect of various factors on experimental outcomes of the in situ gel system. The influence of polymers (independent variables) such as gellan gum (X1), sodium alginate (X2), and HPMC (X3) on gel strength, adhesive force, viscosity and drug release after 10 h (Q10) were assessed. Selected formulation (MH7) was studied for ex vivo permeation, in vivo irritation and pharmacokinetics in rabbits. Data revealed that increase in concentration of polymers led to higher gel strength, adhesive force and viscosity, however, decreases the drug release. MH7 exhibited all physicochemical properties within acceptable limits and was stable for 6 months. Release profile of moxifloxacin from MH7 was comparable to the check point batches and followed Korsmeyer-Peppas matrix diffusion-controlled mechanism. Ocular irritation study signifies that selected formulation is safe and non-irritant for ophthalmic administration. In vivo pharmacokinetics data indicates significant improvement of moxifloxacin bioavailability (p < 0.0001) from MH7, as evidenced by higher Cmax (727 ± 56 ng/ml) and greater AUC (2881 ± 108 ng h/ml), when compared with commercial eye drops (Cmax; 503 ± 85 ng/ml and AUC; 978 ± 86 ng h/ml). In conclusion, developed in situ gel system (MH7) could offers a more effective and extended ophthalmic therapy of moxifloxacin in ocular infections when compared to conventional eye drops.

Pharmacokinetics and Pharmacology of Latanoprost 0.005% without Benzalkonium Chloride Vs Latanoprost 0.005% with Benzalkonium Chloride in New Zealand White Rabbits and Beagles.

Purpose: Many intraocular pressure (IOP)-lowering medications contain benzalkonium chloride (BAK), a preservative associated with unfavorable outcomes.A formulation of latanoprost 0.005% ophthalmic without BAK is approved by the FDA and indicated for reduction of IOP in patients with open-angle glaucoma or ocular hypertension. We present two preclinical studies of latanoprost 0.005% BAK-free vs latanoprost with BAK; one examining plasma and ocular tissue pharmacokinetics (PK) in New Zealand white rabbits, and one comparing in vivo IOP-lowering efficacy in healthy beagles.Methods: In the PK study, one drop of treatment (latanoprost BAK-free or latanoprost with BAK) was instilled into both eyes of rabbits in each treatment group (n = 18). At 0.25, 0.5, 1, 4, 6, and 24 hours postdose, three rabbits per study group underwent terminal blood and tissue collection.In the IOP study, in the first dosing period, both eyes of each beagle received either 1 drop latanoprost BAK-free or latanoprost with BAK, once daily for 10 days. After a 10-day washout period, a second 10-day dosing period was conducted and latanoprost BAK-free or latanoprost with BAK were dosed in the opposite eyes, respectively. IOP measurements were taken at 1, 6, and 12 hours postdose.Results: The maximum plasma concentration for latanoprost BAK-free and latanoprost with BAK occurred 0.25 hours after administration (174.1 vs 217.2 pg/mL, respectively). Area under the concentration time curve from zero to infinity was highest in aqueous humor for latanoprost BAK-free and latanoprost with BAK (133.1 vs 119.6 hr·ng/mL, respectively) and was not estimable in vitreous humor. In beagles, once-daily administration of latanoprost BAK-free or latanoprost with BAK led to a significant reduction in IOP vs baseline (P < .001); there was no difference between groups (P > .05).Conclusions: Latanoprost BAK-free showed comparable activity in reducing IOP, and comparable plasma and ocular PK parameters to latanoprost with BAK.

Treatment of Severe Acute Bacterial Keratitis in Rabbits Using Continuous Topical Ocular Instillation with Norvancomycin.

PURPOSE: Efficacy of norvancomycin (NVCM) through continuous topical ocular instillation drug delivery (CTOIDD) system for treating severe acute bacterial keratitis infection with Staphylococcus aureus was investigated. METHODS: Rabbits with bacterial keratitis were treated using CTOIDD with NVCM (n=13), topical NVCM eye drops (n=11), and CTOIDD with saline (n=8). Clinical signs of keratitis in all groups were assessed consecutively for a week. Bacterial quantification of excised corneas was counted on the fourth and eighth days. Histopathologic examinations were performed to assess inflammatory cell infiltration on the eighth day. RESULTS: All signs of bacterial keratitis were alleviated in CTOIDD with NVCM according to criteria, and the CTOIDD-NVCM group had significantly less inflammation than CTOIDD-saline (p<0.05), and eye drop-NVCM (p<0.05). Two eyes in the eye drop-NVCM group, four eyes in the CTOIDD-saline group had corneal perforation (CP), while none of the rabbits showed CP in the CTOIDD-NVCM group. Bacterial counts were significantly less in the CTOIDD with NVCM group in comparison to the eye drop-NVCM (p<0.05), and CTOIDD-saline (p<0.05) groups. Severe inflammation and marked inflammatory cell infiltration were found in histopathologic examinations in the CTOIDD-saline and eye drop-NVCM groups, while significantly less inflammation was documented in the CTOIDD-NVCM (p<0.05) group. CONCLUSION: CTOIDD with NVCM effectively reduced the severity and treated acute bacterial S. aureus keratitis infection in a rabbit model. The presented approach of CTOIDD with NVCM appears to be a promising therapeutic approach for severe acute bacterial keratitis.

Preparation and Evaluation of a Xanthan Gum-Containing Linezolid Ophthalmic Solution for Topical Treatment of Experimental Bacterial Keratitis.

PURPOSE: To formulate a xanthan gum-containing linezolid ophthalmic solution (LZD-XG) as a new antibiotic treatment against ocular bacterial infection. METHODS: LZD-XG was prepared and evaluated for its in vitro/in vivo ocular tolerance, in vitro/in vivo antibacterial activity, and in vivo ocular penetration. RESULTS: The optimized LZD-XG exhibited good in vitro/in vivo eye tolerance. A prolonged ocular surface residence time of LZD-XG was observed after topical instillation, and the ocular permeation was significantly better for LZD-XG than fora linezolid (LZD) ophthalmic solution. The in vitro antimicrobial activity was significantly better with LZD-XG than with LZD. In vivo evaluation also confirmed a strong therapeutic treatment effect of LZD-XG, as it significantly improved the clinical symptoms, ameliorated the damage of Staphylococcus aureus to ocular tissues, lowered the colony forming unit counts in the cornea, and decreased the myeloperoxidase activity in the cornea. CONCLUSION: LZD-XG was deemed a viable ophthalmic solution against ocular bacterial infection due to its excellent in vitro and in vivo characterizations.

Efficacy of Topical Ivermectin for the Treatment of Cutaneous and Ocular Rosacea.

Purpose: To investigate the efficacy of once-daily topical treatment of ocular and cutaneous rosacea with ivermectin 1% cream (Soolantra®, Galderma).Methods: Ten patients with rosacea were evaluated in a retrospective monocentric pilot study. Subjective symptoms (measured with the Ocular Surface Disease Index), skin findings, and ocular changes (blepharitis with telangiectasia and meibomian gland dysfunction, conjunctival redness, tear breakup time (TBUT), and fluorescein staining of the cornea) were evaluated. The follow-up was 8 months (range: 5-12 months).Results: The OSDI score decreased in the 8th week of treatment (38.5 ± 21.7, P = .004). After 16 weeks, blepharitis (P = .004), and conjunctival redness (P = .008) had strongly improved, and grade 1 was seen in all patients until the end of follow-up. Fluorescein staining of the cornea (P = .001) and TBUT (P = .016) showed significant improvement until the last follow-up visit. No side effects were observed. Conclusion: Topical ivermectin cream 1% given daily is an effective and safe therapy against rosacea.

Efficacy of Alcaftadine 0.25% (AGN-229666) for Once-daily Prevention of Cedar-Pollen Allergic Conjunctivitis: A Phase 3 Randomized Study.

Purpose: This study evaluated the efficacy and safety of once-daily Alcaftadine 0.25% (AGN-229666) for prevention of signs and symptoms of Japanese cedar-pollen allergic conjunctivitis.Methods: This was a single-center, placebo-, and comparator-controlled study using the Ora-CAC® model of allergic conjunctivitis. The primary endpoint was ocular itching 16 hours after Alcaftadine 0.25% instillation; efficacy at 16 hours was compared with 0.1% Olopatadine, 4 hours after instillation. Secondary endpoints included conjunctival hyperemia.Results: 263 Japanese subjects were enrolled; 224 completed the trial. Alcaftadine 0.25% was statistically superior to vehicle for relief of ocular itching at 16 hours (p < .0001). Alcaftadine 0.25% at 16 hours was non-inferior to Olopatadine at 4 hours. Alcaftadine 0.25% was significantly better than vehicle for relief of conjunctival hyperemia. All treatments showed a low frequency of ocular adverse events.Conclusion: Once-daily Alcaftadine 0.25% is safe and effective in preventing signs and symptoms of Japanese cedar-pollen allergic conjunctivitis.

Anterior Segment Surgeries Under Topical Fresh Frozen Plasma Treatment in Ligneous Conjunctivitis.

PURPOSE: To evaluate the efficacy of topical fresh frozen plasma (FFP) therapy on clinical symptoms, findings, and prognosis after anterior segment surgeries in patients with ligneous conjunctivitis (LC). METHODS: Retrospective case note review. RESULTS: Eleven eyes of 7 cases whose remission was not achieved after medical treatment such as topical corticosteroids, cyclosporine A, and heparin were included in the study. The median age of admission was 19 (1-49) years, median duration of FFP treatment was 48 (15-79) months, median follow-up period was 62 (16-114) months, and median age at symptom onset was 12 (4-252) months. Diagnosis was made according to clinical presentations, plasminogen activities, and response to treatment. Topical FFP that was prepared in our clinic was used in all cases. Surgeries (membrane excision, eyelid surgery, deep anterior lamellar keratoplasty, and cataract surgery) were performed after at least 1 month of FFP treatment. Prosthetic contact lens was applied to one eye. During the follow-up period, recurrences requiring membrane excision and side effects from topical FFP were not observed. CONCLUSIONS: LC is a rare membranous conjunctivitis that proceeds with remissions and recurrences. When it was shown that the etiology of LC is plasminogen deficiency, FFP became the only treatment option targeting the etiology. In this study, we observed that the topical FFP is an effective treatment method that prevents recurrence and ensures regression of membranes and safer anterior segment surgeries in LC.

Topical cell-free conditioned media harvested from adipose tissue-derived stem cells promote recovery from corneal epithelial defects caused by chemical burns.

Corneal chemical burns can lead to blindness following serious complications. As most of these complications are caused by failure of reepithelization during the acute phase, treatment at this stage is critical. Although there have been some studies on corneal injury recovery using adipose tissue-derived stem cells (ADSCs), none has reported the effect of topical cell-free conditioned culture media (CM) derived from ADSCs on corneal epithelial regeneration. Here, the best conditions for CM were selected and used for in vitro and in vivo experiments. Corneal burn in rats was induced using 100% alcohol. The chosen CM was administered to corneal burn rats (CM-treated [CT] group) four times a day for three days and this group was compared with the normal control and corneal burn (CB) groups. Biomicroscopic fluorescence images and the actual physical corneas were taken over time and used for analysis. mRNA levels of hepatocyte growth factor and epidermal growth factor (EGF) were significantly increased, whereas those of vascular endothelial growth factor, interleukin (IL)-1ß, IL-6, IL-10, and matrix metalloproteinase-9 were significantly decreased in the CT group compared with those in the CB group. The numbers of proliferating cell nuclear antigen- and zonular occludens-1-positive cells in the CT group were significantly higher than those in the CB group. The macrophage-infiltrating corneas in the CT group expressed significantly more of the M2 marker arginase than corneas in the CB group. Optimal CM (× 0.5 concentration) treatment significantly accelerated the migration of corneal epithelial cells and induced upregulation of the expression of IL-6, EGF, and C-X-C chemokine receptor type 4 mRNAs. Overall, in this study, topical administration of cell-free CM promoted regeneration of the corneal epithelium after induction of chemical burns.

Efficacy of a Novel Ophthalmic Antimicrobial Drug Combination Toward a Large Panel of Staphylococcus aureus Clinical Ocular Isolates From Around the World.

PURPOSE: Staphylococcus aureus is a leading cause of keratitis requiring urgent antimicrobial treatment. However, rising antibiotic resistance has rendered current ophthalmic antibiotics increasingly ineffective. First, a diverse, ocular S. aureus strain set was evaluated for resistance to 6 commonly used ophthalmic antibiotics. Next, a recently discovered antimicrobial drug combination containing polymyxin B/trimethoprim (PT) + rifampin that displayed impressive efficacy toward S. aureus in both in vitro and in vivo studies was evaluated as a potential novel keratitis therapeutic through testing this combination's efficacy against the clinical strain set. METHODS: A total of 163 S. aureus isolates were collected either commercially or from the Flaum Eye Institute, University of Rochester. The minimum inhibitory concentrations of moxifloxacin, levofloxacin, vancomycin, erythromycin, tobramycin, rifampin, and PT were determined for the entire strain set to establish the incidence of resistance to current treatment options among a contemporary clinical isolate set and compared with the performance of PT + rifampin. RESULTS: Among all 163 isolates tested, high rates of antibiotic resistance were found toward erythromycin (69% resistance), moxifloxacin (33%), levofloxacin (40%), and tobramycin (17%). Conversely, the entire strain set, including multidrug resistant isolates, was sensitive to PT + rifampin, demonstrating the potency of this combination. CONCLUSIONS: We established that antibiotic resistance is pervasive among clinical S. aureus isolates, underscoring the concern for the effectiveness of current ophthalmic antibiotics. The drug combination of PT + rifampin, however, eradicated 100% of isolates tested, demonstrating the ability to overcome existing circulating resistance factors, and as such, might represent a promising therapeutic for S. aureus keratitis.

The allergic eye: recommendations about pharmacotherapy and recent therapeutic agents.

PURPOSE OF REVIEW: Ocular allergies affect an estimated 40% of the population, 98% of which are because of allergic conjunctivitis. With the current advent of both repurposed drugs for ocular allergies, as well as novel drugs and methods of administration, there is a need for an updated review of current available medications. A clear characterization of each treatment will ultimately allow treating physicians to restore patients' quality of life and decrease burden of disease. RECENT FINDINGS: Currently, there are a number of reformulated antihistamines, with cetrizine being the most recent ophthalmic solution available. Nevertheless, there is ongoing research in the field of immunotherapy, steroids, flavonoids, cannabis, and drug-delivery systems. SUMMARY: Although dual-activity agents remain the keystone for treatment, newer drugs and drug-delivery systems offer other novel directions for delivering appropriate relief with minimal adverse effects.

The Protective Effects of Acer okamotoanum and Isoquercitrin on Obesity and Amyloidosis in a Mouse Model.

Obesity increases risk of Alzheimer's Disease (AD). A high fat diet (HFD) can lead to amyloidosis and amyloid beta (Aß) accumulation, which are hallmarks of AD. In this study, protective effects of the ethyl acetate fraction of Acer okamotoanum (EAO) and isoquercitrin were evaluated on obesity and amyloidosis in the HFD- and Aß-induced mouse model. To induce obesity and AD by HFD and Aß, mice were provided with HFD for 10 weeks and were intracerebroventricularly injected with Aß25-35. For four weeks, 100 and 10 mg/kg/day of EAO and isoquercitrin, respectively, were administered orally. Administration of EAO and isoquercitrin significantly decreased body weight in HFD and Aß-injected mice. Additionally, EAO- and isoquercitrin-administered groups attenuated abnormal adipokines release via a decrease in leptin and an increase in adiponectin levels compared with the control group. Furthermore, HFD and Aß-injected mice had damaged liver tissues, but EAO- and isoquercitrin-administered groups attenuated liver damage. Moreover, administration of EAO and isoquercitrin groups down-regulated amyloidosis-related proteins in the brain such as ß-secretase, presenilin (PS)-1 and PS-2 compared with HFD and Aß-injected mice. This study indicated that EAO and isoquercitrin attenuated HFD and Aß-induced obesity and amyloidosis, suggesting that they could be effective in preventing and treating both obesity and AD.