Age Dordr 34 3 Cell Mol Life Sci Free Radic Biol Med J Exp Biol Methods Mol Biol Int J Sci Engin Res Prostaglandins Leukot Essent Fatty Acids J Pineal Res Cell J Biol Chem Aguirre E, Lopez-Bernardo E, Cadenas S Functional evidence for nitric oxide production by skeletal-muscle mitochondria from lipopolysaccharide-treated mice.
Mitochondrion Ahluwalia A Allometric scaling in-vitro. Sci Rep Redox Biol J Cachexia Sarcopenia Muscle PLoS Curr 5. Ainetter S Blick in die Zelle. Innovation in Tirol FEBS Lett Diabetes J Neurovirol Effects of long-chain acyl-CoA synthetase 6 knockdown in primary skeletal muscle cells metabolism. Aging Albany NY SI version. PLOS Biol 6:e Conserv Physiol 5:cox Ali SS Interrogating Egyptian mitochondria!
Oxygen-consuming and ROS-producing activities in synaptosomes. Mitochondrial function and ROS homeostasis in young mouse heart and brain: the sex factor! Early gender-related dimorphism in heart and brain mitochondria function and ROS dynamics. J Clin Endocrinol Metab Steroids Am J Hum Genet Second Extended Edition. Chem Biol Interact J Neurochem Mol Neurobiol Insect Biochem Mol Biol Free Radic Biol Med 74C Aging Cell Amo T, Brand MD Were inefficient mitochondrial haplogroups selected during migrations of modern humans?
A test using modular kinetic analysis of coupling in mitochondria from cybrid cell lines..
Biochem J PLoS One 6:e The metabolic panorama during tumor progression towards malignancy. Int J Biochem Cell Biol The energy requirement of metastatic cells. Int J Circumpolar Health Aug 5; Results: At a mean postoperative follow-up of 5. At day 60, a letter or more BCVA improvement was seen in ME relapsed in The implant was well tolerated.
There were no. At the time of intravitreal injection, 17 eyes Our results suggest that efficacy of the implant in vitrectomized eyes with uveitic ME. Before the beginning of this study, the bioavailability of different Curcumin products have been studied. Results: The treatment with Curom T M shows very good hours bioavailabilities. In the eyes of these 66 patients, we found a disappearing of one or more drusen in eyes. There was only a non-significant change of drusen size in the eyes of the 60 patients who were treated with AREDS2 supplements alone.
The anti-inflammatory agent Curcumin should be part of any treatment of nonexudative AMD. Thereby, bioavailability is of major concern.
Andreas U. Bayer , Dr. Andreas Bayer P. Patane 2. Purpose: To develop a transscleral iontophoresis applicator capable of delivering biologics to the anterior and posterior segments. Methods: The engineering designs and testing focused on optimizing conductivity, buffering capacity, product stability, and minimizing drug volume requirements. Multiple biocompatible conductive matrices were prepared and evaluated in the ocular iontophoresis applicator drug reservoir.
The devices were loaded with Cytochrome C CytC, For in vivo testing, New Zealand albino rabbits were dosed with CytC using the test devices impregnated with different biocompatible conductive matrices. Results: Following iontophoretic transport experiments in rabbits, bioanalytical results revealed that CytC was present in all ocular tissues harvested.
The levels of. CytC in conjunctiva, sclera, choroid, retina, vitreous, iris and ciliary body, and aqueous humor were quantified by triple-quad MS. The concentration of CytC in the ocular tissues increased directly with the increase in dosing solution concentration from 10 - Initial pH of dosing solution 7. Varying the current intensity 1 - 8 mA with a fixed 5 min application time enhanced the concentration of CytC in the tested ocular tissues. Likewise, increasing the iontophoretic dose at a fixed current intensity resulted in enhanced delivery of CytC to the ocular tissues.
Conclusions: The experimental results demonstrate that significant amounts of CytC can be delivered non-invasively into all rabbit ocular tissues using a novel transscleral iontophoresis ocular applicator.
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- Yue (Maria) Liu, OD, PhD - UC Berkeley School of Optometry;
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Johnson 1 , Brian D. Sippy 5 , Manju Soni 6. Results: No ocular or systemic dose limiting toxicities were identified. No retinal or choroidal vascular, inflammatory or hemorrhagic toxicities were identified. Patients reported no drug related adverse events. An interim analysis of all dose cohorts additionally showed:. Conclusions: A single injection of hI-con1, alone or in combination with anti- VEGF agents, showed no ocular or systemic safety signals.
Further studies are planned. John A. Kompella 1 A , Arun K. Upadhyay 1 B. Purpose: To develop topically applied transferrin-functionalized, biodegradable, polymeric nanoparticles to enhance and sustain diclofenac delivery for treating choroidal neovascularization. Methods: Diclofenac and Nile red loaded poly lactide-co-glycolide PLGA nanoparticles were prepared using double emulsion and solvent evaporation method. Diclofenac and Nile red were quantified using UV absorbance at nm and nm Nile red absorbance maxima in acetonitrile:water mixture , respectively.
Nanoparticles were assessed for size using Malvern nanosizer. Results: Transferrin-functionalized diclofenac PLGA nanoparticles had a mean diameter of nm and a negative zeta-potential. Drug release was sustained during the one week in vitro study. At the end of one week following single dose, diclofenac levels in rat choroid-RPE were significantly higher with functionalized PLGA nanoparticles when compared to non-functionalized nanoparticles and plain drug solution.
Conclusions: Transferrin functionalization enhances cellular delivery of nanoparticles and allows sustained and enhanced delivery of diclofenac to choroid- RPE for one week following eye drop administration. Uday B. Kompella , International Patent. Upadhyay , None. Jennifer S. Wade, Tejal A. Desai Ph. Bioengineering and Therapeutic Sciences,.
Purpose: Due to the complications associated with intravitreal injection novel drug delivery technologies are desired. These devices maximize contact surface area and provide consistent drug volume. Using the retinal epithelial cell line ARPE19, the influence of microdevice geometry and surface coating on paracellular drug delivery has been investigated. Methods: Device fabrication was achieved by a three-mask photolithography process. UV-light was used to crosslink the hydrogel in the device reservoir. Surface modification was conducted by deposition of a 1. Devices were placed in the apical chamber of an ARPE19 coated transwell insert.
Aliquots were removed from the basolateral chamber and analyzed for released drug concentration using a fluorimeter or spectrophotometer. Results: Microdevices with payloads of FD and Lucentis were succesfully fabricated. Consistent elution of FD and Lucentis from devices was achieved.
The quantity of FD transported across the ARPE19 monolayer of cells using a microdevice was greater than the amount transported using a bolus administration. The effect Chitosan coating has on the amount of drug transported is still being investigated and further optimization of the coating process will clarify if the mucoadhesive inhibits drug elution.
Conclusions: A planar microdevice capable of housing therapeutics of varying molecular weight was developed. Preliminary data suggests this device enhances. Purpose: The new studies from The Fenofibrate Intervention and Event Lowering in Diabetes FIELD reported that oral administration of fenofibrate, a relativlye safe and low cost lipid-lowering drug, prevented the progression of diabetic retinopathy DR in type 2 diabetic patients.
The purpose of this study is to evaluate if fenofibrate has therapeutic effects on DR in type 1 diabetes and if topical administration of fenofibrate is able to prevent DR in type 1 diabetes. Methods: Human retinal endothelial cells HRECs were cultured on Matrigel or Transwell inserts in the presence or absence of various concentrations of fenofibrate, the effects of fenofibrate on tube formation and cell migration were evaluated. Diabetes was induced in adult rats by injection of streptozotocin STZ. Retinal vascular leakage was evaluated by retinal vascular permeability assay, and retinal neovascularization NV was evaluated by fluorescein angiography.
Conclusions: Fenofibrate attenuates retinal angiogenesis and inflammation, and topical administration of fenofibrate has therapeutic effects on DR in type 1 diabetes. Alline M. Weng Tao 1. Purpose: Encapsulated Cell Technology ECT is designed to deliver therapeutic factors directly to the retina through a semi-permeable, hollow fiber membrane implant that encapsulates genetically modified cells. The goal of this study was to optimize ECT pre-implant culture conditions to maximize and stabilize secretion of a VEGF-antagonist targeting microgram per day daily production levels and to remove all animal and human components from the culture media.
Effects of culture media and additional supplementation on encapsulated cell protein secretion levels and encapsulated cell health were evaluated. Media supplements, including lipids, vitamins, amino acids and growth factors were added to the platform culture media in an effort to increase protein expression and optimize encapsulated cell line performance. Multiple commercial media designed for enhanced recombinant protein expression, differentiation, and viability were compared to the current platform media.
Device health and cell viability was analyzed qualitatively by the preparation of histology slides. Media analyte and metabolite concentration were evaluated using a chemistry analyzer. Results: The addition of GlutaMAX T M and removal of L-glutamine from all media led to decreased ammonia accumulation and improved encapsulated cell stability.
One animal and human component free media formulation increased protein production of the encapsulated cell line three to four fold, maintaining steady-state expression levels in micrograms per day. Most media supplements evaluated did not improve protein expression, with the exception of cholesterol. However, long- term exposure to high concentrations of cholesterol was detrimental to cell health. While select stem cell factors improved protein production, changes to cell morphology and growth rate occurred as well.
Conclusions: Optimization of media used to support ECT function resulted in identification of an improved formulation capable of achieving sustained ECT production of a VEGF antagonist at a rate of micrograms daily secretion. In addition, the absence of animal and human components enables this media to be used for clinical development and commercialization. Long-term delivery of a VEGF antagonist will potentially improve the standard-of-care treatment modality of monthly injections by providing a consistent dose, eliminating patient compliance issues and minimizing safety concerns associated with repeated injections in the eye.
Methods: A human derived cell line with a clinically tested history of safety and long-term implant viability was genetically engineered to produce a VEGF- antagonist in doses ranging from nanogram to microgram daily sustained delivery by ECT intraocular implants. Studies were conducted to determine the steady state concentrations of VEGF- antagonist in the rabbit eye over a one year period. Maximum vitreous concentrations from several encapsulated cell lines producing escalating doses of VEGF-antagonist were quantified. Controlled delivery by ECT ranged from nanogram per day to greater than 5 microgram per day sustained delivery in the.
While improvements to the production rate of the ECT implant continue, the current steady state concentration of VEGF antagonist exceeds 25 micrograms in the rabbit eye. Potential levels of VEGF-antagonist in the human eye, adjusted for the half-life of the ECT produced protein, conservatively extrapolate to concentrations greater than 50 ug, exceed the modeled levels for steady-state, standard-of-care treatments by monthly injections. Conclusions: ECT intraocular implant is capable of sustained delivery of a VEGF antagonist for periods greater than one year in the rabbit.
The ability of ECT implant to deliver an efficacious dose over sustained periods, suggest that the ECT implant would have unique advantages compared to traditional standard-of-care treatment for choroidal neovascular diseases, including improved patient compliance and safety. Most studies suggest that injections of Avastin bevacizumab every 4 weeks may be the optimal treatment although some interruption in therapy may be possible. The goal of our study was to develop a long-acting intravitreally injectable form of Avastin bound in a nanostructured porous silicon dioxide microparticles and to show the ability of these Avastin-loaded microparticles to release drug over many months.
Methods: Porous silicon dioxide was prepared by electrochemical etch of a single crystal silicon wafer in hydrofluoric acid and then oxidized. Microparticles were prepared by ultrasonic fracture. The porous silicon dioxide carrier prepared in this fashion had previosuly been shown to be non-toxic after intravitreal injection. Elution of drug into phosphate buffered saline PBS solution at pH 7.
Elution experiments were initially performed with a drug load of ug. Conclusions: Commercial Avastin can be loaded into nanoporous silicon dioxide. We loaded a total of 1 mg of Avastin into a 0. Drug releases in a linear manner maintaining a therapeutic concentration for 5. Optimized Avastin loading can increase the load to 4. A clinical trial with an Avastin-loaded porous silicon dioxide formulation is anticipated with in the next 12 months.
William R. Freeman , Spinnaker Biosciences F, I,. Taraporewala 1 , Michael J. Elman 2 , Shalom Z. Hirschman 1 , Samuel I. Backenroth 1. Purpose: To evaluate the ocular safety and ocular tissue distribution of a novel eye drop formulation of Squalamine, a potent antiangiogenic small molecule inhibitor of multiple growth factors VEGF, PDGF, bFGF with previously demonstrated systemic activity in vivo in ocular pathologies and in clinical trials for exudative macular degeneration.
Ocular toxicity and irritation were also evaluated. Conclusions: Squalamine eye drops were well tolerated, consistent with previous longer term preclinical studies in which there were no adverse clinical findings or changes in ocular histopathology. Mean posterior segment tissue concentrations of Squalamine given QD and BID exceeded the threshold at which Squalamine is known to inhibit neovascularization in a cell-based model. Squalamine has prolonged residence time and slow tissue clearance when administered QD and BID up to 14 days.
Minimal systemic uptake reduces potential systemic safety concerns. The absence of Squalamine concentrations in aqueous humor suggests a passive diffusion mechanism from anterior to posterior sclera and subsequently into the choroid. These results, consonant with previous preclinical topical data and intravenous clinical studies, warrant further clinical investigation of Squalamine eye drops to treat neovascular ophthalmic disorders.
Institute of Biomedical Engineering, wenzhou medical college, wenzhou, China. Purpose: To develop a novel injectable FK micelles and the potential application in the treatment of uveoretinitis was primarily evaluated in rat model. Briefly, 0. Finally,the product was re-suspended into 40ml water solution at 55 o C to obtain FK nanoformulation. The obtained FK nanoformulation was lyophilized and storage at 4 o C for further usage. In the rate model, rats were intravitreally injected with saline, FK, FK nanoformulation and its efficiency on the inflammation was evaluated.
Results: Due to the solubilization of MPEG-PCL co-polymer, the water solubility of FK was greatly improved,and the obtained FK nanoformulation could be freeze-dried into a power state while could re-dissolved into the water solution. As presented in Fig. Irach B. Taraporewala , Ohr Pharmaceutical I, E,. Meanwhile, the preliminary. P ; Michael J. Conclusions: In the presented paper, a novel FK micelles was developed and.
The results suggested that the application of FK nanoformulation could significantly. Giuliano Guidi, Andrea K. Weeks, Heather Sheardown. Purpose: The use of eye drops for ocular drug delivery while convenient is inefficient and poses a risk of systemic side effects. Contact lenses with a well- documented history of use in the eye represent a promising alternative vehicle. The potential of a contact lens delivery system for the prostaglandin analogue, timolol maleate was investigated and the effect of factors such as material polarity, molecular imprinting and HA were analyzed to further understand the drug- hydrogel interactions which govern the release kinetics.
The materials were prepared with and without the direct addition of 7. Molecular imprinting was accomplished and a subsequent uptake study was performed for two days using two solutions, one containing timolol in PBS at a concentration of 0. Release studies were then performed on the molecular imprinted materials using UV- spectroscopy to quantify release. Materials were also characterized by swelling and contact angles.
The effect of imprinting yields a consistent trend with both timolol and HA imprinted materials independently showing increasing release and a compounded effect when materials are imprinted with both compounds simultaneously. The increase in uptake affinity associated with timolol imprinted materials is consistent with established literature, however, the effect of HA increasing drug release is a novel result. Conclusions: It is evident the polarity of monomers, the ratio of their contribution and the nature of the therapeutic are all determining factor in uptake and release for these systems.
Hyaluronic acid imprinting appears to affect the uptake and release of therapeutics regardless of its similarity to the target compound and this. Purpose: To examine the influence of aqueous solubility on the in vivo release rate of three corticosteroids from a hydrogel punctum plug in a canine model.
The steroid in hydrogel matrix was subsequently dried and cut into punctum plugs. The plugs were inserted into the inferior canaliculus of beagles and a subset was removed each week for photographic imaging and to analyze drug content following extraction. Percent drug release was plotted over time relative to content prior to insertion. Results: As shown in Figure 1, the steroids release in vivo from the plug at a rate. Images of a steroid loaded plug demonstrating weekly drug release are seen in the bottom of Figure 1.
Conclusions: Topical corticosteroids, such as Dex, Pred and PA are used to treat inflammation in a variety of ophthalmic conditions. Many therapies require multiple daily administrations hourly for severe conditions for a prolonged period making a single dose therapy a more convenient option that may help ensure patient compliance and better provide necessary treatment.
Aside from drug potency and ocular penetration, aqueous solubility must be considered when developing an ophthalmic sustained drug delivery system, as it can greatly influence the in vivo release rate as demonstrated in the canine model. A more water soluble drug may be preferred if short term therapy is required, whereas a less soluble drug may be preferred if long term therapy is needed. Ankita Desai , Ocular Therapeutix, Inc. Michael Bassett , Ocular Therapeutix, Inc. E ; Abbe Miller ,. Ocular Thjerapeutix, Inc. E Support: None. Jacklyn H. Gilger 1. Purpose: To compare the mydriatic, mitotic, and intraocular pressure IOP effects of topical tropicamide and latanoprost when delivered as an eye drop versus delivery of the same medication via the WhisperTM device.
Methods: Six adult, female beagles were used in this study. Eyes receiving topical latanoprost via eye drops or. There were no significant. Conclusions: Drugs delivered via the WhisperTM device, an innovative approach to application of topical ocular medications, induce similar ocular effects compared to traditional eye drops when using 2 common ocular medications in the dog.
Furthermore, the latanoprost IOP data suggests that the WhisperTM device may induce a more rapid onset of effect compared to the same drug administered via an eye drop. These results strongly support the further development of this innovative device for application of topical ocular medications. Commercial Relationships: Jacklyn H. Salmon , Corinthian Ophthalmic, Inc. Gilger , Corinthian Ophthalmic, Inc. Support: None. Aba 1 , Carlos E. Lanusse 1 , Laura Moreno 1. A two-compartment model was used to simultaneously fit PRED plasma and aqueous concentration vs.
Results: The model adequately fitted the data and the estimated median interval PK parameters are shown in Table 1. A possible synergic pharmacological effect may be account for different mechanisms of action, but not for pharmacokinetic synergism and will be further studied. Commercial Relationships: Maria J. Aba , None; Carlos E. Mohannad Shawer, Martin J. Coffey, Eric Phillips. Bausch and Lomb, Rochester, NY. Purpose: To compare the vitreous buffering capacity of three species: rabbit, bovine, and porcine. This study examines the ability of the vitreous to accommodate formulations with wide ranges of pH and its effect on the local and whole vitreous pH, and clarity of the vitreous as result of such changes in its pH.
Methods: The vitreous from three species bovine, porcine, and rabbit were used for pH titration. For each measurement, a 5-mL sample of vitreous was placed in a scintillation vial and stirred. After the initial pH stabilization, the pH was recorded and aliquots of either 0. Vitreous clarity was evaluated by optical density measurements at low pH after incubation with HCl aliquots for 20 minutes. Results: Although the titration curves for the three species had some notable differences, all three species exhibited similar buffering capacity toward both acidic and basic titration.
Titration toward both acidic and basic sides over about 3 pH units showed a buffer capacity of 6. Using published information about the composition of the vitreous in various species, we can identify which vitreous components are contributing to the observed buffer capacity. The clarity of the vitreous was found to diminish at low pH. The vitreous. Conclusions: All three animal species are predicted to react similarly with regard to vitreous pH when injected with a non-neutral pH formulation.
The observed buffer capacity for the vitreous in all three species examined here is in good agreement with what would be predicted based on published information on the vitreous composition. Kevin Li 1 , 3 , William I. Higuchi 1 , 2. After 20 min of AI delivery, the rabbits were sacrificed and the eyes were enucleated. The eyes were dissected and the cornea, aqueous humor, vitreous, conjunctiva, sclera, choroid and retina analyzed for IgG content by ELISA. With regard to tissue distributions, at both current densities, most of the IgG was found in the conjunctiva and sclera at amounts roughly in proportion to their total amounts at the two current densities.
It was interesting to find that the average amounts in the deeper tissues e. Conclusions: This study might be the first to demonstrate successful noninvasive macromolecule delivery in vivo to the posterior eye tissues with the amounts of IgG delivered being of the same order of magnitude of that used in the intravitreal injection of Avastin. It was estimated that iontophoretic delivery of IgG is approximately fold superior over passive.
The volume of drug solution used as well as current density appears to be significant in AI drug delivery efficiency for both amounts. Higuchi , Aciont Inc E. Support: 1R43EY Purpose: To investigate the cell stability and in vitro performance of Encapsulated Cell Technology ECT devices using a cell line to deliver an antiangiogenic factor.
Methods: The cell line secreting the antiangiogenic factor was constructed using NTC cells. The candidate cell line was cultured for 40 passages. At predetermined passages, cells were seeded at a defined density in 24 well plates and allowed to attach. Cells were washed twice with a balanced salt solution and incubated with 1 ml of Endo-SFM for 2 hours. The pulsate was then analyzed for antiangiogenic factor release. Once cell stability had been established out to 40 passages, the cell line was encapsulated in a hollow fiber membrane.
Each device. The devices were subsequently analyzed for metabolic activity and then subjected to either total DNA or histological analysis. Unencapsulated cells and device performance were quantified by Elisa. Device metabolic activity was determined using the CCK-8 assay Dojindo. Histological examination of the devices was performed using standard hematoxylin and eosin staining techniques. Results: Cell stability: The candidate cell line released the desired factor for 40 passages which is favorable for manufacturing purposes. During this time, the cells maintained a typical and consistent morphology as well as exhibited a consistent doubling rate.
Device stability : The ECT devices released the desired factors and maintained viable cells during the evaluation period. Total DNA analysis of devices showed a consistent number of cells was maintained between 1 and 2 weeks and histological analysis of device sections showed a high density of healthy cells distributed throughout the device. Conclusions: The data suggested that the Encapsulated Cell Technology platform was able to achieve sustained delivery of antiangiogenic factors under in vitro conditions.
This technology can deliver other factors for a broad range of indications where long-term treatment is required. Luis I. Tartara, Santiago D. Palma, Daniela A. Quinteros, Marcela R. Daniel A. Allemandi, Gladys E. In vitro e In vivo performance of this formulation was assayed in rabbits. Methods: The background of the design of this formulation was the interaction between the components of the ternary complex. The biopharmaceutical performance of the formulation was evaluated by mean of In vitro corneal permeation and the In vivo effect on the intraocular pressure IOP.
This effect was sustained for four hours after instillation. In vitro corneal permeation studies demonstrated that the ACZ permeation was increased as consequence of the multicomponent complex formation. All formulations, including the commercial product, were considered practically non-irritant.
The new formulation thus obtained was to be. Commercial Relationships: Luis I. Tartara , None; Santiago D. Palma , None; Daniela A. Quinteros , None; Marcela R. Longhi , None; Daniel A. Allemandi , None; Gladys E. Gokulgandhi, Dhananjay Pal, Ashim K. Purpose: Multidrug resistance MDR proteins P-gp and MRPs mediated chemoresistance have been considered as a major cause of treatment failure in the management of retinoblastoma RB with systemic chemotherapy. Here, we have examined an interaction of fluoroquinolone moxifloxacin MFX with three anticancer drugs Topotecan, Etoposide, Vinblastine for the treatment of RB.
We hypothesized that in such interactions, MFX will not only modulate the bioavailability of anticancer agent at the ocular site such as retina due to competitive inhibition at efflux sites but it will also synergize antiproliferative activity of anticancer agent. Modulation of time dependent cell cytotoxicity and caspase-3 enzyme activity of anticancer drugs in presence of MFX was evaluated using retinoblastoma Y cells.
IC value of anticancer drugs alone and in presence of MFX was also determined. Results: Significant enhancement in caspase-3 enzyme activity of three anticancer drugs was observed in combination with MFX on Y cells. Conclusions: Strategy of utilizing efflux pump inhibitors which is yet not clinically approved for improving ocular bioavailability of anticancer agent has its own limitations in terms of little or no improvement in toxicity of chemotoxic agents. However, ocular cells have shown good tolerability against MFX, which is a clinically well accepted drug even at higher dose level.
Our results suggest that MFX may be a valuable new addition to chemotherapeutic armamentarium, concurrently improving cytotoxic activity while evading MDR mediated chemoresistance of various anticancer drugs currently used for the treatment of RB. These novel drug interactions will provide dual benefit in terms of overcoming chemoresistance and synergistic cytotoxic effect will help reducing chemotherapeutic dose which eventually reduces probability of dose-limiting toxicity.
Jonathan W. Purpose: Melphalan is an alkylating agent with effective tumoricidal properties but also severe systemic side effects. A recent clinical trial has demonstrated promising results in retinoblastoma patients when melphalan is infused selectively into the ophthalmic artery. A minority of subjects developed neutropenia, which suggests that systemic diffusion of the drug does occur. Developing a reliable systemic assay to determine plasma levels of melphalan following ophthalmic artery infusion is critical in optimizing the benefits of this treatment. Melphalan and the internal standard N-phenyldiethanolamine N-PEA were purchased from Sigma Steinhein, Germany and drug-free normal human plasma was obtained from a regional blood bank.
The extraction procedure for the concentration ranges 1 and 2 utilized uL and 50 uL plasma respectively. Blank human plasma was spiked with.
Results: Mass chromatograms for the range 1 provided eight calibration points:. A calculated ratio of the peak intensities for both melphalan and the internal standard were then used to generate a calibration curve. A calculated ratio of the peak intensities for both melphalan and the internal standard were then used to generate a second calibration curve figure 2. Ongoing aspects of the project include assay validation to demonstrate accuracy, reproducibility and stability of melphalan in human plasma.
Commercial Relationships: Jonathan W. Whitcomb 1 , Susan S. Lee 1 , Marc Horner 2 , Mohammad R.
Kazemi 3 , Michael R. Robinson 1 A , Jie Shen 1. Purpose: Ocular pharmacokinetic experiments are commonly performed in rabbits to predict the intraocular distribution of drug in humans. However, results may not translate directly to humans because of anatomical and physiological differences. Computational fluid dynamic CFD models were developed in an effort to discern the intravitreal drug distribution differences between the two species.
Methods: 3D half-globe symmetric CFD models of rabbit and human eyes were developed to simulate diffusion and convection of drug in the vitreous. The geometries were constructed using SpaceClaim Direct Modeler and anatomical dimensions were based on average values for each species. ANSYS Fluent was used to simulate the flow of vitreous humor and drug delivery from a centrally- placed bolus of fluorescent dye.
Fluorescein and fluorescein glucuronide were selected as model compounds based on available experimental data from Araie and Maurice, Results: Anatomical differences, such as a larger lens and smaller vitreous volume in the rabbit, altered the aqueous humor flow in the rabbit relative to the human.
The average drug concentration in the rabbit eye was found to be higher than the human due to the smaller vitreous volume. Conclusions: While the rabbit is an excellent animal model for studying ocular pharmacokinetics, anatomical and physiological differences should be considered when extrapolating rabbit data to human. CFD modeling can be effective to use rabbit ocular pharmacokinetic data to simulate human drug distribution.
Julie E. Whitcomb , Allergan E ; Susan S. Lee ,. Michael R. Nishizawa 1 B , Toshiaki Abe 1 A. Purpose: To evaluate the protective effects of a transscleral drug delivery device that can release geranylgeranylacetone GGA in a controlled release manner against light-induced retinal damage in rats. Methods: The device consists of a reservoir, controlled-release cover, and drug formulations, which were made of photopolymeized poly ethyleneglycol dimethacrylate that partially contains tri ethyleneglycol dimethacrylate. These parts were fabricated via a microfabrication technique that used an AutoCAD design.
High- performance liquid chromatography was used to evaluate the release amount of GGA. After the devices were placed onto the sclera of rat eyes, HSP inductions of retinal tissues were evaluated by real-time RT-PCR and western blot analyses. Flash electroretinograms were recorded 4 days after white light exposure lux for 18h. Histological examinations were perfomred to evaluate the thickness of the outer nuclear layer. Results: GGA was released with zero-ordered kinetics from the device. One or four weeks after implanation, gene and protein expression of HSP70 were upregulated in the sclera-choroid-retinal pigment epithelium fraction of the eyes treated with GGA-loaded devices compared with those treated with saline-loaded devices or non-treated rats.
Electroretinographic amplitudes of the a- and b-waves increased significantly in rats treated with GGA-loaded devices compared with saline-loaded devices. The outer nuclear layer thickness was thinned in the group treated with saline-loaded devices, but the group treated with GGA-loaded devices suppressed the photic damage. Conclusions: Transscleral GGA delivery device protected against light-induced retinal damage in rats. The device may offer a less-invasive method of drug delivery to achieve sustained release of medications for intravitreal drug delivery and the treatment of various retinal diseases.
Purpose: Corticosteroids are valuable drugs in the management of macular edema ME but therapeutic concentrations in the retina can be usually achieved only after invasive injections, making the use of topical corticosteroids not suitable for the treatment of ME. Data obtained from control eyes were considered expression of systemic absorption. Conclusions: A single topical administration of DP gel is able to deliver effective concentrations of D to the posterior segment of the eye through both systemic and topical absorption.
Mitan R. The major drawback with CDF is its low bioavailability attributable to low lipid solubility and hence poor passive transport into virus infected tissue such as retina which leads to limited therapeutic efficacy. Therefore, with a strategy to simultaneously enhancing lipid mediated and transporter targeted cellular uptake of CDF, we have evaluated novel transporter targeted lipid prodrugs of CDF for the treatment of CMV retinitis.
All synthesized prodrugs were characterized and evaluated for their physicochemical properties and cytotoxicity. To elucidate the affinity. B-CCDF 0. Conclusions: Above studies demonstrated that transporter targeted lipid prodrugs of CDF pose superior affinity for SMVT transporter and hence will have higher bioavailability into human retinal cells owing to higher expression of SMVT on the human retina.
This strategy will augment antiviral and therapeutic efficacy of CDF into retina due to synergistic effect of lipid and transporter targeting moiety. Finally, these novel prodrugs appear to be potential clinical candidates for the treatment of CMV retinitis.
Commercial Relationships: Mitan R. Anthony F. Kokx, Gary J. Purpose: The purpose of this study is to compare 3 different methods of topical anesthesia for intravitreal injections. This study will compare effectiveness of each method at achieving pre-injection anesthesia and each method's cost effectiveness. Methods: Patients already requiring an intravitreal 0. Three different methods of topical anesthesia were utilized; 3. After each injection, a pain survey point Visual Analog Scale was administered, recording pain associated with both numbing and injection. The following day, the patients used the same scale to retrospectively rate their pain from the day of the injection as well as rate their residual pain RP.
Patients had no reference to the prior survey. Results: The average number of injections prior to enrollment in the study was 4. Average post-injection IOP was 30mm Hg. Subconjunctival hemorrhage SCH was noted in 1 out of 7 patients. The average pain score for each patient all methods same day associated with the numbing method was 6.
The average pain score for each patient all methods next day associated with the numbing method was 6. The pain score in the LP group was 5. The RP was 1. There was one SCH in this group that did not have higher retrospective or residual pain scores. The pain score in the CTA group was 7. RP was 1. There were no cases of endophthalmitis. Average staffing time for each numbing protocol; LG group - Data collection will finish March Conclusions: All three anesthetic methods appear to be capable of achieving an effective level of anesthesia.
There is a range of cost and time of staffing required with each method. Commercial Relationships: Anthony F. Kokx , None; Gary J. The purpose of the current study was to investigate the pharmacokinetics PK of a VEGF antagonist delivered by an intraocular ECT implant in rabbits over a 3 months implantation period. Additionally, an arm evaluating the PK of Bevacizumab injection was included for comparison.
Methods: ECT implants were manufactured using polymer membrane encapsulated cells genetically engineered to continuously secrete a VEGF antagonist molecule, designated NT Standard-of-care injections of 1. Samples were collected at days 1, 3, 7, 14, 28, 40, 56 and 84 for both ECT implanted and injected eyes. Conclusions: Pharmacokinetics data demonstrates that ECT delivery of a VEGF antagonist can maintain microgram per eye concentrations over an extended period and the steady state level established by the ECT implant exceeds the maintenance dose established by Bevacizumab monthly intraocular injections.
Purpose: To evaluate the effects of transscleral sustained vasohibin-1 VASH delivery for rat laser-induced choroidal neovascularization CNV by a novel drug delivery device. The controlled release membrane is made of photopolymerised polyethylene glycol dimethacrylate PEGDM that contains interconnected collagen microparticle. The release was also confirmed in vivo by immunostaining 2 weeks after the device transplantation.
Fluorescein angiography and choroidal flat mounts were used to evaluate the CNV. The results of not only. Conclusions: Our device showed sustained protein release and might offer a less- invasive method than those previously reported for treatment, such as age-related macular degenelation. Biomedical, Geleen, The Netherlands. Purpose: Polyesteramides PEAs are a new family of polymeric materials. PEAs combine good mechanical, thermal and processing properties and are also biodegradable.
The purpose of the current study was to evaluate PEA-II microparticles to be used as carriers for controlled drug delivery in the eye. Methods: Microparticles MPs were prepared using an emulsion-solvent evaporation technique. Particle size and morphology of MPs were characterized by dynamic light scattering and scanning electron microscopy SEM , respectively.
In vitro tolerance studies were performed by the MTT technique in human corneal limbal epithelial cells and macrophage cells. MPs started to lose their shape after being incubated in PBS for 1 hour. DX-loaded MPs 9. Purpose: Quantification and pharmacokinetics evaluation of dexamethasone in ocular tissues after sub-tenon administration of dexamethasone-loaded PLGA microspheres in rabbits. Dexamethasone is widely used in ophthalmology to treat several ocular diseases affecting the posterior segment.
Due to short half-live of dexamethasone, repeated intraocular injections are employed in the treatment of most of these diseases. Controlled drug delivery systems, such as as microspheres MPh are being designed to avoid frequent injections. MPhs based on a biodegradable polymer PLGA have been developed to release dexamethasone in vitro for 65 days. MPhs can be periocularly administered as a conventional injection with less risk of adverse effects than intravitreal administration.
Dexamethasone concentrations in rabbit ocular tissues choroid-RPE, retina and vitreous were evaluated at different time points 1, 2, 4 and 6 weeks after injection. Samples were treated and the drug was quantified by. Results: After administration in rabbits, dexamethasone reached measurable concentrations in choroid-RPE, retina and vitreous during the six-weeks study. The tmax was observed at 2 weeks post-administration in the three tissues evaluated, with Cmax values of Calculations of area under the concentration- time curve AUC0,42d in the target tissue retina were performed as measurement of drug bioavailability, with a value of 21, Conclusions: According to the results obtained in this work, the microsphere formulation developed is suitable for sustained transscleral delivery of dexamethasone.
Periocular microspheres can be considered as a potential alternative to dexamethasone intravitreal administrations indicated for the treatment of diseases affecting the posterior segment of the eye. Knauss 2 , John. Higuchi 1 , Balbir Brar 1 , William I. Purpose: To assess the ocular tolerability of Visulex-p Vp containing dexamethasone sodium phosphate DSP following daily dosing for 7 days and weekly dosing for 12 weeks in New Zealand white rabbits.
Methods: Twenty-one months old rabbits were assigned to seven groups according to Table 1. Vp loaded with ul of the test formulation was applied to the right eye. Vp was then removed at the end of the application. The ocular examinations, with an indirect ophthalmoscope, modified McDonald-Shadduck scoring, and fluorescein staining were completed at pre-, post-, and at selected time-points post-dose.
The body weight was recorded at baseline and during the study. Results: Ocular findings are summarized in Table 1. Conjunctival injection and chemosis were observed right after dosing in all groups, with severity increasing with dosing concentrations. Resolution was observed within the days after each application. No corneal damage was seen at any of the dose groups.
No ocular findings were observed in histopathology. Knauss , Aciont. Inc F ; John W. Ciolino 1 , Cristina F. Stefanescu 2 , 3 , Katherine A. Wymbs 2 , Sarah L. Spraque 2 , Daniel R. Mascoop 2 , Shireen S. Rudina 2 , Fabiano Cade 1 , Daniel S. Kohane 3 , 2. Purpose: To report the in vivo and in vitro testing of a latanoprost-eluting contact lens designed for the treatment of glaucoma. Methods: Drug-eluting therapeutic contact lenses TCL were created by encapsulating latanoprost-Poly lactic-co-glycolic acid films in methafilcon A by ultraviolet light polymerization.
The release media was sampled and changed daily. The eyes were examined under an operating microscope and the anterior chamber AC fluid was collected during 1,. Latanoprost 0. Results: In vitro, TCLs demonstrated an initial burst and then eluted a sustained and therapeutic daily amount of latanoprost for 4 weeks. In vivo, the TCLs demonstrated no signs of toxicity. Through 14 days of continuous wear, TCLs delivered more drug to the anterior chamber each day than latanoprost drops.
Conclusions: This contact lens design can potentially be used as a treatment for glaucoma and as a platform for ocular drug delivery with widespread applications. Joseph B. Ciolino , M P ; Cristina F. Stefanescu , None; Katherine A. Wymbs , None; Sarah L. Spraque , None; Daniel R. Mascoop , None; Shireen S. Kohane , M Purpose: The objective of this study was to develop thermoresponsive and biodegradable star-branched dendritic polymers as drug carriers for drug delivery across the blood-ocular barriers.
Methods: The thermo-responsive and biodegradable star-branched dendritic polymers were synthesized using a combination of solid phase peptide synthesis, ring-opening polymerization and atom transfer radical polymerization techniques. Their thermoresponsive property was measured using both UV-vis spectroscopy to measure the transmittance and dynamic light scattering to measure the hydrodynamic size of the dendritic polymers. The permeabilities of dendritic polymers across the porcine sclera- choroid-RPE, sclera, and cornea were determined using side-by-side diffusion cells.
The DTAF-labeled nanoparticle solutions were added to the donor cell while equal volume of transport buffer was put in the receiver cell. The fluorescence intensity in the receiver cell was assayed for 4 h. Degradation studies showed that both viscosity and molecular weight decreased with time during the degradation course. MTT data indicated that the dendritic polymers were not toxic the retinal pigment epithelium RPE cells.
The ex-vivo data demonstrated that these dendritic polymers were more permeable to the porcine sclera-choroid-RPE than the control, dextran with a molecular weight of 70, Conclusions: The developed thermo-responsive and biodegradable star-branched dendritic polymers showed great potential to be used as drug carriers for deliver drug across the blood-ocular barriers.
Blessing, Peter F. Purpose: Our laboratory has reported the synthesis of multi-functional antioxidant analogs of N,N-dimethylsulfamoyl 2-pyrimidyl piperazine, which can independently chelate redox-active metals and scavenge reactive oxygen species ROS. While they readily accumulate in the lens and retina after oral administration, they fail to significantly reach the brain.
To increase the ability of these multi-functionals to cross the blood brain barrier BBB , a new series of analogs retaining the 2-aminohydroxypyrimidine ring system have been synthesized HK Here, the molecular parameters required to target these analogs to the lens, retina, or brain are defined. Methods: Molecular parameters such as log P and Clog P, that are associated with lipophilicity; dipole moment, which implies an electric moment apart from the total net charge on the molecule; kappa shape index, which is associated with steric bulk of the molecule; molar refractivity, which is related to polarizability of the molecule; and hydrophilic volume of the molecule were calculated by MOE.
The new descriptor fMF, which is associated with topology, was calculated as described in J. No significant correlations between any molecular parameter and the uptake of drugs into the neural retina were observed. Conclusions: Inverse correlations between the uptake of drugs and their molecule parameters related to steric bulk, refractivity, polarity, and hydrophilic volume, were observed in the brain versus the lens.
Although the retina is considered an extention of the brain, no correlations between the examined molecular parameters and accumulation of compound into the retina were observed. Blessing , None; Peter F. Samirkumar R. Patel 1 , Eric Powers 1 , Mark R. Prausnitz 1 , Henry F. Edelhauser 2. Purpose: Corneal infections, especially deep stromal infections, can require an aggressive therapy regimen using topically applied agents. It would be ideal to have a delivery method that can administer drug directly to the stroma to stop spread of the infection quickly without relying on patient compliance.
Here, we investigate the capability of a microneedle to infuse a fluid into the corneal stroma and study the volume that can be delivered, the pressures needed for injection and the spread of injected material. The needles were attached to tubing with an in-line pressure transducer connected to a computer for continuous pressure monitoring. The tubing was attached to a 1 mL syringe that was mounted onto a syringe pump. Images of the cornea were taken to measure the spread of the colored dye. The pressure profile during injection reached a peak within s after the injection was started and then dropped off.
The peak pressure during all injections was between psi. In these cases the pressure averaged between psi. The injected fluid spread. Large volumes, however, caused significant corneal thickening. This approach could be used to deliver drugs to the cornea for the treatment of corneal infections. Clearside Biomedical I ; Henry F. Purpose: To perform comparative analysis of pharmacokinetics of intravitreally injected bevacizumab in vitrectomized versus non-vitrectomized rabbit eyes. Methods: Among the 35 eyes of 35 rabbits included in the study, gauge pars plana vitrectomy was performed in 18 right eyes vitrectomized eyes , and the remaining 17 right eyes served as control non-vitrectomized eyes.
Both groups received 1. Bevacizumab concentrations were determined after separation of frozen vitreous and aqueous humor compartments using direct enzyme-linked immunosorbent assay. Bevacizumab concentration-time data were fit by two- compartmental analysis to determine half-life. Results: The vitreous concentration of bevacizumab in both groups showed two phases of clearance which are the fast distribution phase and the slow elimination phase.
Bevacizumab vitreous concentration in vitrectomized eye showed The calculated overall half-lives of intravitreal bevacizumab were 6. The clearance of intravitreal bevacizumab in vitrectomized eyes was accelerated only in the first phase but not in the second phase. Conclusions: The increase of intravitreal bevacizumab clearance after vitrectomy is not substantial in rabbit eyes. This experimental data suggests that the therapeutic efficacy and duration of intravitreal bevacizumab in patients who previously underwent vitrectomy may be comparable to those without vitrectomy history.
Choonara 1 A. Purpose: An autofeedback polymeric platform was used in the design of an intelligent intraocular implant - the I 3 - using stimuli-responsive polymers, producing a smart release system capable of delivering therapeutic levels of anti- inflammatory agent and antibiotic for posterior segment disorders of the eye in response to inflammation. Here the I 3 was assessed for its ability to respond to the inflammatory state created in a suitable animal model. All procedures were undertaken in accordance with ARVO. For each study, one animal in each group was euthanized at each sampling point 3, 7, 14, 21, 28 days with consequent device removal, enucleation and vitreous humor aspiration.
Device implantation in the control and experimental groups was on day 0. One animal in each group was euthanized on day 7 with device removal, enucleation and vitreous aspiration. Analysis of implant, tissue and fluid samples: Device biocompatibility and the degree of inflammation present were histologically established. The disparity in drug release behaviour in the healthy versus the inflamed rabbit eye was ascertained via analysis of vitreous samples. Results: Histological evaluation indicated that sub-Tenon device implantation did not induce a notable degree of inflammation.
There was enhanced release of both drugs in the inflamed rabbit eye even after 7 days with indomethacin levels of 0. Conclusions: The I 3 displayed exemplary inflammation-responsive behaviour following assessment in a rabbit eye model. Commercial Relationships: Lisa C. Choonara , None Support: None. Rivera, Weng Tao. Purpose: Anti-angiogenic molecules have been successfully used in the treatment of wet AMD.
The current study was carried out to explore the concept of a combination therapy - the simultaneous delivery of two biotherapeutics, each with different bioactivities, from one device. An example of a clinically relevant dual-secreting biologic device would be one that produces an anti-angiogenic VEGF antagonist and also the neuroprotective cytokine, CNTF, as dual mode therapy for Wet AMD with underlying.
VEGF antagonist expression vectors were cloned, then transfected into NTC cells followed by screening for highest productivity. The rate of. Results: Dual biologic producing clonal cell lines exhibited robust recombinant protein secretion, with levels of some cell lines approaching 15 pcd for VEGF antagonist, and 0.
Physiology Pharmacology | Angiogenesis | Clinical Medicine
Cell lines were then encapsulated, and production of recombinant proteins from individual ECT devices were detected. Berezovsky 1 , Samirkumar R. Patel 2 , Hans E. Grossniklaus 1 , Henry F. Edelhauser 1.