Organisms Commons^™

Localization Of Angiotensin Converting Enzyme In Rabbit Cornea And Its Role In Controlling Corneal Angiogenesis In Vivo, Ajay Sharma, Daniel I. Bettis, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Purpose: The renin angiotensin system (RAS) has been shown to modulate vascular endothelial growth factor and angiogenesis. In this study we investigated (i) the existence of the RAS components angiotensin converting enzyme (ACE) and angiotensin II receptors (AT1 and AT2) in the rabbit cornea using in vitro and ex vivo models and (ii) the effect of enalapril, an ACE inhibitor, to inhibit angiogenesis in rabbit cornea in vivo.

Methods: New Zealand White rabbits were used. Cultured corneal fibroblasts and corneal epithelial cells were used for RNA isolation and cDNA preparation using standard molecular biology techniques. PCR was performed to …

Efficacy And Safety Of Mitomycin C As An Agent To Treat Corneal Scarring In Horses Using An In Vitro Model, Dylan G. Buss, Ajay Sharma, Elizabeth A. Giuliano, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—Mitomycin C (MMC) is used clinically to treat corneal scarring in human patients. We investigated the safety and efficacy of MMC to treat corneal scarring in horses by examining its effects at the early and late stages of disease using an in-vitro model.

Procedure—An in-vitro model of equine corneal fibroblast (ECF) developed was used. The equine corneal fibroblast or myofibroblast cultures were produced by growing primary ECF in the presence or absence of transforming growth factor beta-1 (TGFβ1) under serum-free conditions. The MMC dose for the equine cornea was defined with dose-dependent trypan blue exclusion and MTT [(3-4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays …

Isolation And Cultivation Of Equine Corneal Keratocytes, Fibroblasts And Myofibroblasts, Dylan G. Buss, Elizabeth A. Giuliano, Ajay Sharma, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Objective—To establish an in vitro model for the investigation of equine corneal wound healing. To accomplish this goal, a protocol to isolate and culture equine corneal keratocytes, fibroblasts and myofibroblasts was developed.

Animal material—Equine corneal buttons were aseptically harvested from healthy research horses undergoing humane euthanasia for reasons unrelated to this study. Slit-lamp biomicroscopy was performed prior to euthanasia by a board-certified veterinary ophthalmologist to ensure that all samples were harvested from horses free of anterior segment disease.

Procedure—Equine corneal stroma was isolated using mechanical techniques and stromal subsections were then cultured. Customized media at different culture conditions was used …

Aav Serotype Influences Gene Transfer In Corneal Stroma In Vivo, Ajay Sharma, Jonathan C. K. Tovey, Arkasubhra Ghosh, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

This study evaluated the cellular tropism and relative transduction efficiency of three AAV serotypes, AAV6, AAV8 and AAV9, for corneal gene delivery using mouse cornea in vivo and donor human cornea ex vivo. The AAV6, AAV8 and AAV9 serotypes having AAV2 plasmid encoding for alkaline phosphatase (AP) gene were generated by transfecting HEK293 cell line with pHelper, pARAP4 and pRep/Cap plasmids. Viral vectors (109 vg/μl) were topically applied onto mouse cornea in vivo and human cornea ex vivo after removing the epithelium. Human corneas were processed for transgene delivery at day 5 after viral vector application. Mouse corneas were harvested …

Trichostatin A Inhibits Corneal Haze In Vitro And In Vivo, Ajay Sharma, Maneesh M. Mehan, Sunilima Sinha, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

PURPOSE. Trichostatin A (TSA), a histone deacetylase inhibitor, has been shown to suppress TGF- –induced fibrogenesis in many nonocular tissues. The authors evaluated TSA cytotoxicity and its antifibrogenic activity on TGF- –driven fibrosis in the cornea with the use of in vitro and in vivo models.

METHODS. Human corneal fibroblasts (HSFs) were used for in vitro studies, and New Zealand White rabbits were used for in vivo studies. Haze in the rabbit cornea was produced with photorefractive keratectomy (PRK) using excimer laser. Trypan blue exclusion and MTT assays evaluated TSA cytotoxicity to the cornea. Density of haze in the rabbit …

Helical Peptides Derived From Lactoferrin Bind Hepatitis C Virus Envelope Protein E2, Reem Beleid, Donna Douglas, Norman Kneteman, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Hepatitis C virus is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma infecting more than 170 million people. Hepatitis C virus envelope 2 glycoprotein (E2) binds several cell‐surface molecules that act as receptor candidates mediating hepatitis C virus entry into hepatocytes. Peptides derived from human lactoferrin have been shown to bind hepatitis C virus‐E2 protein thereby preventing hepatitis C virus entry in cultured hepatocytes. In this study, starting from a 33‐residue human lactoferrin‐derived peptide, a number of biotin‐linked α‐peptides were synthesized and investigated for their E2 protein binding activity. E2 protein from hepatitis C virus genotype 1b …

Effect Of Prophylactic And Therapeutic Mitomycin C On Corneal Apoptosis, Cellular Proliferation, Haze, And Long-Term Keratocyte Density In Rabbits, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, Pankaj C. Gupta, Steven E. Wilson

Pharmacy Faculty Articles and Research

PURPOSE—To determine the mechanism through which topical mitomycin C prevents and treats corneal haze after photorefractive keratectomy (PRK) and to examine the effects of dosage and duration of exposure.

METHODS—In 224 New Zealand rabbits, −9.0 diopter PRK with mitomycin C or balanced salt solution was performed. Haze level was graded at the slit-lamp. Rabbits were sacrificed at 4 hours, 24 hours, 4 weeks, or 6 months after surgery and immunohistochemistry was performed with TUNEL assay, Ki67 and α-SMA.

RESULTS—TUNEL-positive apoptotic cells marginally increased in all mitomycin C groups whereas Ki67-positive mitotic cells decreased significantly following mitomycin C application. A greater …

Stromal Haze, Myofibroblasts, And Surface Irregularity After Prk, Marcelo V. Netto, Rajiv R. Mohan, Sunilima Sinha, Ajay Sharma, William Dupps, Steven E. Wilson

Pharmacy Faculty Articles and Research

The aim of this study was to investigate the relationship between the level of stromal surface irregularity after photorefractive keratectomy (PRK) and myofibroblast generation along with the development of corneal haze.

Variable levels of stromal surface irregularity were generated in rabbit corneas by positioning a fine mesh screen in the path of excimer laser during ablation for a variable percentage of the terminal pulses of the treatment for myopia that does not otherwise generate significant opacity. Ninety-six rabbits were divided into eight groups[.]

Slit lamp analysis and haze grading were performed in all groups. Rabbits were sacrificed at 4 hr …

Dextran-Methylprednisolone Succinate As A Prodrug Of Methylprednisolone: Plasma And Tissue Disposition, Xiaoping Zhang, Reza Mehvar

Pharmacy Faculty Articles and Research

Plasma and tissue disposition of a macromolecular prodrug of methylprednisolone (MP), dextran (70 kDa)–methylprednisolone succinate (DMP), was studied in rats. Single 5‐mg/kg doses of DMP or unconjugated MP were administered into the tail veins of different groups of rats (n  = 4/group/time point). Blood (cardiac puncture) and tissues (liver, spleen, kidney, heart, lung, thymus, and brain) were collected at various times after DMP (0–96 h) or MP (0–2 h) injections. Concentrations of DMP and MP in samples were analyzed by size‐exclusion chromatography (SEC) and reversed‐phase high‐performance liquid chromatography (HPLC), respectively. Conjugation of MP with 70‐kDa dextran resulted in 22‐, …

Role Of KAtp Channels In Reduced Antinociceptive Effect Of Morphine In Streptozotocin-Induced Diabetic Mice, Vivek Sood, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The nociceptive effect was measured using withdrawal latency in tail flick test in mice rendered diabetic by administering streptozotocin (200 mg/kg, i.p.). The antinociceptive effect of morphine (4 and 8 mg/kg, s.c.) and cromakalim, a KATP channel opener, (0.3, 1 and 2 micrograms, i.c.v.) was significantly reduced in diabetic mice. Moreover, co-administration of cromakalim(0.3 microgram) did not alter the reduced antinociceptive effect of morphine(4 mg/kg) in diabetic mice. Spleenectomy in diabetic mice restored the decrease in antinociceptive effect of morphine and cromakalim. Multiple dose treatment with insulin to maintain euglycaemia for 3 days in diabetic mice prevented the decrease in …

Effect Of Actinomycin D And Cycloheximide On Ischemic Preconditioning-Induced Delayed Cardioprotective Effect In Rats, Devinder Singh, Ajay Sharma, Manjeet Singh

Pharmacy Faculty Articles and Research

The present study was designed to investigate the effect of actinomycin D, a transcription inhibitor, and cycloheximide, a translation inhibitor, on the delayed cardioprotective effect of ischemic preconditioning. Left thoracotomy was performed in anaesthetized rats at 4th/5th intercostal space and polypropylene suture (5-0) was employed to occlude left common coronary artery. Ischemic preconditioning was produced by four episodes of 5 min of coronary artery occlusion followed by 5 min of reperfusion and thoracic cavity was sutured. Left thoracotomy was performed again after 24 hr of ischemic preconditioning and left coronary artery was occluded for 30 min followed by reperfusion for …