2008 Feline Health Grants
Published: March 04, 2008
Winn Feline Health Foundation

EveryCat Health Foundation
(Formerly Winn Feline Health Foundation)
www.everycat.org
2008 FELINE HEALTH GRANT AWARDS
10 projects funded for a total of $135,860

The Winn Feline Foundation receives proposals from veterinary researchers around the world who are interested in improving feline health. Out of 36 proposals for 2008, our team of outstanding veterinary consultants helped the Foundation select the best projects for funding. We look forward to seeing the results of these projects and being able to share them with the veterinary community as well as cat owners and pedigreed cat breeders.

BREED-FUNDED PROJECTS

#08-015: Molecular evaluation of the feline myosin binding protein C gene in Siberian cats with familial hypertrophic cardiomyopathy
Kathryn M. Meurs, DVM, PhD, DACVIM; Washington State University; $12,988

Feline hypertrophic cardiomyopathy (HCM) is the most common cause of heart disease in the adult cat. Affected cats are at risk of sudden cardiac death, congestive heart failure, or development of an arterial thrombus. Increasingly, feline HCM is noted to be familial, with examples reported in the Maine Coon, Ragdoll, British Shorthair, Sphynx, and Siberian breeds, among others. The investigator has demonstrated that HCM is associated with two distinct mutations in the myosin binding protein C gene in the Maine Coon and Ragdoll cat. The Siberian cat also develops a familial form of HCM. Given the importance of the myosin binding protein C gene in Ragdolls and Maine Coon cats with HCM, it is hypothesized that a mutation in this gene, perhaps in a different region, is associated with the disease in the Siberian cat. The objective of this study is to identify a causative mutation by the evaluation of the coding sequence of the myosin binding protein C gene in Siberian cats.

[This project is approved with funding from the Ricky Fund and pending funding from Siberian cat breeders.]

#08-014: Molecular evaluation of the feline alpha tropomyosin gene in Norwegian Forest, Sphynx, Siberian, Ragdoll and Maine Coon cats with familial hypertrophic cardiomyopathy
Kathryn M. Meurs, DVM, PhD, DACVIM; Washington State University; $14,242

Feline hypertrophic cardiomyopathy (HCM) is the most common cause of heart disease in the adult cat. HCM is familial in the Maine Coon (MC), Ragdoll, Sphynx, Norwegian Forest (NWF), and Siberian cats. In human beings, the disease is most commonly associated with a mutation in one of eight sarcomeric genes. The investigator has previously demonstrated that feline HCM is associated with separate mutations in the myosin binding protein C gene (MYBPC), the second most common gene to cause the human disease, in the MC and Ragdoll. However, a small number of affected Ragdoll and Maine Coon cats do not have their known breed mutations. Evaluation of four sarcomeric genes (MYBPC, myosin heavy chain gene, troponin I, myosin light chain 3) has been completed in these breeds and a mutation has not been associated with their disease. It is now hypothesized that a mutation in an additional sarcomeric gene, the alpha tropomyosin gene, is associated with the disease in the NWF, Sphynx, and Siberian cat. Additionally, it is hypothesized that a causative mutation in this gene will be identified in a few Ragdolls and Maine Coons. The objective of this study is to identify a causative mutation in the coding or splice site regions of the alpha tropomyosin gene in affected cats from these breeds.

[This project is approved pending funding from Norwegian Forest Cat, Sphynx, Siberian, Ragdoll, and Maine Coon breeders. This project is also supported by the Ricky Fund.]

BRIA FUND PROJECTS

#08-004: Molecular basis of feline coronavirus pathogenesis and development of FIP in cats
Gary R. Whittaker, PhD; Cornell University; $15,000

Feline infectious peritonitis (FIP) is a lethal systemic infection in cats, caused by feline coronavirus (FCoV). Infection by FCoV normally causes mild and often inapparent enteritis, in which case the virus is referred to as feline enteric coronavirus (FECV). In the "internal mutation" model of FIP, it is believed that a process of mutation within an individual cat confers the ability of FECV to infect macrophages, and so become feline infectious peritonitis virus (FIPV) - the virus that causes FIP. However, there has been little experimental support to date for the internal mutation theory of FIPV. This project hypothesizes that that mutation of the FECV spike protein results in changes in the processing of the spike protein by host cell proteases, which leads to acquisition of a hyperfusogenic spike protein and confers the ability of the virus to infect macrophages, and so initiate the process of FIP. The investigators will test this hypothesis by cloning the spike proteins of a range of feline coronaviruses, and performing site-directed mutagenesis followed by direct fusion assays, and incorporation of wild type and mutant spike proteins in pseudovirions. Fusion and entry will be monitored in feline epithelial cells and monocytes/macrophages in the presence of inhibitor proteases and endosomal pH, with the goal of determining the molecular changes that account for the acquisition of an FIP phenotype by the virus.

#08-006: Identification of the cellular receptor for feline coronaviruses
H.F. Egberink, DVM, PhD and P.J.M. Rottier, PhD; Utrecht University; $15,000

Feline coronaviruses (FCoVs) are common pathogens of domestic and wild Felidae. While generally occurring as almost harmless enteric viruses, occasionally these avirulent viruses - by mutations not identified yet - turn into the most devastating and dreaded feline pathogens known, the feline infectious peritonitis viruses (FIPVs).

FCoVs also occur in two serotypes, I and II - the ubiquitous 'real' feline coronaviruses (type I) and the rare hybrid viruses (type II). The latter arise sporadically by recombination between a type I virus and a canine coronavirus in a doubly infected host. Yet, essentially all we know about FCoVs comes from studies with these rare hybrid viruses, simply because a suitable cell culture system for the propagation of the true feline coronaviruses has not been established. The aim of this proposalis to develop such a system by identifying the type I FCoV receptor and stably expressing it in cells. This will enable the investigators to grow the true FCoVs and to study their infection, and finally make these pathogens accessible for research. Their approachwill be to synthesize, by expression in cell culture, the type I FCoV spike (S) protein, the receptor-binding moiety on the virus. This protein will be used as an affinity tool to recognize - in a lysate of feline intestinal cells, i.e. the natural FCoV target cells - the receptor, which will subsequently be identified by mass spectroscopy. The receptor gene will then be cloned and stably expressed in cells to create the cell line(s) susceptible to FCoV infection.

#08-036: Blood parameters potentially associated with susceptibility to feline coronavirus in Birman cats
Saverio Paltrinieri, DVM, PhD, DECVCP; University of Milan; $14,780

The purpose of this study is to identify possible breed-specific immunological patterns of Birman cats, potentially explaining their predisposition to develop feline infectious peritonitis (FIP). Many factors could be involved in resistance/susceptibility to the feline coronavirus (FCoV), which is responsible for FIP. Specifically, cats infected by FCoVs but not affected by FIP have lymphoid hyperplasia, increased number of lymphocyte subpopulations, transient increases and hypersyalilation of serum α1-acid glycoprotein (AGP), and increased levels of cytokines involved in cell-mediated immunity. By contrast, cats with FIP have lymphoid depletion both in lymph nodes and in blood, persistently increased and hyposyalilated serum AGP, and decreased levels of cytokines involved in cell-mediated immunity. The possible presence of these changes in Birman cats would help explain their relative susceptibility to FIP, thus allowing breeding strategies to select "resistant" cats.

NEW PROJECTS

#08-020: Mirtazapine as an Appetite Stimulant and Anti-nausea Therapy for Cats with Chronic Kidney Disease
Katharine F. Lunn, PhD, MRCVS, DACVIM; Colorado State University; $14,992

Chronic kidney disease (CKD) is common in geriatric cats. Clinical signs include polyuria, polydipsia, decreased appetite, weight loss and vomiting. Inappetence leads to negative energy balance with associated weight loss, muscle weakness, and poor quality of life. Several recent studies have documented the therapeutic value of specially formulated diets in the management of CKD. Therefore a key therapeutic target for these patients is the maintenance of appetite and food intake. Mirtazapine (Remeron®) was introduced to human medicine as an antidepressant. However it has recently attracted interest in veterinary medicine due to the presence of several desirable side-effects, namely its significant anti-nausea, anti-emetic, and appetite stimulating properties. Mirtazapine doses for cats have been extrapolated from human medicine; however no pharmacological studies have been reported in support of these extrapolations. In order to provide accurate dosing recommendations for maximal efficacy and to avoid side effects, it would therefore be prudent to investigate the pharmacokinetics of mirtazapine in cats. A prospective placebo-controlled study is also needed to assess the efficacy of the drug as an appetite stimulant and anti-emetic in cats with CKD. The expected outcome of this study is an understanding of the pharmacokinetics of mirtazapine in the normal cat, and how this is affected by age and renal impairment. The study will also document the efficacy of this drug as an appetite stimulant and anti-emetic in cats with CKD. The results of these studies will allow veterinarians to use evidence-based therapy in the management of feline CKD.

#08-027: Feline Squamous Cell Carcinoma: The Effects of 5-Lipoxygenase Inhibition and Prevalence of Upregulation
Joseph Wakshlag, DVM, PhD; Cornell University; $14,150

Feline squamous cell carcinoma accounts for approximately 6-8% of feline cancers afflicting approximately 50,000 cats in the United States every year. Despite more progressive treatments in oncology, there are few significant alternatives other than radiation treatment. Cyclooxygenase-2 metabolism of arachidonic acid has recently been identified in some oral feline squamous cell carcinomas and may play a role in progression or initiation of the disease. However, more recently rodent and human oral squamous cell carcinoma have shown that lipoxygenase (LOX) expression may play an equal, if not greater role in cancer invasiveness/progression. Additionally, the investigator's preliminary data suggests that LOX may be more important to cell proliferation and is over-expressed in oral feline squamous cell carcinoma. The expression of 5-LOX in feline tumors has yet to be characterized. However, there are non-steroidal dual inhibitors of COX-2 and 5-LOX available in the companion animal market that may be useful palliative treatment, particularly for oral squamous cell carcinoma. An extensive study into the role of 5-LOX in squamous cell carcinoma proliferation and progression, as well as its expression and activity in naturally occurring in feline squamous cell carcinoma is warranted, particularly due to the recent success of COX-2/5-LOX inhibitors in models of squamous cell carcinoma.

#08-028: Prostaglandin E2 Biosynthesis in Feline Mammary Cancers
Sakhila K. Banu, MSc, MPhil, PhD; Texas A&M University; $15,000

The objective of this project is to identify novel cell signaling pathways for chemotherapy for feline mammary cancers. Mammary neoplasia is a devastating disease in cats and accounts for 17% of neoplasms. Between 80 and 96% of feline mammary tumors are malignant. Currently, chemotherapeutic strategies are very limited because most of the tumorigenic pathways are unknown in feline. PGE2 plays a pro-oncogenic role in development of mammary cancers in various species. Cyclooxygenase-2 (COX-2) and Prostaglandin E-Synthase -1 (PGES-1) regulate biosynthesis of PGE2. High expression of COX-2/PGES-1 and increased production of PGE2 are considered to be hallmarks of mammary cancers. Epidermal growth factor receptor (EGFR)-mediated pathways regulate PGE2 production in metastatic cancers. Molecular and cellular aspects of PGE2 biosynthesis are not known in feline cancers. The investigators hypothesizethat PGE2 promotes mammary cancer development in cats. Their specific aimsare to: (1)Clone feline COX-2 and PGES-1 and to study their expression in feline mammary cancers in vivo; (2)Determine selective role of COX-2 and PGES-1 in feline mammary cancer cell proliferation and invasion in vitro; (3)Determine interactions between EGFR pathways and COX-2 and PGES-1 proteins in feline mammary cancers in vitro. By multidisciplinary collaborative approach, in vivo and in vitro systems will be used to achieve the specific aims. Completion of this proposed project will determine the role of PGE2 in feline mammary cancers. The critical pathways identified in this research project may lead to develop novel chemotherapeutic strategies for the treatment and/or prevention of mammary cancers in felines.

#08-030: The in vitro effects of histone deacetylase inhibitors on feline oral squamous cell carcinoma
William C. Kisseberth, DVM, PhD; The Ohio State University; $15,000

Oral squamous cell carcinoma (OSCC) is the third most common tumor in the cat and represents 61% of the tumors in the oral cavity. Generally, this devastating disease is recognized late in its course and quickly becomes debilitating with survival times around 3 months. The location of the tumor combined with the pain it causes prevents the cat from eating, swallowing or grooming. Although many types of chemotherapy along with radiation therapy have been used, there has been no improvement in quality of life or survival times for these cats. In an effort to improve upon these results, the investigators have chosen to investigate the in vitro effects of histone deacetylase (HDAC) inhibitors OSU-HDAC42 and suberoylanilide hydroxamic acid (SAHA) on feline OSCC cell lines (SCCF1, SCCF2 and SCCF3). These targeted therapies, which inhibit various cancer causing signaling pathways, have been tested on human head and neck SCC and canine cancer cell lines with promising results, such that several are now undergoing testing in clinical trials in both species. As a result, it is hypothesized that the HDAC inhibitors OSU-HDAC42 and SAHA will decrease viability of feline OSCC cells in vitro. As such, cells will be exposed to these therapies and those cells exhibiting significant antitumor effects will be characterized further in future studies. Ultimately, by studying the effects of these inhibitors on feline OSCC cell lines, the investigators hope to determine their efficacy against OSCC in cats as a way to improve survival.

#08-021: Safety and Bioavailability of Oral L-Arginine Supplementation in Cats with Naturally Occurring Chronic Renal Failure
Macon Miles, DVM; Animal Emergency Referral Center; Torrance, CA; $4,708

The proximal convoluted tubules of the kidney are the main site of synthesis of L-arginine from intestinal mucosa derived citrulline in cats. Unlike humans, dogs and rats, the amino acid L-arginine is an essential amino acid for cats due to a relative deficiency of enzymes for de novo citrulline synthesis by the intestinal mucosa. A previous study has shown that L-arginine levels are significantly reduced in cats with naturally occurring chronic renal failure. L-arginine is a substrate for nitrous oxide (NO) synthesis, a potent vasodilator. Nitrous oxide synthesis is decreased in animal models of renal failure and humans with chronic renal failure (CRF). This decrease in NO synthesis is believed to play a role in mediating hemodynamic changes associated with progression of renal disease. The investigators hypothesize that supplementation of oral L-arginine to cats with stage II and III chronic renal failure will decrease proteinuria and slow progression of disease, leading to prolonged survival. No studies have been conducted to determine the safety of oral supplementation of L-arginine in cats with CRF and whether oral supplementation can increase plasma arginine levels. In this study, L-arginine or a placebo will be supplemented for one month in 12 cats with naturally occurring CRF to evaluate whether oral supplementation will increase plasma L-arginine levels and whether the supplementation has any adverse effects on renal function. If safe and effective at increasing plasma arginine levels, then larger studies evaluating whether oral L-arginine supplementation can decrease proteinuria and improve survival are warranted.

[This study has been approved pending further funding. For information on how to donate to this study, please contact us.]



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