CARDIOVASCULAR PROTEOMICS AND MITRAL VALVE DISEASE IN DOGS: SEARCHING FOR A SEROLOGICAL BIOMARKER

CARDIOVASCULAR PROTEOMICS AND MITRAL VALVE DISEASE IN DOGS: SEARCHING FOR A SEROLOGICAL BIOMARKER Myxomatous valve disease (MVD) is the most common heart valvular disease in humans in Europe and United States, and it\u2019s the primary naturally occurring heart disease in dogs. MVD is pathologically identical in humans and dogs, suggesting a common pathogenesis in these species, and creating an increasing interest in the canine MVD as a model for the human medicine. Nowadays, MVD is one of the most studied CVDs, because of its high prevalence in the clinical practice. Thanks to the research efforts, great diagnostic and therapeutic progresses have been made in the last decades, and continuous improvement are in the making. In recent years, new technologies have been used by the cardiovascular medicine, and the advancement of proteomic techniques has improved the methods available for investigating CVDs. Proteomics is the large-scale study of proteins and its application to uncover the protein function and structure in normal or disease states in the cardiovascular field is called cardiovascular proteomics. Even if the use of cardiovascular biomarkers is widespread in both human and veterinary medicine, the application of cardiovascular proteomics to the MVD study has recently begun. In the present study we selected a cohort of private-owned dogs recruited from the Cardiologic Service of the Department of Veterinary Science and Public Health. The dogs were selected with precise inclusion and exclusion criteria. Two breeds were considered: Cirneco dell\u2019Etna and Cavalier King Charles Spaniels. The Cirneco dell\u2019Etna breed is a poorly diffuse Italian hunting breed whose CVDs prevalence has never been studied before, while the Cavalier King Charles Spaniel breed is the most studied breed for all the MVD researches, because of the high prevalence of MVD, the early onset and the strong scientifically proved hereditary component. The objective of the present study was to search one or more than one serological biomarkers in dogs affected by MVD, comparing blood samples from the healthy dogs of the groups with blood samples from the dogs affected by different stages of MVD. The proteomics results were then matched with the clinical and echocardiographic data obtained in the clinical trial of all the patients included in the study, to find a connection available in the clinical practice. 64% of the Cirneco dell\u2019Etna dogs included in the study were affected by MVD, and all the dogs older than 6 years had echocardiographic signs of MVD. The proteomic analysis of the Cirneco samples gave the following results: the alpha-1-antytripsina (A1AT) was up-regulated in the patients affected by MVD, according to the severity of the pathology, while the complement C3 was down-regulated with the development of MVD, according to the stage of the disease. Among the Cavalier King Charles breed there was a high prevalence of MVD (63%) and a very low medium age of onset (4 years). The proteomic analysis of the Cavalier King Charles Spaniel samples produced the following results: the serum albumin was down-regulated, according to the severity of the pathology, while it was observed a strong up-regulation of some specific types of IgG and IgM, according to the severity of the pathology. Based on our study results, the Cirneco dell\u2019Etna breed is a primitive hunting breed predisposed to the development of MVD, with an early onset of the pathology. All the CdE dogs older than 6 years should be therefore evaluated for MVD, and included in a screening program. We confirmed that Cavalier King Charles Spaniel is a breed with a high prevalence of MVD and an early onset too, as previously reported. The proteomic analysis conducted on our samples and correlated to the clinical results, indicate that the MVD is a pathology that is strictly connected to a chronic inflammation state. The up-regulation of A1AT, IgG, IgM, and the down-regulation of complement C3 and serum albumin are connected with an inflammatory status, that cause a depletion of the components of the complement system, an activation of the acute phase proteins and of the components of immunity response like IgG and IgM immunoglobulins. The hypothesis that MVD could be related to a chronic inflammation was already speculated in the last years, and, based on the present study results, we think that the analysis of the inflammatory mediators in MVD patients could be a great chance to uncover the pathogenic mechanism at the base of mitral valve disease

Le cardiomiopatie secondarie nel gatto : quando l\u2019ipertrofia non dipende dal cuore

Feline hypertrophic cardiomyopathy is the most common acquired heart disease seen in felines. Hypertrophic cardiomyopathy is a term used when there is no known cause, however secondary, is brought about by other conditions such as high blood pressure, hyperthyroidism etc. Cats with secondary hypertrophic cardiomyopathy tend to be older than cats affected by HCM, the cardiac alterations as excessive thickening of the left ventricular wall, papillary muscles and septum detected by echocardiographic examination and other clinical symptoms tend to have resolution after appropriated therapy of hyperthyroidism and systemic hypertension

Serum creatinine and urine protein : creatinine ratio in dogs affected by myxomatous mitral valve disease

Cardiac disease is often associated with worsening renal function, in humans. The cardiorenal syndromes (CRS) were defined as disorders of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other. Five subtypes of the syndromes were identified; of these, CRS 2 indicates chronic abnormalities in cardiac function causing progressive and potentially permanent chronic kidney disease. Recent investigations support the role of central venous congestion, neurohormonal activation, anemia, oxidative stress and renal sympathetic activity as potential contributors to this complex syndrome. The main marker of kidney\u2019s disease in humans is considered the glomerular filtration rate. However, serum creatinine (sCr) and urine protein:creatinine ratio (UPC) are recognized as predictors of worsening renal function as well. The aim of this study was to investigate renal function in dogs with myxomatous mitral valve disease (MMVD) and cardiac remodeling (ACVIM stage 65B2) by measurement of sCr and UPC. This is an observational case-control study. Twenty dogs of various breeds, aged 7-15 years, affected by MMVD with hemodynamically signi\ufb01cant mitral regurgitation and cardiac remodeling (left ventricle internal diameter in diastole normalized according to allometric scaling 65 1.7 and/or LA/Ao ratio 65 1.6) were included in the study. Twenty healthy dogs of various breeds, aged 7-15 years were included as controls. Dogs with congenital or acquired cardiac disease other than MMVD, dogs with previous history or clinical signs at presentation of systemic, inflammatory or infectious disease, malignancies, hypertension (systolic blood pressure >160mmHg) or evidence of other organ dysfunction or hyperthermia were not included in the study. On each dog physical examination, echocardiography, ECG, RX, systemic blood pressure measurement, blood and urine analysis were performed in order to obtain a classification of MMVD (ACVIM consensus statement 2009) and chronic kidney disease (IRIS classification). Both dogs with MMDV and controls resulted IRIS class 1. The study revealed no statistically significant difference in sCr and UPC between dogs with MMVD (sCr: 0.76 mg/dl, 0.41 \u2013 1.21; UPC: 0.26, 0.00 \u2013 1.03) (mean; range) and controls (sCr: 0.74 mg/dl, 0.37 \u2013 1.21; UPC: 0.21, 0.03 \u2013 0.98) (mean; range). These results suggest that hemodynamically signi\ufb01cant mitral regurgitation with cardiac remodeling and expected neurohormonal system activation do not affect proteinuria and renal function. Nevertheless further studies are needed to confirm these findings

Retrospective investigation on the prevalence of pulmonary hypertension in dogs with bronchial and upper respiratory diseases

Bronchial and upper respiratory diseases have been associated with hypoxia and subsequent development of pulmonary arterial hypertension (PAH). However, there are no known studies assessing the prevalence of PAH in dogs with these conditions. The aim of this study was to assess the frequency of PAH in dogs with bronchial and upper respiratory diseases. Medical records of dogs with confirmed diagnosis (by endoscopic examination) of bronchial and/or upper respiratory diseases referred for cardiovascular investigation (January 2009 - May 2013) were retrospectively reviewed. Diagnosis of PAH was made by echocardiography (tricuspid regurgitation >2.8 m/s and/or pulmonic regurgitation >2.2 m/s); possible PAH was diagnosed when two or more specific echocardiographic findings were present. 52 dogs (30 with upper respiratory diseases, 17 with bronchial disease and 5 with both) were included. Diagnosis of PAH was performed in 3 dogs (5.7%). Two dogs were considered as probably affected by PAH; a total of 5 dogs (9.4%) resulted in being affected or probably affected by PAH. Our study shows that the prevalence of PAH in dogs with bronchial and/or upper respiratory diseases is low; PAH seems to occur mostly in older dogs and/or with very advanced disease: echocardiography may therefore be a useful tool in this category of patients

Serum proteomic profiles in CKCS with Mitral valve disease

Background: Myxomatous mitral valve disease (MVD) is the most common acquired heart disease in dogs, and the Cavalier King Charles Spaniel (CKCS) is the most studied breed because of the high prevalence, early onset and hereditary component evidenced in the breed. MVD has different severity levels, and there are many practical limitations in identifying its asymptomatic stages. Proteomic techniques are valuable for studying the proteins and peptides involved in cardiovascular diseases, including the period prior to the clinical onset of the disease. The aim of this study was to identify the serum proteins that were differentially expressed in healthy CKCS and those affected by MVD in mild to severe stages. Proteomics analysis was performed using two-dimensional gel electrophoresis separation and a bioinformatics analysis for the detection of differentially expressed spots. In a comparative analysis, protein spots with a p<0.05 (ANOVA) were considered statistically significant and were excised from the gels for analysis by MALDI-TOF-MS for protein identification. Results: Eight proteins resulted differentially expressed among the groups and significantly related to the progression of the disease. In mild affected group versus healthy dogs complement factor H isoform 2, inhibitor of carbonic anhydrase, hemopexin, dystrobrevin beta isoform X7 and CD5 molecule-like resulted to be down-regulated, whereas fibronectin type-III domain-containing protein 3A isoform X4 was up-regulated. In severe affected dogs versus healthy group complement factor H isoform 2, calpain-3 isoform X2, dystrobrevin beta isoform X7, CD5 molecule-like and l-2-hydroxyglutarate dehydrogenase resulted to be down-regulated. Complement factor H isoform 2, calpain-3 isoform X2, dystrobrevin beta isoform X7, CD5 molecule-like and hydroxyglutarate dehydrogenase were found to be down-regulated in mild affected group versus healthy dogs. All of these proteins except complement factor H followed a decreasing trend according to the progression of the pathology. Conclusion: The differential expression of serum proteins demonstrates the possibility these might be valuable for the detection and monitoring of the disease. Further longitudinal studies are required to determine whether differential protein expression occurs sufficiently early in the progression of the disease and with sufficient predictive value to allow proteomics analysis to be used as an early detection and on-line diagnostic tool

Feline cardiomyopathies: a survival study

Feline cardiomyopathies (CM) represent an heterogeneous group of myocardial disease. Idiopathic Hypertrophic cardiomyopathy (HCM) is the most common CM in cats, characterized by an hypertrophied left ventricle in the absence of concurrent diseases responsible to increase myocardial mass. The second most common CM in cats is restrictive cardiomyopathy (RCM), identified by biatrial enlargement, stiff left ventricle in the absence of marked LV hypertrophy. Secondary CM due to hyperthyroidism and systemic hypertension are frequent as well. Aim of this retrospective study was to compare survival and prognostic factors in cats affected by HCM, RCM or secondary CM referred in our institution over a 10 year period. The study included 101 cats with complete case record and echocardiographic exam. 54 cats presented HCM, 16 RCM and 30 secondary CM ( 12 cats were diagnosed with hyperthyroidism, while 18 cats presented BP > 170mmHg). A statistically significant different survival time was identified for HCM (mean survival time of 578days), RCM (466days) and secondary CM (643 days). In the overall population, risk factors in the multivariate analysis, regardless of the CM considered, were : presence of symptoms ( OR 4,07, p<0.004), an increased LA/Ao ratio ( OR 30.1, p<0.001) and presence of LA thrombi/smoke effect ( OR 4.7, p<0.003). Univariate analysis and multivariate analysis was carried on in HCM +RCM population. Univariate analysis identified RCM (OR 2.69, p2.5 vs normal LA/Ao( OR 58.69, p<0.001),presence of LA thrombi/ smoke effect ( OR 11.2, p<0.001) as risk factors for cardiac death. Multivariate analysis identified only LA/Ao >2.5 vs normal LA/Ao ( OR 45.06, p<0.001) and LA thrombi/smoke effect ( OR 5.6, p<0.003) as risk factors for cardiac related death. In conclusion, HCM and RCM are two distinct CM with different echocardiographic presentation, evolution over time, but they share some common features ( i.e. LA dimension and hyperviscosity syndrome) linked to feline cardiovascular physiology, which influence greatly survival in end-stage CM. Secondary CM are more benign conditions, but if the primary disease is not properly managed, prognosis might be poor also in this patients

Pulmonary hypertension associated with Ehrlichia canis infection in a dog

CANINE monocytic ehrlichiosis (CME) is an important canine disease with a worldwide distribution. The clinical presentation can be acute, subclinical or chronic, and there may be a multitude of clinical manifestations (Neer 1998, Neer and others 2002, Cohn 2003, Harrus and Waner 2011). This report describes a case of severe pulmonary hypertension (PH) in a dog infected with Ehrlichia canis, which completely resolved after treatment