Cardiac structural and functional findings in Persian cats with autosomal dominant polycystic kidney disease / Achados estruturais e funcionais cardíacos em gatos persas com doença renal policística autossômica dominante

ABSTRACT: Autosomal dominant polycystic kidney disease (ADPKD) has been related to left ventricular structural and functional abnormalities in human patients. The present study aimed to evaluate the cardiac structural and functional findings in Persian cats with ADPKD. Client-owned ADPKD (n=12) and non-ADPKD (n=12) Persian cats were enrolled in this study. The animals underwent echo- and electrocardiographic (ECG) examinations, and non-invasive measurements of systolic blood pressure (SBP) were obtained. Both groups were similar regarding hematological and biochemical parameters, including white blood cell count and levels of blood urea nitrogen, creatinine, total protein and thyroxine. There were no differences related to ECG parameters between ADPKD and non-ADPKD cats. Left ventricular hypertrophy (LVH) was demonstrated in 6/12 (50%) normotensive ADPKD cats with preserved renal function. There were no differences between animal groups regarding the echocardiographic parameters, including left ventricular ejection fraction and shortening fraction; however, basal interventricular septal thickness at end-diastole near the left ventricular outflow tract and aortic artery flow velocity showed slightly elevated values in ADPKD-cats. Our study revealed that Persian cats with ADPKD do not reproduce the functional and structural cardiac phenotype reported in human patients; however, large-scale cohort studies are necessary to distinguish the possibilities of a true linkage between ventricular myocardial hypertrophy and ADPKD in this breed.

RESUMO: A doença renal policística autossômica dominante (DRPAD) tem sido relacionada a anormalidades estruturais e funcionais de ventrículo esquerdo em pacientes humanos. O objetivo do presente estudo foi avaliar os achados estruturais e funcionais cardíacos em gatos persas com DRPAD. Gatos persas pertencentes à clientes com DRPAD (n=12) e sem DRPAD (n=12) foram envolvidos neste trabalho. Os animais foram submetidos aos exames de eco e eletrocardiografia (ECG) e foram obtidas medições não-invasivas da pressão arterial sistólica (PAS). Ambos os grupos apresentaram valores semelhantes em relação aos parâmetros hematológicos e bioquímicos, incluindo contagem de glóbulos brancos e níveis séricos de ureia, creatinina, proteína total e tiroxina. Não houve diferença em relação aos parâmetros do ECG entre os gatos com ou sem DRPAD. A hipertrofia ventricular esquerda foi demonstrada em 6/12 (50%) dos gatos normotensos com DRPAD e função renal preservada. Não houve diferenças entre os grupos em relação aos parâmetros ecocardiográficos, incluindo fração de ejeção e fração de encurtamento do ventrículo esquerdo, entretanto a espessura septal interventricular basal na diástole na via de saída do ventrículo esquerdo e a velocidade do fluxo da artéria aórtica mostraram valores ligeiramente elevados em gatos com DRPAD. Nosso estudo revelou que gatos persas com DRPAD não reproduzem o fenótipo cardíaco funcional e estrutural encontrado em pacientes humanos. No entanto, estudos de coorte em larga escala são necessários para distinguir as possibilidades de uma verdadeira ligação entre a hipertrofia ventricular do miocárdio e a DRPAD nesta raça.

Differential circulating concentrations of adipokines, glucagon and adropin in a clinical population of lean, overweight and diabetic cats.

BACKGROUND: Dyslipidemia, dysregulated adipokine secretion and alteration in glucagon and adropin concentrations are important obesity-related factors in the pathophysiology of human Type 2 diabetes; however, their roles in the pathophysiology of feline diabetes mellitus are relatively unknown. Here, we determined the concentrations of circulating leptin, adiponectin, pro-inflammatory cytokines, glucagon, adropin, triglycerides, and cholesterol, in non-diabetic lean and overweight cats and newly diagnosed diabetic cats. Client-owned cats were recruited and assigned into 3 study groups: lean, overweight and diabetic. Fasting blood samples were analyzed in lean, overweight and diabetic cats at baseline and 4 weeks after consumption of high protein/low carbohydrate standardized diet. RESULTS: Serum concentrations of triglycerides were greater in diabetics at baseline and were increased in both diabetic and overweight cats at 4 weeks. Plasma leptin concentrations were greater in diabetic and overweight at baseline and 4 weeks, whereas adiponectin was lower in diabetics compared to lean and overweight cats at baseline and 4 weeks. Diabetics had greater baseline plasma glucagon concentrations compared to lean, lower adropin than overweight at 4 weeks, and lower IL-12 concentrations at 4 weeks than baseline. CONCLUSIONS: Our results suggest that feline obesity and diabetes mellitus are characterized by hypertriglyceridemia and hyperleptinemia; however, diabetic cats have significantly lower adiponectin and adropin compared to overweight cats. Thus, despite having similar body condition, overweight and diabetic cats have differential circulating concentrations of adiponectin and adropin.

Congenital hepatic fibrosis and polycystic kidney disease not linked to C >A mutation in exon 29 of PKD1 in a Persian cat.

CASE SUMMARY: We describe the case of a 1-year-old male Persian cat diagnosed with congenital hepatic fibrosis (CHF) associated with renal polycystic disease and, for the first time, we have shown that there was no C >A mutation in exon 29 of PKD1 (polycystic kidney disease 1). The cat presented with a history of chronic weight loss, anorexia, vomiting, depression and lethargy, with profuse salivation and ascites on clinical examination. A mild elevation in liver-associated plasma enzymes suggested a hepatic disease. Owing to the cat's deteriorating condition, it was euthanized. During necropsy, the liver was found to be enlarged, firm and reddish, and the kidney had multiple small cortical cysts. Immunohistochemistry revealed that bile duct cells and epithelial cells of renal cysts showed positive immunoreactivity to keratin 19. Collagen fibers surrounding bile ducts within portal areas demonstrated reactivity to type IV collagen antibody, confirming the congenital nature of the process. A diagnosis of ductal plate malformation consistent with CHF associated with polycystic kidney in a young Persian cat was made. Interestingly, genetic testing revealed a wild-type sequence at position 3284 in exon 29 of PKD1. RELEVANCE AND NOVEL INFORMATION: The absence of the classic genetic mutation associated with the particular clinical presentation supports the hypothesis of a distinct etiopathogenesis among fibropolycystic diseases in domestic cats. Moreover, congenital hepatic fibrosis is a rare but important differential diagnosis for young Persian cats and their crosses with clinical signs of chronic end-stage liver disease.