Evaluation of circulating extracellular vesicles and miRNA in neutered and obese female dogs.

Adipose tissue is a metabolic and endocrine organ, and its adipocytes can synthesize and secrete extracellular vesicles (EVs), thus allowing intercellular communication. EVs are nanoparticles that transport lipids, proteins, metabolites, and nucleic acids (mRNA and microRNAs). MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression. miR-132, miR-26b, and miR-155 are associated with obesity, lipid metabolism and adipogenesis. The aim of this study was to evaluate the enriched EVs fraction containing miRNAs (miR-132, miR-26b, and miR-155) in serum from obese female dogs. Thirty-two neutered females in good general condition were recruited, including 21 obese and 11 healthy controls. The initial evaluation of the females included a general physical examination and laboratory tests. Small EVs (sEVs) were isolated from whole blood by serial centrifugation and ultracentrifugation, and nanoparticle analysis was used to determine the size and concentration of serum sEVs. miRNAs were extracted from sEVs enriched fraction and analyzed by real-time polymerase chain reaction. Obese female dogs with hypertriglyceridemia showed an increase in the sEVs concentration and in the expression of miR-132 and miR-26b in sEVs enriched fraction. No changes were observed in the group of obese female dogs with normal serum biochemical profile and in relation to miR-155 expression. These results suggest that obese female dogs with hypertriglyceridemia may present alterations in sEVs and in the expression of miRNAs related to lipid metabolism and adipogenesis.

Tepoxalin on renal function and liver enzymes in cats exposed to hypotension with isoflurane / Tepoxalina sobre a função renal e as enzimas hepáticas em gatos submetidos à hipotensão com isofluorano

This study aimed to evaluate the possible renal and hepatic toxicity of tepoxalin administered before or after isoflurane-induced hypotension, as well as for five consecutive days. Twelve healthy mixed-breed cats, adult males, weighing 4.0±0.8kg were allocated into two groups. They received 25mgkg-1 of tepoxalin orally, two hours before the anesthetic procedure (PRE) or after the procedure (POST) and daily for five days. Cats were anesthetized with isoflurane and the concentration was increased until mean arterial pressure reached 40-60mmHg and kept at this level for 60 minutes. During hypotension, the physiological variables were measured at time 0 and every 10 minutes until 60 minutes, and bleeding time was measured at time 0, 30 and 60 minutes. Blood samples were drawn for a hemogram and determination of concentrations of alanine aminotransferase, alkaline phosphatase, urea, creatinine and Na+ at baseline, 24 hours, 48 hours and 7 days post-hypotension. Urine was collected at baseline, 24 hours, 48 hours and 7 days post-hypotension for determination of concentrations of creatinine, gamma-glutamyltransferase, urine specific gravity, protein, albumin and Na+. During the anesthetic procedure there were no important variations in physiological variables and bleeding time. There were differences only in fractional excretion of Na+, which was elevated at 7 days of evaluation in PRE and in the urine protein/creatinine ratio in PRE, which was higher than in POST at 24 and 48 hours post-hypotension. We conclude that tepoxalin does not cause alterations in hepatic enzymes but can cause discrete renal injury, resulting in proteinuria, in cats subjected to 60min of hypotension.

Este estudo teve como objetivo a avaliação da possível toxicidade renal e hepática da tepoxalina administrada antes ou após hipotensão induzida por isofluorano, assim como a sua administração nos cinco dias seguintes à hipotensão. 12 gatos adultos hígidos, machos, sem raça definida e com peso de 4,0±0,8kg foram alocados em dois grupos (n=6). Os animais receberam 25mgkg-1 de tepoxalina pela via oral, duas horas antes do procedimento anestésico (PRE) ou após o procedimento (POST) e diariamente por cinco dias consecutivos. Os gatos foram anestesiados com isofluorano, aumentando-se a sua concentração até que se atingisse uma pressão arterial média entre 40 e 60mmHg, sendo mantida durante 60 minutos. Durante o procedimento de hipotensão, os parâmetros fisiológicos foram mensurados no tempo 0 e a cada dez minutos até o fim do procedimento. O tempo de sangramento da mucosa oral foi avaliado no tempo 0 e aos 30 e 60 minutos de hipotensão. Amostras sanguíneas foram colhidas para a determinação de hemograma, alanina aminotransferase, fosfatase alcalina, ureia, creatinina e sódio no período basal e às 24 horas, 48 horas e sete dias pós-hipotensão. Amostras de urina foram colhidas por meio de cistocentese para a determinação de creatinina, gammaglutamiltransferase, densidade específica, proteínas, albumina e sódio. Durante o período anestésico, não ocorreram alterações referentes aos parâmetros fisiológicos e ao tempo de sangramento. Ocorreram alterações apenas na excreção fracionada de sódio, a qual demonstrou elevação no PRE aos sete dias, e na razão proteína/creatinina na urina, a qual demonstrou elevação do PRE em relação ao POST às 24 e às 48 horas de avaliação. Concluiu-se que a tepoxalina não causou alterações nas enzimas hepáticas, mas pode causar discreta injúria renal, com a presença de proteinúria, em gatos que foram submetidos à hipotensão.