Adipose gene expression related to body condition score and individual variations in hospitalized cats

Obesity is a risk factor for various diseases. The prevalence of obesity is increasing in cats. The present study aimed to characterize adipose gene expression to obtain basic information for obesity prevention in feline adipose tissues. Visceral fat, subcutaneous fat, or both fat depots were collected from 81 hospitalized cats. The multivariate analysis of covariance revealed that sex and IGF-1 were involved in regulating body condition score (BCS), showing adiposity in both fat depots. BCS was positively and negatively regulated by expression levels of inflammation-related genes in visceral fat, respectively. In addition, subcutaneous Lep expression positively regulated BCS. Positive correlations between gene expression levels were generally detected within the same fat depot, whereas expression levels of genes in visceral fat were less related to those in subcutaneous fat, except for the same gene. Expression levels of Ucp1 were most variable among individuals in visceral fat but not in subcutaneous fat. The extent of individual variability on expression levels in cats was similar to that in the previous results using dogs. Genes related to mitochondrial respiration and uncoupling were relatively variable among individuals. The present study suggests that feline energy metabolism in adipose tissues is finely tuned in a fat depot-dependent manner. In addition, genes related to mitochondrial respiration and uncoupling may be a target for the control of systemic energy status because they can be potentially regulated by every individual.