Even a little is too much:A longitudinal study of weight gain in the cat

Oxidative stress;Inflammatory response;Obesity;Insulin sensitivity;Insulin resistance

Pach, Nicole M. ; Hoenig ; Margarethe

关键词: Oxidative stress;    Inflammatory response;    Obesity;    Insulin sensitivity;    Insulin resistance;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/18597/Pach_Nicole.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Obesity and insulin resistance has increased in the last three decades among humans and cats and has been associated with an increase in the inflammatory response and oxidative stress in people.The purpose of this study was to determine if an increase in fat mass was associated with an increased inflammatory response and oxidative stress, leading to insulin resistance and abnormal insulin secretion.Twenty cats of equal gender distribution were used for the study; 10 were fed a control diet (C) and 10 were fed the same diet containing an antioxidant mixture (AOX). The following parameters were measured at 0%, 10%. 30% and 60% weight increase: body mass index (BMI), girth, total fat, food intake, glucose and insulin concentrations before and after an intravenous glucose tolerance test, baseline cholesterol, HDL, triglyceride, non-esterified fatty acids (NEFAs), catalase, glutathione peroxidase, superoxide dismutase, interleukin-6 (IL-6), Interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-alpha), respiratory exchange ration (RER), and heat production.Body mass index (BMI), girth, total fat, and energy intake increased significantly with increasing body weight.There was no difference in glucose baseline concentrations as a result of body weight increase.However, at 60% body weight increase the AUC for glucose increased significantly in cats fed AOX, indicating glucose intolerance.A significant decrease was seen in insulin sensitivity with increasing body weight.Baseline insulin concentrations and total AUC increased significantly with increasing body weight, BMI and girth indicating insulin resistance even at a 10% body weight increase.Triglycerides and NEFAs increased significantly with increasing body weight, indicating a possible increase in VLDL and a decrease in lipoprotein lipase.The enzyme activity of catalase, glutathione peroxidase, and superoxide dismutase did not change significantly with increasing body weight, indicating a lack of oxidative stress.The cytokines IL-6, IL-1, and TNF-alpha did not change significantly with increasing body weight, indicating no inflammatory response with increasing body weight.The RER increased significantly at 30 and 60% body weight increase, indicating a decrease in fat oxidation.A significant increase in heat production with increasing body weight was seen, indicating increased energy production, likely due to the increase in food intake. In conclusion, an increase in obesity does not elicit an inflammatory response in cats, despite the fact that it leads to insulin resistance even at a 10% body weight increase.These results may in part explain the fact that obese cats do no exhibit atherosclerosis, hypertension or other signs of the metabolic syndrome observed in obese human subjects.