Serum Lipid, Amino Acid and Acylcarnitine Profiles of Obese Cats Supplemented with Dietary Choline and Fed to Maintenance Energy Requirements

Abstract

Obesity is a health concern for domestic cats. Obesity and severe energy restriction predispose cats to feline hepatic lipidosis. As choline is linked to lipid metabolism, we hypothesized that dietary choline supplementation would assist in reducing hepatic fat through increased lipoprotein transport and fatty acid oxidation. Twelve obese cats (body condition score [BCS] ≥ 8/9) were split into two groups. Cats were fed a control (n = 6; 4587 mg choline/kg dry matter [DM]) or a high choline diet (n = 6; 18,957 mg choline/kg DM) for 5 weeks, for adult maintenance. On days 0 and 35, fasted blood was collected, and the body composition was assessed. Serum lipoprotein and biochemistry profiles, plasma amino acids and plasma acylcarnitines were analyzed. The body weight, BCS and body composition were unaffected (p > 0.05). Choline increased the serum cholesterol, triacylglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol and plasma methionine (p < 0.05) and decreased the serum blood urea nitrogen and alkaline phosphatase (p < 0.05). Choline also reduced the plasma acylcarnitine to free carnitine ratio (p = 0.006). Choline may assist in eliminating hepatic fat through increased fat mobilization and enhanced methionine recycling.

Dietary choline in gonadectomized kittens improved food intake and body composition but not satiety, serum lipids, or energy expenditure

“…This higher hepatic storage may require an increase in VLDL mobilization with PC. Therefore, this may account for the observed increase in VLDL levels in obese adult cats in the study by Verbrugghe et al [ 24 ].…”

“…Future studies should aim to assess choline supplementation during a controlled FI period. While the current study used a dose based on previous research of a dose response study of choline in rats [ 39 ] and in growing pigs [ 40 ], as well as a preliminary study in obese cats [ 24 ], a thorough dose response study in growing kittens and adult cats is also needed. Current choline requirements for kittens and adult cats were established via choline deficiency studies, not empirical measures of the requirement using a dose response approach, and evaluating liver lipid content [ 16 , 18 ].…”

“…Individual daily choline doses were provided for each cat at 300 mg choline/kg BW 0.75 and the appropriate amount was pipetted. This dose is based on previous research of a dose response study of choline in rats [ 39 ], and in growing pigs [ 40 ], as well as a preliminary study in obese adult cats [ 24 ]. The supplementation group was provided a small portion of food (20 g) with added choline solution prior to the 0800 h feeding times while the base diet group was provided the base diet only.…”

“…Due to this role of choline, deficiency is a known factor in developing non-alcoholic fatty liver in many species, including cats [ 16 ]. In obese cats fed to maintain body weight, choline supplementation at 5.1 times the NRC [ 19 ] recommended allowance resulted in increased blood CHOL, TAG, and VLDL which could indicate increased mobilization from the liver [ 24 ].…”

Circulating direct infusion MS and NMR metabolomic profiles of post-gonadectomy kittens with or without additional dietary choline supplementation

“…These metabolites have been classified by their metabolic pathways according to the Human Metabolite Database (44) : gluconeogenic amino acids; ketogenic amino acids; augmented amino acid degradation products; glycolysis; lipolysis; TCA cycle; ketogenesis; one-carbon metabolism; purine degradation; alcohols; and 'other'. Serum (100 uL) was used for Di-MS to analyze metabolites, which have been classified as: amino acids, amino acid derivatives, and ammonium compounds; biogenic amines; organic acids and sugars; acyl carnitines; PC; LPC; and sphingomyelins using a 4000 QTrap mass spectrometer (TMIC, University of Alberta, Edmonton, AB, Canada) (39) . Total amino acids were calculated as the sum of all presented amino acids.…”