Objective: To investigate the influence of dietary supplementation with l-carnitine on metabolic rate, fatty acid oxidation, weight loss, and lean body mass (LBM) in overweight cats undergoing rapid weight reduction. Animals: 32 healthy adult neutered colony-housed cats. Procedures: Cats fattened through unrestricted ingestion of an energy-dense diet for 6 months were randomly assigned to 4 groups and fed a weight reduction diet supplemented with 0 (control), 50, 100, or 150 μg of carnitine/g of diet (unrestricted for 1 month, then restricted). Measurements included resting energy expenditure, respiratory quotient, daily energy expenditure, LBM, and fatty acid oxidation. Following weight loss, cats were allowed unrestricted feeding of the energy-dense diet to investigate weight gain after test diet cessation. Results: Median weekly weight loss in all groups was ≥ 1.3%, with no difference among groups in overall or cumulative percentage weight loss. During restricted feeding, the resting energy expenditure-to-LBM ratio was significantly higher in cats that received l-carnitine than in those that received the control diet. Respiratory quotient was significantly lower in each cat that received l-carnitine on day 42, compared with the value before the diet began, and in all cats that received l-carnitine, compared with the control group throughout restricted feeding. A significant increase in palmitate flux rate in cats fed the diet with 150 μg of carnitine/g relative to the flux rate in the control group on day 42 corresponded to significantly increased stoichiometric fat oxidation in the l-carnitine diet group (> 62% vs 14% for the control group). Weight gain (as high as 28%) was evident within 35 days after unrestricted feeding was reintroduced. Conclusions and Clinical Relevance: Dietary l-carnitine supplementation appeared to have a metabolic effect in overweight cats undergoing rapid weight loss that facilitated fatty acid oxidation.

This study investigated the effects of onion juice on the serum lipid components and blood pressure in obese rats fed high fat diets. Thirty-nine of Sprague-Dawley rats were divided into six groups, and were treated for 8 weeks: (1) normal diet (ND); (2) high fat diet (HFD); (3) HFD for first 4 weeks and high fat diet with 40% onion juice for the last 4weeks (H-H+O); (4) HFD with 40% onion juice for 8 weeks (H+O); (5) HFD for first 4 weeks and ND for the last 4 weeks (H-N); (6) HFD for first 4 weeks and ND with 40% onion juice for the last 4 weeks (H-N+O). The rates of increasing body weight were reduced in H+O and H-H+O groups compared with HFD group. The levels of triglyceride, low density lipoprotein-cholesterol and total cholesterol in blood serum were significantly decreased in the H+O and H-H+O groups compared with the HFD group. Administration of onion reduced the size of adipocyte, steatosis, and serum hyperlipidemia in obese rats fed HFD. Moreover, the antihypertensive effects of onion were observed in obesity rat fed HFD. Overall results suggest that onion reduces the serum lipid components and improves hypertension in obese rat fed HFD.

We examined the effect of stroma-derived factors, hepatocyte growth factor (HGF) and leptin, on morphological differentiation of bovine mammary epithelial cells (BMEC) in collagen gel three-dimensional culture in vitro. BMEC treated with HGF, but not leptin, formed duct-like organoids. The formation of organoids by HGF was enhanced by treatment with a mixture of insulin, cortisol and prolactin, while BMEC treated with the mixture alone did not produce the organoid. In contrast, the formation of organoids by HGF was dose-dependently inhibited by simultaneous addition of leptin, regardless of the presence or absence of the hormone mixture. These results suggest that stroma-derived factors intricately regulate mammary epithelial morphogenesis.