An high dose of a conjugated linoleic acid increases fatty liver and insulin resistance in lactating mice

This study aimed to evaluate the effect of a high dose of conjugated linoleic acid (CLA) on lactating mice. In experiment one, KUNMING mice were separated into four groups (n = 6 per group); the control (CON) group received 3.0% linoleic acid oil (LA), the L-CLA group received 1.0% LA and 2.0% CLA mixture, the M-CLA group received 2.0% LA and 1.0% CLA mixture, and the H-CLA group received 3.0% CLA mixture. Feeding proceeded from day 4 to day 10 during lactation. In experiment two, the CON group received 2.0% LA and the H-CLA group received 2.0% CLA. Blood parameters were analysed for all groups, and insulin tolerance tests (ITTs) were conducted. CLA treatment did not affect the dam weight, but it significantly decreased the food intake of dams. Furthermore, CLA decreased the weight of pups, which was attributed to lower milk fat. H-CLA group mice displayed increased liver weight and liver triglyceride content, as well as a higher TG content and γ-GT activity in blood. Moreover, a high dose of CLA resulted in insulin resistance, possibly affecting the RBC and HCB of blood. In conclusion, lactating mice receiving a high dose of CLA led to fatty liver, insulin resistance, and impaired lactation performance.