Effects of dynamic feeding low- and high-methionine diets on the variation of glucose and lipid metabolism-related genes in the liver of laying hens.

We examined the effects of dynamic feeding low- and high-methionine diets on the transcriptional level of glucose and lipid metabolism-related genes in the liver of laying hens. A total of 180 laying hens (Brown Hy-line, 41 wk old) were exposed to 16 h of light and 8 h of darkness with lights on at 06:00 h local time (Zeitgeber time [ZT] 0) and allocated into 3 equal groups with 6 replicates. The control group was fed a 0.30% methionine diet. The low-high (LH) group was fed 0.27% methionine diet at ZT1.5 and 0.33% methionine diet at ZT8.5. The feeding regime in high-low (HL) group was opposite to that of the LH group. After 10 wk, a total of 108 hens (6 hens/group/time point) were randomly and equally selected for further analysis. Blood and liver tissues were collected at ZT21.5, ZT1.5, ZT5.5, ZT9.5, ZT13.5, and ZT17.5. The results showed that the serum ALP activity in the HL group was the highest at ZT9.5 and ZT13.5, and that the serum glucose content in the HL group was lowest at ZT21.5 compared to the other 2 groups (P < 0.05). The mesors, amplitudes, and acrophases of the cosine curves for the CLOCK, BMAL1, CRY1, PER2, and PER3 genes were altered in the LH and HL groups. G6PC3, PCK2, GPAT, INSIG2, FASN, ACACA, ACOX1, HMGCR, LDLR, and PPARA expression in the liver were affected by the feeding regime at some time point (P < 0.05). Two-way analysis of variance comparisons showed some significant effects of time on the mRNA expression of G6PC3, G6PC2, PCK2, FBP1, FBP2, GCK, GYS2, FASN, GPAT, HMGCR, LDLR, ACC, SREBP2, and INSIG1 (P < 0.05). Moreover, different feeding regimes significantly affected the expression of FASN, GPAT, HMGCR, LDLR, ACACA, SREBP1, and INSIG1 (P < 0.05). In conclusion, dynamical feeding low- and high-methionine diets affected the variation of serum ALP and glucose levels, as well as the mRNA expression of circadian clock- and glucose and lipid metabolism-related genes in the liver of laying hens.