The effects of dietary macronutrient composition on lipid metabolism-associated factor gene expression in the adipose tissue of chickens are influenced by fasting and refeeding

Abstract

BackgroundBroiler chickens are compulsive feeders that become obese as juveniles and are thus a unique model for metabolic disorders in humans. However, little is known about the relationship between dietary composition, fasting and refeeding and adipose tissue physiology in chicks. Our objective was to determine how dietary macronutrient composition and fasting and refeeding affect chick adipose physiology during the early post-hatch period.MethodsChicks were fed one of three isocaloric diets after hatch: high-carbohydrate (HC; control), high-fat (HF; 30% of ME from soybean oil) or high-protein (HP; 25% vs. 22% crude protein). At 4 days post-hatch, chicks were fed (continuous ad libitum access to food), fasted (3 h food withdrawal), or refed (fasted for 3 h and refed for 1 h). Subcutaneous, clavicular, and abdominal adipose tissue was collected for histological analysis and to measure gene expression, and plasma to measure non-esterified fatty acid (NEFA) concentrations (n = 6–10 per group).ResultsAdipose tissue weights were reduced in chicks that were fed the HP diet and adipocyte diameter was greater in the adipose tissue of chicks that ate the HF diet. Consumption of diets differing in protein and fat content also affected gene expression; mRNAs encoding fatty acid binding protein 4 and a lipolytic enzyme, monoglyceride lipase, were greater in chicks fed the HC and HF than HP diet in all three adipose tissue depots. Fasting influenced gene expression in a depot-dependent manner, where most fasting and refeeding-induced changes were observed in the clavicular fat of chicks that consumed the HC diet. Fasting increased plasma NEFA concentrations in chicks fed the HC and HP diets.ConclusionsThe decreased adipose tissue deposition in chicks fed the HP diet is likely explained by decreased rates of adipogenesis. Consumption of the HF diet was associated with greater adipose tissue deposition and larger adipocytes, likely as a result of greater rates of adipocyte hypertrophy. The depot-dependent effects of diet and fasting on gene expression may help explain mechanisms underlying metabolic distinctions among subcutaneous and visceral fat depots in humans.

Role of Corticosterone in Lipid Metabolism in Broiler Chick White Adipose Tissue

“…Similar results have been reported in 10- (Honda et al 2017) and 13-day-old chicks (Saneyasu et al 2013b). However, Wang et al (2017) reported that 3 h of fasting significantly reduced mRNA levels of ATGL in clavicular fat in 4-day-old broiler chicks fed a high-carbohydrate diet. One possible explanation is that the decrease in mRNA levels of ATGL may result from the suppression of adipocyte differentiation.…”

Lipid metabolism, fatty acid composition and meat quality in broilers supplemented with increasing levels of defrosted black soldier fly larvae

“…Plasma triglycerides concentrations increased linearly with increasing levels of BSFL intake, whereas a higher plasma NEFA concentration in L30 compared to L10 and the CON groups was observed. High plasma NEFA concentrations in the L30 group can be explained by either a high lipolysis rate due to a low dietary energy intake or a high intake of dietary fat (Wang et al, 2017a). Birds of the L30 group showed a lower ME intake which might be associated to higher plasma NEFA levels.…”

Transcriptome profile analysis of leg muscle tissues between slow- and fast-growing chickens

“…The results showed that the mRNA level of AGPAT9 was higher in the subcutaneous adipose tissue of fed chickens compared to fasted or refed chicks (P < 0.05). It was also greater in fed than refed chicks (P < 0.05) in abdominal adipose tissue [ 64 ]. In this experiment, the expression of AGPAT9 was significantly lower in the slow-growing group, which suggests that the fast-growing chickens might have a high fat content.…”