Effect of Cold Stress on Expression of AMPKα–PPARα Pathway and Inflammation Genes

Abstract

Animals are exposed to various environmental stresses every day, including the stress associated with living in cold temperatures. The aim of this study was to investigate the possible mechanisms of interaction between lipid metabolism and inflammation induced by cold stress in the livers of chickens. Fifteen-day-old male chicks were randomly allocated into 12 groups (10 chickens per group). After exposure of the chickens to the cold stress, cholesterol fractionation was used to examine high-density lipoprotein (HDL) and low-density lipoprotein (LDL) concentrations. Aminotransferase activities were examined with the use of the aspartate transaminase (AST) and alanine transaminase (ALT) assay. The AMP-activated protein kinase alpha-proliferator-activated receptor alpha (AMPKalpha-PPARalpha) pathway genes (AMPKalpha1, AMPKalpha2, PPARalpha, carnitine palmitoyltransferaseI [CPTI], acetyl-CoA carboxylase [ACC]) and inflammatory cytokines (prostaglandin E synthase [PGEs], inducible nitric oxide synthase [iNOS], heme oxygenase-1 [HO-1], nuclear factor kappa-light-chain-enhancer of activated B cells [NF-kappaB], cyclooxygenase-2 [COX-2], and TNF-alpha-like factor [LITAF]) were also measured. The results showed that during the response to cold stress, serum LDL and HDL cholesterol concentrations increased. Histopathologic analyses provided evidence that liver tissues were seriously injured in the chickens exposed to the cold stress. Serum aminotransferase activities were also increased in the group of animals exposed to the cold stress. Additionally, the expressions of AMPKalpha-PPARalpha pathway genes and inflammatory cytokine genes were significantly increased in the animals exposed to cold temperatures. These results suggested that increased inflammation was a feature associated with a lipid-metabolism disorder in the livers of chickens exposed to cold stress.

Chronic Mild Cold Conditioning Modulates the Expression of Hypothalamic Neuropeptide and Intermediary Metabolic-Related Genes and Improves Growth Performances in Young Chicks

“…Consistent with our hypothesis and in agreement with previous studies [ 57 ], CMCC down regulated the hepatic expression of the key lipogenic genes FAS (which catalyzes the synthesis of long-chain fatty acid synthesis through the condensation of acetyl-CoA and malonyl-CoA in a complex seven-step reaction), ACCα (multifunctional enzyme which catalyzes the carboxylation of acetyl-CoA to malonyl-CoA, the rate-limiting step in fatty acid synthesis) and ME (which catalyzes the oxidative decarboxylation of malate to pyruvate and generates NADPH for fatty acid biosynthesis). The concomitant decrease in hepatic SREBP1/2 mRNA abundance indicates that CMCC down regulated the lipogenic gene expression at transcriptional levels through these key transcriptional factors [ 58 ].…”

Effect of low incubation temperature and low ambient temperature until 21 days of age on performance and body temperature in fast-growing chickens

“…However, the constantly cool condition T 2 applied post hach negatively affected the health of the chicks, probably promoting the survival of the fittest, in accordance with Zhang et al. ( 2014 ), pointing out the increased inflammation associated with lipid-metabolism disorders in the livers of chickens exposed to cold stress. Previous data showed that at hatching, chicks have very low storage of minerals (Yair et al., 2015 ).…”

Dietary supplementary glutamine and L-carnitine enhanced the anti-cold stress of Arbor Acres broilers

“…Cold stress also significantly increases systemic energy expenditure and causes substantial metabolic changes, including decreased insulinemia, increased hepatic glucose production, feed intake changes, and increased glucose and fat utilization in peripheral tissues (Yao et al, 2018;Liu et al, 2019;Shi et al, 2019). Meanwhile, cold stress affects the production performance and product quality of livestock and poultry (Zhang et al, 2014;Hao et al, 2015;Nguyen et al, 2015). For example, cold stress not only stunts the growth and development of broilers, but also requires more feed to maintain their body temperature, resulting in low feed conversion rate and waste of resources, as well as poor weight uniformity and carcass quality of broilers.…”