Long-term programming effect of early hypoxia and high carbohydrate diet at first-feeding on glucose metabolism in rainbow trout juveniles

Abstract

Environmental conditions experienced during early life play an important role in the long-term metabolic status of individuals. The present study investigated whether hypoxia exposure [for 24 h: 2.5 mg O l (20% dissolved O)] during the embryonic stage alone (hypoxic history) or combined with a 5-day high-carbohydrate (60%) diet stimulus at first feeding (HC dietary history) can affect glucose metabolism later in life, i.e. in juvenile fish. After 19 weeks of growth, we observed a decrease in final body mass in fish with an HC dietary history. Feed efficiency was significantly affected by both hypoxic and HC dietary histories. After a short challenge test (5 days) performed with a 30% carbohydrate diet in juvenile trout, our results also showed that, in trout that experienced hypoxic history, mRNA levels of gluconeogenic genes in liver and glucose transport genes in both liver and muscle were significantly increased at the juvenile stage. Besides, mRNA levels of glycolytic genes were decreased in fish with an HC dietary history. Both hypoxic and dietary histories barely affected plasma metabolites or global epigenetic modifications in juvenile fish after the challenge test. In conclusion, our results demonstrated that an acute hypoxic stimulus during early development alone or combined with a hyperglucidic stimulus at first feeding can modify growth performance and glucose metabolism at the molecular level in juvenile trout.

Early feeding of rainbow trout (Oncorhynchus mykiss) with methionine deficient diet over a two-week period: consequences for liver mitochondria in juveniles

“…For cleaved PARP, the amino sequence of the corresponding protein was monitored in the SIGENAE database (http://www.sigenae.org) to check for the conservation of the antigen sequence with the corresponding sequence from mammals, ensuring a good specificity of the mammalian antibody used in the analysis of our samples. In order to measure the global levels of selected histone modification (H3K4me3, H3K9me3 and H3K36me3), histones from livers were extracted according to a previously detailed protocol (Liu et al, 2017). Histone isolation was used for western blot analysis as described above and using the appropriate antibodies: anti-H3K4me3 (C15410003, Diagenode); anti-H3K9me3 (C15410056, Diagenode); anti-H3K36me3 (15410192, Diagenode); and anti-H3 (ab1791, Abcam).…”

“…Determination of mitochondrial DNA (mtDNA) copy number DNA isolation was performed on fish liver sampled 16 h after the last meal (second sampling, N=6 per condition) following a previously detailed protocol (Liu et al, 2017). mtDNA copy number was measured using qPCR as described above.…”

Phenotypic plasticity and epigenetics of fish: embryo temperature affects later-developing life-history traits

“…Other stressors that affect embryos include hypoxia and chemical contamination (cf. Ho & Berggren 2012, Dubinska-Magiera et al 2016, Wang et al 2016, Liu et al 2017. Temperature also has pervasive, controlling effects on the ecology and physiology of poikilotherms later in life (e.g.…”

DNA methylation of the promoter region of bnip3 and bnip3l genes induced by metabolic programming

“…For instance, an acute hypoxic stimulus applied in rainbow trout at embryo stage modified mRNA levels of several glucose-metabolism related genes at first feeding [ 14 ]. Moreover, after the embryonic hypoxic stimulus, the glucose metabolism in liver and muscle of rainbow trout juvenile was impacted, confirming a long term programming effect of a very early stimulus [ 15 ]. Programming can also be driven through parental nutrition.…”