The effect of fasting and refeeding on mRNA expression of PepT1 and gastrointestinal hormones regulating digestion and food intake in zebrafish (Danio rerio)
- 1 December 2012
- journal article
- Published by Springer Science and Business Media LLC in Fish Physiology and Biochemistry
- Vol. 38 (6), 1565-1575
- https://doi.org/10.1007/s10695-012-9649-6
Abstract
In vertebrates, a significant part of ingested protein is absorbed as di- and tripeptides through a brush border membrane proton/oligopeptide transporter protein called PepT1. The aim of the present study was to determine the effect of short-term food deprivation and refeeding in adult zebrafish (Danio rerio) on gastrointestinal mRNA expression of PepT1 as well as on the satiety hormones cholecystokinin (CCK), gastrin-releasing peptide (GRP) and ghrelin (GHR) in order to elucidate a potential mechanism driving compensatory growth. Sixty adult zebrafish were stocked in a 40-L aquarium and fed daily a commercial flake diet to satiation for 10 days where the digestive tracts (DT) of sampled fish (n = 5) were dissected out. Samplings were repeated following 1, 2 and 5 days of food deprivation and after 1, 2 and 5 days of refeeding. The RNA was extracted from all sampled DTs and analyzed by quantitative real-time PCR for the mRNA expression of PepT1, rRNA 18S, CCK, GRP and GHR. PepT1 mRNA expression increased with successive refeedings reaching a level approximately 8 times higher than pre-fast levels. CCK, GRP and GHR mRNA levels also decreased during fasting, but increased only to pre-fasting levels with refeeding. Overall, the results suggest that PepT1 may be a contributing mechanism to compensatory growth that could influence CCK secretion and GRP and GHR activity.Keywords
This publication has 85 references indexed in Scilit:
- Protein hydrolysate-induced cholecystokinin secretion from enteroendocrine cells is indirectly mediated by the intestinal oligopeptide transporter PepT1American Journal of Physiology-Gastrointestinal and Liver Physiology, 2011
- Peptide transport and animal growth: the fish paradigmBiology Letters, 2011
- Transport of di- and tripeptides in teleost fish intestineAquaculture Research, 2010
- Impact of feed availability on PepT1 mRNA expression levels in sea bass (Dicentrarchus labrax)Aquaculture, 2009
- Compensatory Growth Induced in Zebrafish Larvae after Pre-Exposure to a Microcystis aeruginosa Natural Bloom Extract Containing MicrocystinsInternational Journal of Molecular Sciences, 2009
- Effect of starvation on transcriptomes of brain and liver in adult female zebrafish (Danio rerio)Physiological Genomics, 2008
- Compensatory growth in the Chinese longsnout catfish, Leiocassis longirostris following feed deprivation: Temporal patterns in growth, nutrient deposition, feed intake and body compositionAquaculture, 2005
- Caveolin-1-deficient mice show insulin resistance and defective insulin receptor protein expression in adipose tissueAmerican Journal of Physiology-Cell Physiology, 2003
- The lipostat, hyperphagia and catch-up growthAquaculture Research, 1999
- Effect of restricted feeding regimens on compensatory weight gain and body tissue changes in channel catfish Ictalurus punctatus in pondsAquaculture, 1995