One of the several ways that growth hormone (GH) relates to the growth physiology of teleost fishes, like tilapia, is that it helps them absorb nutrients. In a new study from the Dept. of Human Nutrition, Food and Animal Sciences, alumnus Cody Petro-Sakuma, Fritzie Celino-Brady, and mentor Andre Seale investigated the effects of GH on the gene expression of nutrient transporters in the Mozambique tilapia (Oreochromis mossambicus). The paper appeared in the journal General and Comparative Endocrinology.
The researchers took out the tilapia’s pituitary gland and gave it hormone replacement. Their goal was to assess whether GH directs the gene expression of different receptors, such as the GH receptor, peptide transporters, the amino acid transporter, the glucose transporter, and more. They also checked where in the intestine this gene expression showed up.
The modified tilapia showed diminished expression of some of these genes, and not all of the receptor levels were restored when the fishes received GH replacement. The authors’ findings indicate that “GH supports growth, at least in part, by stimulating the gene expression of its cognate receptor and key nutrient transporters in the intestine.”
As Andre explains, “Using the tilapia as a model species, the paper shows that the growth-promoting effects of growth hormone occur via the stimulation of specific nutrient transporters in the intestine.”
Read the full paper here.