Cysteamine improves growth and the GH/IGF axis in gilthead sea bream (Sparus aurata): in vivo and in vitro approaches

Front Endocrinol (Lausanne). 2023 Jul 20:14:1211470. doi: 10.3389/fendo.2023.1211470. eCollection 2023.

Abstract

Aquaculture is the fastest-growing food production sector and nowadays provides more food than extractive fishing. Studies focused on the understanding of how teleost growth is regulated are essential to improve fish production. Cysteamine (CSH) is a novel feed additive that can improve growth through the modulation of the GH/IGF axis; however, the underlying mechanisms and the interaction between tissues are not well understood. This study aimed to investigate the effects of CSH inclusion in diets at 1.65 g/kg of feed for 9 weeks and 1.65 g/kg or 3.3 g/kg for 9 weeks more, on growth performance and the GH/IGF-1 axis in plasma, liver, stomach, and white muscle in gilthead sea bream (Sparus aurata) fingerlings (1.8 ± 0.03 g) and juveniles (14.46 ± 0.68 g). Additionally, the effects of CSH stimulation in primary cultured muscle cells for 4 days on cell viability and GH/IGF axis relative gene expression were evaluated. Results showed that CSH-1.65 improved growth performance by 16% and 26.7% after 9 and 18 weeks, respectively, while CSH-3.3 improved 32.3% after 18 weeks compared to control diet (0 g/kg). However, no significant differences were found between both experimental doses. CSH reduced the plasma levels of GH after 18 weeks and increased the IGF-1 ones after 9 and 18 weeks. Gene expression analysis revealed a significant upregulation of the ghr-1, different igf-1 splice variants, igf-2 and the downregulation of the igf-1ra and b, depending on the tissue and dose. Myocytes stimulated with 200 µM of CSH showed higher cell viability and mRNA levels of ghr1, igf-1b, igf-2 and igf-1rb compared to control (0 µM) in a similar way to white muscle. Overall, CSH improves growth and modulates the GH/IGF-1 axis in vivo and in vitro toward an anabolic status through different synergic ways, revealing CSH as a feasible candidate to be included in fish feed.

Keywords: GH; IGF; aquaculture; cysteamine; feed additive; gilthead sea bream; myocyte; somatotropic axis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animal Feed
  • Animals
  • Cysteamine* / pharmacology
  • Growth Hormone / metabolism
  • Insulin-Like Growth Factor I* / metabolism
  • Insulin-Like Growth Factor II / metabolism
  • Sea Bream* / growth & development
  • Sea Bream* / metabolism

Substances

  • Cysteamine
  • Growth Hormone
  • Insulin-Like Growth Factor I
  • Insulin-Like Growth Factor II

Grants and funding

This publication is part of the R+D+i projects AGL2015-70679-R and RTI2018-100757-B-I00 to JG and JB, and AGL2017-89436-R funded by the Spanish “Ministerio de Ciencia e Innovación” (MCIN/AEI/10.13039/501100011033/), the “Xarxa de Refèrencia d’R+D+I en Aqüicultura” (Aqüival Cist-Crec) and the 2017-SGR1574 from the “Generalitat de Catalunya”. SB-P, EV and MP-A, were funded by predoctoral fellowships from the MINECO grants PRE2018-085580, BES-2013-062949 and BES-2016-078697, respectively.