Lipids

, 46:495

Growth Hormone Enhances Arachidonic Acid Metabolites in a Growth Hormone Transgenic Mouse

Original Article

DOI: 10.1007/s11745-011-3548-y

Cite this article as:
Oberbauer, A.M., German, J.B. & Murray, J.D. Lipids (2011) 46: 495. doi:10.1007/s11745-011-3548-y

Abstract

In a transgenic growth hormone (GH) mouse model, highly elevated GH increases overall growth and decreases adipose depots while low or moderate circulating GH enhances adipose deposition with differential effects on body growth. Using this model, the effects of low, moderate, and high chronic GH on fatty acid composition were determined for adipose and hepatic tissue and the metabolites of 20:4n-6 (arachidonic acid) were characterized to identify metabolic targets of action of elevated GH. The products of Δ-9 desaturase in hepatic, but not adipose, tissue were reduced in response to elevated GH. Proportional to the level of circulating GH, the products of Δ-5 and Δ-6 were increased in both adipose and hepatic tissue for the omega-6 lipids (e.g., 20:4n-6), while only the hepatic tissues showed an increase for omega-3 lipids (e.g., 22:6n-3). The eicosanoids, PGE2 and 12-HETE, were elevated with high GH but circulating thromboxane was not. Hepatic PTGS1 and 2 (COX1 and COX 2), SOD1, and FADS2 (Δ-6 desaturase) mRNAs were increased with elevated GH while FAS mRNA was reduced; SCD1 (stearoyl-coenzyme A desaturase) and SCD2 mRNA did not significantly differ. The present study showed that GH influences the net flux through various aspects of lipid metabolism and especially the desaturase metabolic processes. The combination of altered metabolism and tissue specificity suggest that the regulation of membrane composition and its effects on signaling pathways, including the production and actions of eicosanoids, can be mediated by the GH regulatory axis.

Keywords

Growth hormone Arachidonic acid Fatty acid composition 

Abbreviations

ARA

Arachidonic acid

cDNA

Complementary DNA

COX

Cyclooxygenase

DHA

Docosahexaenoic acid

ELISA

Enzyme-linked immunosorbent assay

FADS

Fatty acid desaturase

FAS

Fatty acid synthetase

GAPDH

Glyceraldehyde-3-phosphate dehydrogenase

GH

Growth hormone

HETE

Hydroxyeicosatetraenoic

HPLC

High-performance liquid chromatography

MMLV-RT

Moloney murine leukemia virus-reverse transcriptase

mRNA

Messenger ribonucleic acid

oMt1a-oGH

Ovine metallothionein 1a promoter driving ovine GH transgene construct

PCR

Polymerase chain reaction

PGE2

Prostaglandin E

PTGS

Prostaglandin H synthase

qPCR

Quantitative real time polymerase chain reaction

SCD

Stearoyl-coenzyme A desaturase

SOD

Superoxide dismutase

SREBP

Sterol regulatory element binding protein

STAT

Signal transducers and activators of transcription

ZnSO4

Zinc sulfate

Copyright information

© AOCS 2011

Authors and Affiliations

  • A. M. Oberbauer
    • 1
  • J. B. German
    • 2
  • J. D. Murray
    • 1
    • 3
  1. 1.Department of Animal ScienceUniversity of CaliforniaDavisUSA
  2. 2.Food Science and TechnologyUniversity of CaliforniaDavisUSA
  3. 3.Veterinary Health, Reproduction, and Population BiologyUniversity of CaliforniaDavisUSA

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