Non-mammalian fat-1 gene prevents neoplasia when introduced to a mouse hepatocarcinogenesis model: Omega-3 fatty acids prevent liver neoplasia.

Abstract

We investigated the effect of a non-mammalian omega-3 desaturase in a mouse hepatocarcinogenesis model. Mice containing double mutations (DM) in c-myc and TGF-alpha (transforming growth factor-alpha), leading to liver neoplasia, were crossed with mice containing omega-3 desaturase. MRI analysis of triple mutant (TM) mice showed the absence of neoplasia at all time points for 92% of mice in the study. Pathological changes of TM (TGFalpha/c-myc/fat-1) mouse liver tissue was similar to control mouse liver tissue. Magnetic resonance spectroscopy (MRS) measurements of unsaturated fatty acids found a significant difference (p<0.005) between DM and TM transgenic (Tg) mice at 34 and 40 weeks of age. HPLC analysis of mouse liver tissue revealed markedly decreased levels of omega-6 fatty acids in TM mice when compared to DM (TGFalpha/c-myc) and control (CD1) mice. Mass spectrometry (MS) analysis indicated significantly decreased 16:0/20:4 and 18:1/20:4 and elevated 16:0/22:6 fatty acyl groups in both GPCho and GPEtn, and elevated 16:0/20:5, 18:0/18:2, 18:0/18:1 and 18:0/22:6 in GPCho, within TM mice compared to DM mice. Total fatty acid analysis indicated a significant decrease in 18:1n9 in TM mice compared to DM mice. Western blot analysis of liver tissue showed a significant (p<0.05) decrease in NF-kappaB (nuclear factor-kappaB) levels at 40 weeks of age in TM mice compared to DM mice. Microarray analysis of TM versus DM mice livers at 40 weeks revealed alterations in genes involved in cell cycle regulation, cell-to-cell signaling, p53 signaling, and arachidonic acid (20:4) metabolism. Endogenous omega-3 fatty acids were found to prevent HCC development in mice.

• Authors: J Griffitts, D Saunders, Y A Tesiram, G E Reid, A Salih, S Liu, T A Lydic, J V Busik, J X Kang, R A Towner
• Journal: Biochimica et biophysica acta (Biochim Biophys Acta) Vol. 1801 Issue 10 Pg. 1133-44 (Oct 2010) ISSN: 0006-3002 [Print] Netherlands
• PMID: 20620224 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: Copyright @ 2010 Elsevier B.V. All rights reserved.

Chemical References

• Caenorhabditis elegans Proteins
• Fatty Acids
• Fatty Acids, Omega-3
• fat-1 protein, C elegans
• Fatty Acid Desaturases

Topics

• Animals
• Caenorhabditis elegans (enzymology)
• Caenorhabditis elegans Proteins (metabolism)
• Carcinoma, Hepatocellular (drug therapy, genetics, pathology, prevention & control)
• Chromatography, High Pressure Liquid
• Disease Models, Animal
• Fatty Acid Desaturases (metabolism)
• Fatty Acids (chemistry, metabolism)
• Fatty Acids, Omega-3 (therapeutic use)
• Gene Expression Regulation, Neoplastic
• Gene Regulatory Networks
• Liver (pathology)
• Liver Neoplasms (drug therapy, genetics, pathology, prevention & control)
• Magnetic Resonance Imaging
• Magnetic Resonance Spectroscopy
• Mass Spectrometry
• Mice
• Oligonucleotide Array Sequence Analysis
• Tumor Burden