Triglyceride accumulation and altered composition of triglyceride-associated fatty acids in the skin of tenascin-X-deficient mice.
Tenascin-X (TNX) is a member of the tenascin family of glycoproteins of the extracellular matrix. Here, we observed abnormalities in the skin of TNX-deficient mice in comparison with that of wild-type mice. Histological analysis with Oil Red O staining demonstrated that there was considerable accumulation of lipid in the skin of TNX-deficient (TNX-/-) mice. By thin-layer chromatography of total lipids, it was found that the level of triglyceride was significantly increased in TNX-/- mice. The mRNA levels of most of the lipogenic enzyme genes examined were remarkably increased in TNX-/- mice. By gas chromatography-mass spectrometry analysis of triglyceride-associated fatty acids in the skin, saturated fatty acid palmitoic acid was decreased, whereas unsaturated fatty acids palmitoleic acid and oleic acid were increased in TNX-/- mice compared with those in wild-type mice. Conversely, fibroblast cell lines transfected with TNX showed a significant decrease in the amount of triglyceride. An increase in the saturated fatty acid stearic acid and decreases in the unsaturated fatty acids palmitoleic acid, oleic acid and linoleic acid, compared to those in mock-transfected cells were also caused by over-expression of TNX. These results indicate that TNX is involved in the regulation of triglyceride synthesis and the regulation of composition of triglyceride-associated fatty acids.
Matsumoto
Ken-ichi
K
Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita 12, Nishi 6, Kita-ku, Sapporo 060-0812, Japan. kematsum@pharm.hokudai.ac.jp
Sato
Takashige
T
Oka
Seiko
S
Orba
Yasuko
Y
Sawa
Hirofumi
H
Kabayama
Kazuya
K
Inokuchi
Jin-ichi
J
Ariga
Hiroyoshi
H
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D004798:Enzymes / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis*; D050356:Lipid Metabolism; D051379:Mice; D018345:Mice, Knockout; D012867:Skin / Q000033:anatomy & histology / Q000737:chemistry* / Q000378:metabolism; D040521:Subcutaneous Tissue / Q000378:metabolism; D019063:Tenascin / Q000235:genetics / Q000502:physiology*; D014280:Triglycerides / Q000096:biosynthesis* / Q000737:chemistry* / Q000378:metabolism
D004798:Enzymes; D005227:Fatty Acids; D019063:Tenascin; D014280:Triglycerides; C081865:tenascin X