Toxicological Research

Korean Society of Toxicology & Korea Environmental Mutagen Society (한국독성학회)
권호 표지

Disruption of Sphingolipid Metabolism as a Potential Mechanism of Fumonisin Inhibition of Cell Growth in $LLC-PK_1$ Cells

  • Yoo, Hwan-Soo (Pulmonary-Critical Care Medicine Branch, NHLBI, National Institutes of Health) ;
  • Yun, Yeo-Pyo (College of Pharmacy, Chungbuk National University)
  • Published : 1995.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

Fumonisins are a family of mycotoxins produced by the fungus Fusarium moniliforme which is a common contaminant in corn. Fumonisins are potent inhibitors of sphingosine and sphinganine N-acyltransferase (ceramide synthase), key enzymes in sphingolipid metabolism. The purpose of this study was to provide the evidence that the elevated levels of free sphingoid bases (primarily sphinganine) and depletion of complex sphingolipids were closely related to the inhibition of cell growth in LLC-$PK_1$ cells exposed to fumonisin $B_1$$(\leq 35 {\mu}M)$. Concentrations of fumonisin $B_1$ between 10 and $35 {\mu}M$ were known to inhibit cell growth without cytotoxicity in $LLC-PK_1$ cells (Yoo et al. Toxicol. Appl. Pharmacol. 114, 9-15, 1992). Cells exposed to 35$\mu M$ fumonisin B$_1$ for 48 and 72 hr developed a fibroblast-like (elongated and spindle-shaped) appearance and were less confluent than normal cells. At between 24 and 48 hr after exposure to fumonisin $B_1$ cells were beginning to show the inhibition of cell growth and at 72 hr the number of viable cells in fumonisin-treated cultures was about 50% of concurrent control cultures. During the 24 hr lag period preceding inhibition of cell growth, the free sphinganine levels in cells exposed to $35 {\mu}M$ fumonisin $B_1$ were highly elevated (approximately 230 fold higher than normal cells). The elevated levels of free sphinganine were $435\pm14$$pmoles/{10^6}$ cells at 48 hr and approximately TEX>$333\pm11$$pmoles/{10^6}$ cells in cells exposed to $35{\mu}M$ fumonisin$B_1$ at 72 hr, while the levels of free sphinganine in normal cells were less than 2$pmoles/{10^6}$ cells. Under the same condition, depletion of intracellular complex sphingolipids as a consequence of fumonisin inhibition of de novo sphingolipid biosynthesis and turnover pathway was appeared. Content of free sphingold bases in dividing cells was more elevated than in confluent cells at 24-48 hr after cells were exposed to $20{\mu}M$ fumonisin $B_1$. The dividing cells were showing the inhibition of cell growth at 48-72 hr and $20{\mu}M$ fumonisin $B_1$. The results of this study support the hypothesis that the inhibition of cell growth is very well related to the disruption of sphingolipid metabolism in $LLC-PK_1$ cells.

Keywords

References

  1. Atherosclerosis v.94 Atherogenic effects in non-human primate of Fusarium moniliforme cultures added to a carbohydrate diet Fincham,J.E.;Marasas,W.F.O.;Taijaard,J.J.F.;Kriek,N.P.J.;Badenhorst,C.J.;Gelderblom,W.C.A.;Seier,J.V.;Smuts,C.M.;Faber,M.;Weight,M.J.;Slazus,W.;Woodrof,C.W.;van Wyk,M.J.;Kruger,M.;Thiel,P.G.
  2. J. Biol. Chem. v.267 Sphingolipids are essential for the growth of chinese hamster ovary cells. Restoration of the growth of a mutnat defective in sphingolipid base biosynthests with exogenous sphingolipids Hanada,K.;Nishijima,M.;Kiso,M.;Hasegawa,A.;Fujita,S.;ogawa,T.;Akamatsu,Y.
  3. J. Biol. Chem. v.261 Sphingosine inhibition of protein kinase C activity and of phorbol dibutyrate binding in vitro and in human platelets Hannun,Y.A.;Loomis,C.R.;Merrill,A.H.;Bell,R.M.
  4. J. Biol. Chem. v.268 Inhibition of sphingolipid synthesis affects axonal outgrowth in cultured hippocampal neurons Harel,R.;Futerman,A.H.
  5. Biochim. Biophys. Acta v.1044 An update of the enzymology and regulation of sphingolmyelin metabolism Merrill,A.H.,Jr.;Jones,D.D.
  6. J. Bioenerg, Biomemb. v.23 Cell regulation by sphingosine and more complex sphingolipids Marrill,A.H.,Jr.
  7. Advances in Molecular Biology and cell Bilolgy Sphingolipids as regulators of cellular growth, differentiation, and behavior Merrill,A.H.,Jr.;Liotta,D.C.;Riley,R.T.;R.W.Gross(ed.)
  8. J. Biol. chem. v.261 inhibition of phorbol ester-dependent differentiation of human promyelocytic leukemic (HL-60) cell sphinganine and other long-chain bases Merrill,A.H.,Jr.;Sereni,A.M.;Stevens,V.L.;Hannun,Y.A.;Bell,R.M.;Kinkade,J.M.,Jr.
  9. J. Biol. chem. v.268 Fumonisin B₁inhibits shingosine (sphinganine) N-acyltransferase and de novo sphingolipid biosynthesis in cultured neurons in situ Merrill,A.H.,Jr.;van Echten,G.;Wang,E.;Sandhoff,K.
  10. Anal. Biochem. v.171 Quantitation of free sphingosine in liver by high performance liquid chromatography Merrill,A.H.,Jr.;Wang,E.;Mullins,R.E.;Jamison,W.C.;Nimkar,S.;Liotta,D.C.
  11. Annu. Rev phytopathol. v.31 Fumonisins, mycotoxins produced by Fusarium species: biology, chemistry, and significance Nelson,P.E.;Desjardins,A.E.;Plattner,R.D.
  12. Tetrahedron Lett. v.29 A stereoselective synthesis of sphingosine, a protein kinase C inhibitor Nimkar,S.;Menaldino,D.;Merrill,A.H.,Jr.;Liotta,D.
  13. J. Biol. Chem. v.265 Inhibition of Na, K-ATPase and sodium pump by protein kinase C regulators sphingosine, lysophosphatidylcholine, and oleic acid Oishi,K.;Zheng,B.;Kuo,J.F.
  14. Mycologia v.82 A method of detection of fumonisins in corn samples associated with field cases of equine leukoencephalomalacia Plattner,R.D.;Norred,W.P.;Bacon,C.W.;Voss,K.A.;Peterson,R.;Shakelford,D.D.;Weisleder,D.A.
  15. Toxicol. Appl. Pharmacol. v.118 Alteration of tissue and serum sphinganine to sphingosine ratio: an early biomarker in pigs of exposure to fumonisin-containing feeds Riley,R.T.;An,N.H.;Showker,J.L.;Yoo,H.S.;Norred,W.P.;chamberlain,W.J.;Wang,E.;Merrill,A.H.,Jr.;Motelin,G.;Beasley,V.R.;Haschek,W.M.
  16. J. Biochem. Toxicol. v.2 Age and growth related changes in cyclopiazoic acid-potentiated lipophilic cation accumulation by cultured cells and binding to freezethaw lysed cells Riley,R.T.;Goeger,D.E.;Showker,J.L.;Cole,R.J.;Dorner,J.
  17. J. Nutr. v.124 Dietary fumonisin B₁induces disruption of sphingolipid metabolism in Sprague-Dawley rats: A new mechanism of nephrotoxicity Riley,R.T.;Hinton,D.M.;Chamberlain,W.J.;Bacon,C.W.;Wang,E.;Merrill,A.H.,Jr.;Voss,K.A.
  18. SAS/STAT Guide for personal computers SAS Institute, Inc.
  19. Mycopathologia v.116 Toxicity of mycotoxins fumonisins B₁and B₂and Alternaria alternata f. sp. lycopersica toxin (AAL) in cultured mammalian cells Shier,W.T.;Abbas,H.K.;Mirocha,C.J.
  20. Adv. Lipid Res. v.25 The role of sphingosine in cell growth regulation and transmembrane signaling Spiegel,S.;Olivera,A.;Carlson,R.D.
  21. J. Biol. Chem. v.266 Inhibition of sphingolipid biosynthesis by fumonisins: implications for diseases associated with Fusartum moniliforme Wang,E.;Norred,W.P.;Bacon,C.W.;Riley,R.T.;Merrill,A.H.,Jr.
  22. J. Nutr. v.122 Alteration of serum sphingolipid upon exposure of ponies to feed containing fumonisins, mycotoxins produced by Fusarium moniliforme Wang,E.;Ross,P.F.;Wilson,T.M.;Riley,R.T.
  23. J. Biol. Chem. v.261 Inhibition of the oxidative burst in human neutrophils by sphingoid long-chain bases Wilson,E.;Olcott,M.C.;Bell,R.M.;Merrill,A,H.,Jr.;Lambeth,J.D.
  24. J. Vet. Diag. Invest. v.2 Fumonisin B₁levels associated with an epizootic of equine leukoencephalomalacia Wilson,T.M.;Ross,P.F.;Rice,L.G.;Osweiler,G.D.;Nelson,H.A.;Owens,D.L.Plattner,R.D.;Reggiardo,C.;Noon,T.H.;Pickrell,J.W.
  25. Toxicol. Appl. Pharmacol. v.114 Fumonisin inhibition of de novo sphingolipid biosynthesis and cytotoxicity are correlated in LLC-PK₁cells Yoo,H.S.;Norred,W.P.;Wang,E.;Merrill,A.H.,Jr.;Riley,R.T.