Lipidome of Activated Hepatic Stellate Cells Figure 6. PUFA-containing TAG species, but not phospholipid species, are induced during HSC activation. A. Contour plots of HPLC- APCI-MS analysis of HSC at day 0 and 7, showing an increase in long chain fatty acid-containing TAG species at day 7. From every ion in the m/z 880– 1050 region its relative abundance (amount of blackness) and retention time in the HPLC separation is shown. TAG species with the same total number of carbon atoms in the three acyl chains (denoted on the right hand side), but different number of double bonds (:n) form diagonal ‘‘stripes’’ at specific m/z regions. B. Quantification of the total amount of TAG-PUFA (m/z 900–1050) and PC-PUFA species in HSCs at day 0, 4 and 7. Values are expressed relative to the level of lipid present at day 0. The results represent the means 6 SEM of three experiments. C. TAG species containing one, two or three 22:5 acyl moieties are induced during HSC activation. The results represent the means 6 SEM of three experiments. doi:10.1371/journal.pone.0034945.g006 increase or translocation of CCTa in activated rat HSCs, suggesting that the existing CCTa levels suffice for the generation of enough PC for the phospholipid monolayers covering the novel LDs and for the newly formed cell extensions. The translocation of the LDs towards the cell extensions probably involves directed movement along microtubules as it was inhibited by nocadozole. The signals and mechanism of LD movements are largely PLoS ONE | www.plosone.org 7 April 2012 | Volume 7 | Issue 4 | e34945