Effects of Kupffer cells stimulated by triglyceride and very low-density lipoprotein on proliferation of rat hepatic stellate cells

Objective To study the effects of triglyceride, very low-density lipoprotei n (VLDL), and Kupffer cell-conditioned medium (KCCM) derived from triglycer ide and VLDL treatment on proliferation of rat hepatic stellate cells (HSC) . Methods HSC and Kupffer cells were isolated and cultured from liver of Wist ar rats by in situ perfusion with proteinase and collagenase, and density g radient centrifugation with Nycodenz; HSC and Kupffer cells were identified by immunohistochemistry, endocytosis, and ultrastructure, etc. Kupffer cel ls were incubated with triglyceride (25 mu g/ml) and VLDL (25 mu g/ml) for 24 hours, KCCM were prepared, and MTT colorimetric assay was detected for H SC proliferation. Results HSC proliferation was 0.1894 +/- 0.0316 (12.5 mu g/ml), 0.1637 +/- 0.0243 (25 mu g/ml), 0.1450 +/- 0.0264 (50 mu g/ml), 0.1212 +/- 0.0275 (100 mu g/ml), 0.1226 +/- 0.0138 (200 mu g/ml) and 0.0990 +/- 0.0163 (400 mu g/ ml) in the presence of triglyceride and was 0.1583 +/- 0.0314 (6.25 mu g/ml ), 0.1642 +/- 0.0269 (12.5 mu g/ml), 0.1834 +/- 0.0498 (25 mu g/ml), 0.1964 +/- 0.0287 (50 mu g/ml) and 0.2202 +/- 0.0284 (100 mu g/ml) in presence of VLDL, respectively. Compared with the control, HSC proliferation at 400 mu g/ml of triglyceride was lower (P < 0.01), but at 12.5 mu g/ml of triglyce ride and 25, 50, 100 mu g/ml of VLDL higher (P < 0.05 or 0.01); HSC prolife ration was 0.1569 +/- 0.0144, 0.1924 +/- 0.0113 and 0.1871 +/- 0.0116 in th e presence of KCCM, KCCM + triglyceride and KCCM + VLDL, respectively. Comp ared with the control and KCCM, KCCM + triglyceride and KCCM + VLDL might p romote HSC proliferation (P < 0.01); there was no statistical significance between KCCM + triglyceride and KCCM + VLDL (P > 0.05); KCCM was greater in HSC proliferation than the control, but there was no significant change (P > 0.05). Conclusions Triglyceride, VLDL, and KCCM stimulated by triglyceride and VLD L might promote HSC proliferation and be associated with fatty liver and he patic fibrogenesis.