[Effect of collagens and growth factors (TGFß1, PDGF-BB) on cytoskeletal reorganization and cell migration in hepatic stellate cells]

Abstract

Objective: To evaluate the effects of collagens and growth factors TGFß1 and PDGF-BB on the cytoskeletal components and migration in cultured rat hepatic stellate cells (HSCs).

Methods: Primary rat hepatic stellate cells were isolated and cultured. A Transwell Chamber system was used to observe the changes of serum starved HSCs haptotactic migration (direct stimulation) and chemotactic migration (indirect stimulation) after collagens and growth factors treatment. Changes in actin cytoskeletal organization were visualized by fluorescence staining using FITC-labeled phalloidin and the fluorescence images were recorded using confocal microscopy.

Results: TGFß1 enhanced significantly the motility of primary HSCs at 5 ng/ml: for haptotactic migration cells: 131.37+/-3.15 vs 102.93+/-1.01, F=40.84, P<0.05; for chemotactic migration cells: 210.17+/-1.78 vs 102.93+/-1.01, F=64.53, P<0.05. PDGF-BB enhanced significantly the motility of primary HSCs at 10 ng/ml (haptotactic migration cells: 203.67+/-7.54 vs 102.93+/-1.01, F=40.90, P<0.05; chemotactic migration cells: 319.56+/-11.71 vs 102.93+/-1.01, F=54.57, P<0.05); Both chemotactic and haptotactic stimuli with 100 microg/ml collagen type I significantly increased HSCs migration: for haptotactic migration cells: 127.20+/-6.47 VS 102.93+/-1.01, F=41.01, P is less than 0.05; for chemotactic migration cells: 201.52+/-11.28 vs 102.93+/-1.01, F=36.49, P<0.05; however, collagen type IV had no effect on HSCs migration. Serum-starved, untreated cells had a rounded-up morphology. PDGF-BB and TGFß1 induced a rapid morphological change concomitant with a robust reorganization of actin cytoskeleton in HSCs.

Conclusions: Collagen type I, PDGF-BB and TGFß1 could induce cell migration in HSCs, but collagen type IV has no such effect. PDGF-BB and TGFß1 could induce the actin cytoskeleton reorganization in HSCs.