Effects of lipopolysaccharides stimulated Kupffer cells on activation of rat hepatic stellate cells.

AIM: To study the effects of Kupffer cell-conditioned medium (KCCM) derived from lipopolysaccharide (LPS) treatment on proliferation of rat hepatic stellate cells (HSC). METHODS: HSC and Kupffer cells were isolated from the liver of Wistar rats by in situ perfusion with pronase and collagenase and density gradient centrifugation with Nycodenz and cultured. KCCM was prepared and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay was used to detect HSC proliferation. The content of type IV collagen and laminin secreted by HSC in the HSC-conditioned medium was determined by radioimmunoassay. TGF-beta(1) production in the KCCM was detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: HSC and Kupffer cells isolated had high purity. One microgram per mililiter LPS-activated KCCM and unstimulated KCCM could significantly promote HSC proliferation [0.132+/-0.005 and 0.123+/-0.008 vs control group (0.100+/-0.003), P<0.01], and there was a difference between them (P<0.05). Ten microgram per mililiter LPS-activated KCCM (0.106+/-0.010) was unable to promote HSC proliferation (P>0.05). Adding anti-TGF-beta(1) antibodies could suppress the proliferation promoted by unstimulated KCCM and LPS (1 microg/ml)-activated KCCM (0.109+/-0.009 vs 0.123+/-0.008, 0.115+/-0.008 vs 0.132+/-0.005, P<0.01). LPS (1 microg/ml or 10 microg/ml) could not promote HSC proliferation immediately (0.096+/-0.003 and 0.101+/-0.004 vs 0.100+/-0.003, P>0.05). There was a parallel behavior between HSC proliferation and increased ECM level. One microgram per mililiter LPS-activated KCCM contained a larger amount of TGF-beta(1) than unstimulated KCCM. CONCLUSION: The technique for isolation of HSC and Kupffer cells described here is simple and reliable. KCCM stimulated by LPS may promote HSC proliferation and collagen accumulation, which are associated with hepatic fibrogenesis.

[Studies on the preparation of camptothecin niosomes].

AIM: To study the non-ion surfactant vehicle (niosome) entrapped-camptothecin. METHODS: The niosome loaded with camptothecin was prepared from Span and cholesterol using aqueous dispersion of film. The vehicles were visualised by transmission electron microscopy and sized by laser particle analyzer on a Malvern Mastersizer. An HPLC analysis method of the camptothecin was established by fluorescence detection. The entrapment efficiency of the niosomes containing camptothecin was determinated after the ultracentrifugation of the niosome. The antitumor activities of the vehicles on S180 sarcoma in mouse were studied. RESULTS: The given niosomes were the suspension finely dispersed in aqueous solution. They were spherical vehicles with the single lamellar bilayers similar to phospholipid vehicles. The mean sizes of the vehicles were (565 +/- 6) nm. The recovery of the HPLC analysis method was 100.3% with 0.4% RSD. The entrapment efficiency of the camptothecin encapsulated by the niosome was 61%. The inhibition (%) of the niosome loaded with camptothecin on S180 sarcoma in mouse were 76.1% (P < 0.05). After the given dose the weight of the mouse of the niosome groups were 92.7% (P > 0.05) and 134.7% of blank control groups and compatothecin solution groups, respectively. CONCLUSION: The camptothecin niosomes were spherical in shape and similar to phospholipid vehicles with singlelamellar bilayers. Their size distributions were narrow. Their entrapment efficiency were higher. Its antitumor activity was better than camptothecin.