RESUMO
BACKGROUND: Pancreatic stellate cells (PSCs) play a critical role in the development of pancreatic fibrosis. In this study we used a novel method to isolate and culture rat PSCs and then investigated the inhibitory effects of adipose-derived stem cells (ADSCs) on activation and proliferation of PSCs. METHODS: Pancreatic tissue was obtained from Sprague-Dawley rats for PSCs isolation. Transwell cell cultures were adopted for co-culture of ADSCs and PSCs. PSCs proliferation and apoptosis were determined using CCK-8 and flow cytometry, respectively. alpha-SMA expressions were analyzed using Western blotting. The levels of cytokines [nerve growth factor (NGF), interleukin-10 (IL-10) and transforming growth factor-beta1 (TGF-beta1)] in conditioned medium were detected by ELISA. Gene expression (MMP-2, MMP-9 and TIMP-1) was analyzed using qRT-PCR. RESULTS: This method produced 17.6+/-6.5X10(3) cells per gram of the body weight with a purity of 90%-95% and a viability of 92%-97%. Co-culture of PSCs with ADSCs significantly inhibited PSCs proliferation and induced PSCs apoptosis. Moreover, alpha-SMA expression was significantly reduced in PSCs+ADSCs compared with that in PSC-only cultures, while expression of fibrinolytic proteins (e.g., MMP-2 and MMP-9) was up-regulated and anti-fibrinolytic protein (TIMP-1) was down-regulated. In addition, NGF expression was up-regulated, but IL-10 and TGF-beta1 expressions were down-regulated in the co-culture conditioned medium compared with those in the PSC-only culture medium. CONCLUSIONS: This study provided an easy and reliable technique to isolate PSCs. The data demonstrated the inhibitory effects of ADSCs on the activation and proliferation of PSCs in vitro.
Assuntos
Tecido Adiposo/citologia , Apoptose , Proliferação de Células , Células Estreladas do Pâncreas/fisiologia , Células-Tronco , Actinas/metabolismo , Animais , Técnicas de Cocultura , Meios de Cultivo Condicionados , Regulação para Baixo/genética , Expressão Gênica , Interleucina-10/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Fator de Crescimento Neural/metabolismo , Ratos , Ratos Sprague-Dawley , Inibidor Tecidual de Metaloproteinase-1/genética , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima/genéticaRESUMO
Hepatic stellate cells (HSCs) play an important role in the process of liver fibrosis. In this study, we investigated the inhibitory effects of capsaicin on HSCs and liver fibrosis. Cultured HSCs were incubated with various concentrations of capsaicin. Cell proliferation was examined using a cell counting kit. Production of hydrogen peroxide was determined using a 2',7'-dichlorofluorescin diacetate (DCFH-DA) assay. The mRNA and protein expression of target genes was analyzed by reverse transcription PCR and Western blot analysis, respectively. Cell apoptosis was evaluated by annexin V-FITC and propidium iodide (PI) costaining followed by flow cytometric analysis. A CCl4 rat liver fibrosis model was used to assess in vivo effects of capsaicin by histological examination and measurement of liver fibrosis markers, including hydroxyproline content, serum type III collagen, and hyaluronic acid (HA) levels. Our results show that capsaicin dose-dependently inhibited cell proliferation, suppressed cell activation, and decreased hydrogen peroxide production in cultured HSCs. Capsaicin reduced the mRNA levels of tissue inhibitors of metalloproteinase 1 (TIMP-1) and transforming growth factor-ß1 (TGF-ß1) in HSCs. Moreover, capsaicin-induced cell apoptosis was associated with increased expression of Bax, cytochrome c (cyt c), and caspase-3, but reduced levels of Bcl-2. The animal studies further revealed that capsaicin efficiently reduced the extent of liver fibrosis, inhibited HSC proliferation, and promoted cell apoptosis. Our findings suggest that capsaicin might inhibit fibrogenesis by inhibiting the activities of HSCs.