Human adipose-derived stem cells pre-treated with platelet-rich plasma and hepatocyte growth factor alleviate liver fibrosis in mice

Background: Transplantation of adipose-derived stem cells (ADSCs) is a potential therapy for a variety of liver diseases. Previous studies have shown that ADSC-based therapy is promising for liver fibrosis treatment. Recently, many publications have suggested that pretreating ADSCs with growth factors before transplantation can elevate the effectiveness of the therapy. Therefore, we hypothesize that human ADSCs (hADSCs) pre-treated with platelet-rich plasma (PRP) and hepatocyte growth factor (HGF), compared to ADSCs alone, would accelerate the treatment effects on liver fibrosis in mice. Methods: The hADSCs were cultured solely with conventional media, or with HGF (human recombinant; 20 ng/ml), or with HGF and PRP (from healthy human blood, 10%), concomitantly added to the medium for 7 days before transplantation. Eight-week-old male mice were treated with CCl4 (1 ml/kg) for 11 weeks to induce liver fibrosis. The mice were then subsequently divided into: 1) Placebo group (PBS injection); 2) ADSCs/HGF+PRP (5x10(5) HGF and PRP pre-treated cells/mice); 3) ADSCs/HGF (5x10(5) HGF pre-treated cells/mice) and 4) ADSCs (5x10(5) non-pretreated cells/mice). Results: Seven days post-transplantation, the alanine transaminase (ALT) level in the placebo was notably elevated (143.10 +/- 14.96 IU/L), compared to ALT levels of ADSCs-, ADSCs/HGF+PR-, and ADSCs/HGFtransplanted mice, which showed an improvement (67.94 +/- 18.57 IU/L, 49.44 +/- 7.56 IU/L, and 57.93 +/- 5.75 IU/L, respectively). The procollagen-alpha 1 and alpha-smooth muscle actin (alpha-SMA) mRNA levels were significantly down-regulated in the ADSCs-transplanted group compared to those of the placebo. Importantly, these levels were lower in ADSCs/HGF+PR (procollagen-alpha 1: 75.64 +/- 45.89; alpha-SMA: 36.17 +/- 36.09) than those of ADSCs/HGF (procollagen-alpha 1: 212.8 +/- 84.35; alpha-SMA: 52.41 +/- 7.93) and ADSCs only (procollagen-alpha 1: 310.50 +/- 55.36; alpha-SMA: 184.70 +/- 14.06). Stem cell transplantation also improved histological index, reducing inflammation and collagen/necrotic structure accumulation. However, there were no statistical differences between three ADSCs treatment groups after 14 days after transplantation. Conclusion: Pre-treatment with PRP and HGF for 7 days enhanced the efficacy of ADSCs in alleviating liver fibrosis in vivo.