Transplantation of human Wharton's Jelly-derived stem cells alleviates chemically induced liver fibrosis in rats.

There is currently no effective treatment method available for liver fibrosis. We therefore evaluated the use of Wharton's jelly stem cells (WJSCs; the major umbilical cord stem cell population) to treat chemically induced liver fibrosis via intraperitoneal injection of thioacetamide. WJSCs were transplanted into liver-damaged rats via the portal vein and the treatment was evaluated by assessing serum biochemistry and histopathology. Transplanted WJSCs were distributed in the fibrotic area and around blood vessels, and hepatic recovery was accelerated. Serum prothrombin time significantly recovered, and serum albumin also improved at 21 days posttransplantation; collagen accumulation also decreased at 14 days. Thus, human WJSCs promoted recovery after chronic liver damage. Using immunohistochemical analyses, we determined that transplanted WJSCs produce albumin, hepatocyte growth factor (HGF), and metalloproteinase (MMP) after transplantation to chemically injured liver, indicating that WJSC may help to decrease liver collagen and thus may be useful for treating liver fibrosis.

Mesenchymal stem cells facilitate recovery from chemically induced liver damage and decrease liver fibrosis.

AIMS: To investigate the feasibility and mechanism of liver damage repair using human bone marrow mesenchymal stem cells (hBMMSCs), we investigated the potential for hBMMSCs in recovery from liver damage, including fibrotic liver repair, using the CCl(4)-induced model for liver damage in the rat. MAIN METHODS: Rats were injected with 0.5 ml/kg CCl(4) to induce liver damage and progressive liver fibrosis. hBMMSCs labeled with GFP were injected into the rats through the portal vein. KEY FINDINGS: After one day of transplantation, GFP-labeled cells were found around the liver lobules, the hepatic blood vessels, and the edge of the liver lobes. Biochemical and histopathological analyses showed significantly increased recovery from liver damage in the transplanted group. In addition, transplanted hBMMSCs express matrix metalloproteinases (MMP), and liver fibrosis was significantly decreased. The degree of fibrosis reduction paralleled the number of hBMMSCs observed in liver sections. SIGNIFICANCE: Our data suggest that hBMMSCs may facilitate recovery from chronic liver damage and may decrease liver fibrosis. Therefore, hBMMSCs are a potential option for treatment of liver cirrhosis.

Effect of pulsed electromagnetic field on the proliferation and differentiation potential of human bone marrow mesenchymal stem cells.

Pulsed electromagnetic fields (PEMFs) have been used clinically to slow down osteoporosis and accelerate the healing of bone fractures for many years. The aim of this study is to investigate the effect of PEMFs on the proliferation and differentiation potential of human bone marrow mesenchymal stem cells (BMMSC). PEMF stimulus was administered to BMMSCs for 8 h per day during culture period. The PEMF applied consisted of 4.5 ms bursts repeating at 15 Hz, and each burst contained 20 pulses. Results showed that about 59% and 40% more viable BMMSC cells were obtained in the PEMF-exposed cultures at 24 h after plating for the seeding density of 1000 and 3000 cells/cm2, respectively. Although, based on the kinetic analysis, the growth rates of BMMSC during the exponential growth phase were not significantly affected, 20-60% higher cell densities were achieved during the exponentially expanding stage. Many newly divided cells appeared from 12 to 16 h after the PEMF treatment as revealed by the cell cycle analysis. These results suggest that PEMF exposure could enhance the BMMSC cell proliferation during the exponential phase and it possibly resulted from the shortening of the lag phase. In addition, according to the cytochemical and immunofluorescence analysis performed, the PEMF-exposed BMMSC showed multi-lineage differentiation potential similar to the control group.