New Therapy for Liver Disease by Platelets
Nobuhiro Ohkohchi, MD, PhD
Department of Surgery, University of Tsukuba, Japan
Series: Hepatology Research and Clinical Developments
Platelets contain many biological functional substrates of cytokines and growth factors, such as platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), transforming growth factor (TGF)-â, and so on. Recent studies have clarified that platelets have not only thrombotic effects but they also play important roles in promotion of liver regeneration, suppression of liver fibrosis and prevention of acute hepatitis.
In this chapter, specific platelet’s effects on liver is described as follows; I) promotion of liver regeneration, II) suppression of fibrosis in cirrhotic liver, III) prevention of hepatitis and IV) the clinical trial of platelet transfusion for the patients with liver cirrhosis. I) Platelets promote liver regeneration after hepatectomy and the proliferative effects of platelets are two different ways, i.e., the direct effect on hepatocytes and the indirect effect through liver sinusoidal endothelial cells. II) Platelets contribute to liver regeneration and the reduction of liver fibrosis even under the cirrhotic liver. III)
Liver damage with hepatitis C virus is well known to be induced by apoptosis with Fas-Fas ligand interaction. Increase of platelets has a preventative effect against acute hepatitis induced by Fas ligand. Platelets will be new therapeutic substrates for hepatic failure after liver surgery, liver cirrhosis, and acute hepatitis. Based on these results, we ran IV) the clinical trial of platelet transfusion therapy for liver cirrhosis. Platelet transfusion therapy improved liver function in patients with liver cirrhosis. Fatal adverse events were not observed during platelet transfusion therapy. Therefore, platelet increment therapy will be a new strategy for liver cirrhosis. Platelets are important for orchestration of liver regeneration, suppression of liver fibrosis, and prevention of acute hepatitis, therefore, control of the number of platelets will become a new therapy for various liver diseases instead of liver transplantation in future. (Imprint: Nova Biomedical )