Glycyrrhizin (GL) is widely used in Japan as a therapeutic agent for chronic active liver diseases. However, its action on hepatocarcinogenesis remains to be elucidated. To clarify its effect, mice treated with diethylnitrosamine (NDEA) with or without GL were analyzed. Five-week-old male BALB/c mice were divided into two groups, GL (n=50) and C (n=47). Mice in the GL group intramuscularly received 2 mg of GL 3 days a week, and mice in the C group received the same volume of saline in the same way. After 2 weeks, the mice were treated with an i.p. injection of 75 mg/kg body wt of NDEA weekly for 3 weeks and 100 mg/kg body wt of NDEA weekly for the following 3 weeks. Thirty additional mice that did not receive NDEA treatment were divided into two groups, GC (n=15) and SC (n=15). They received GL or saline, respectively. Mice in the 4 groups were killed every 5 weeks after the last injection of NDEA from 7 weeks to 32 weeks. Liver function tests such as AST and albumin were significantly improved in the GL group compared with the C group (P < 0.05, each). Although liver nodules appeared in the C group at 22 weeks, they were not observed until 32 weeks in the GL group. At 32 weeks, the mean number of liver tumors, composed of adenoma and hepatocellular carcinoma (HCC), in the GL group was 0.71, which was significantly decreased compared with 1.64 of the C group (P < 0.05). The mean number of HCC in the GL group was 0.29/liver, which was lower than 0.82/liver in the C group (P < 0.05). The incidence rate of HCC at 32 weeks was 64% in the C group and 21% in the GL group (P < 0.05, C versus GL group). Our results suggest that GL treatment inhibits the occurrence of HCC.

Thrombocytopenia in liver diseases is considered to be due to splenic platelet pooling and accelerated destruction. Since thrombopoietin (TPO), a regulator of thrombopoiesis, is produced mainly in the liver, decreased production of TPO may account for thrombocytopenia in liver diseases. To address this issue, we measured serum TPO, using a sensitive sandwich ELISA, in 108 patients with chronic viral hepatitis, which included chronic hepatitis (CH) and liver cirrhosis (LC), and hepatocellular carcinoma (HCC), and in 29 normal controls. TPO mRNA in 78 liver samples was examined by reverse transcription (RT)-PCR. Platelet counts in CH, LC, HCC and controls were 176 +/- 15 x 10(9)/l, 81 +/- 8 x 10(9)/l, 99 +/- 7 x 10(9)/l and 234 +/- 9 x 10(9)/l respectively. Serum TPO levels in CH, LC and HCC were 2.79 +/- 0.4 fmol/ml, 1.49 +/- 0.2 fmol/ml and 1.97 +/- 0.2 fmol/ml, and were higher than those of controls. Serum TPO levels were positively correlated with prothrombin time and serum albumin (P < 0.05, in each case), and negatively correlated with Indocyanine Green test and Pugh score (P < 0.01 and P < 0.05 respectively). However, RT-PCR and immunohistochemistry showed that expression of TPO mRNA and protein were similar in the different liver diseases, suggesting that serum TPO is a reflection of the total mass of functional liver. Platelet counts were negatively correlated with spleen index, but not with serum TPO. These results suggest that thrombocytopenia in liver disease is not directly associated with serum TPO but is associated with hypersplenism.

No abstract

Thrombocytopenia in liver diseases is considered to be due to splenic platelet pooling and accelerated destruction. Since thrombopoietin (TPO), a regulator of thrombopoiesis, is produced mainly in the liver, decreased production of TPO may account for thrombocytopenia in liver diseases. To address this issue, we measured serum TPO, using a sensitive sandwich ELISA, in 108 patients with chronic viral hepatitis, which included chronic hepatitis (CH) and liver cirrhosis (LC), and hepatocellular carcinoma (HCC), and in 29 normal controls. TPO mRNA in 78 liver samples was examined by reverse transcription (RT)-PCR. Platelet counts in CH, LC, HCC and controls were 176 +/- 15 x 10(9)/l, 81 +/- 8 x 10(9)/l, 99 +/- 7 x 10(9)/l and 234 +/- 9 x 10(9)/l respectively. Serum TPO levels in CH, LC and HCC were 2.79 +/- 0.4 fmol/ml, 1.49 +/- 0.2 fmol/ml and 1.97 +/- 0.2 fmol/ml, and were higher than those of controls. Serum TPO levels were positively correlated with prothrombin time and serum albumin (P < 0.05, in each case), and negatively correlated with Indocyanine Green test and Pugh score (P < 0.01 and P < 0.05 respectively). However, RT-PCR and immunohistochemistry showed that expression of TPO mRNA and protein were similar in the different liver diseases, suggesting that serum TPO is a reflection of the total mass of functional liver. Platelet counts were negatively correlated with spleen index, but not with serum TPO. These results suggest that thrombocytopenia in liver disease is not directly associated with serum TPO but is associated with hypersplenism.

Summary.We measured serum thrombopoietin (TPO) in chronic hepatitis C treated with interferon (IFN). The platelet count before the therapy was 161 . 9 × 10 9 Ϯ 64 . 1 × 10 9 /l, which decreased to 116 . 3 × 10 9 Ϯ 48 . 4 × 10 9 /l 1 week after IFN therapy (P < 0 . 01). On the other hand, serum TPO increased from 1 . 96 Ϯ 0 . 60 fmol/ml to 2 . 68 Ϯ 0 . 69 fmol/ml (P < 0 . 02). Contrary to a recent report that serum TPO was not altered in liver cirrhosis, these data indicate that serum TPO was increased in chronic hepatitis C in response to thrombocytopenia by IFN therapy.