Functional assessment of proliferating hepatocytes stimulated by hepatic stimulatory substance in ascorbic acid biosynthetic enzyme-deficient rats

✍ Scribed by F Nakazawa; M Sawa; B Jiang; K Onodera; S Kasai; M Mito

• Book ID: 102852024
• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 775 KB
• Volume: 26
• Category: Article
• ISSN: 0270-9139
• DOI: 10.1002/hep.510260226

✦ Synopsis

the possibility of metabolic support by HTx for animals with The functional ability of hepatic stimulatory substance congenital metabolic disorders. 1 We have already reported (HSS)-stimulated proliferating hepatocytes was investigated that transplanted syngeneic hepatocytes survived in the by intrasplenic and/or intraportal transplantation in ascorbic spleen for a long time, recomposing hepatic cord structure, acid (AsA) biosynthetic enzyme-deficient (ODS-od/od) rats and that they exhibited hepatocellular function by histothat die of osteogenic disorders unless there is AsA supplechemical study. 2 However, the time required for transplanted mentation. HSS was extracted from regenerating porcine livhepatocytes to exhibit sufficient hepatocellular function is ers. Hepatocytes isolated from the livers of congeneic ODStoo long for this modality to be used in experimental models /// rats that are capable of synthesizing AsA were of chronic hepatic failure and congenital metabolic disortransplanted into the spleen (Sp-HTx) and/or the portal vein (Pv-HTx) of ODS-od/od rats. The recipients were divided into ders. 1 eight groups as follows: HSS-untreated groups [group Ia,

The ODS-od/od rat is unable to synthesize ascorbic acid sham-operated, HTx(0); group IIa, Sp-HTx; group IIIa, Pv-(AsA) because of a congenital lack of L-gulonolactone oxidase HTx; and group IVa, Sp-and Pv-HTx], HSS-treated groups in the liver and dies of osteogenic disorders following severe [group Ib, HSS only; group IIb, Sp-HTx / HSS; group IIIb, weight loss and bleeding unless they are given exogenous Pv-HTx / HSS; and group IVb, Sp-and Pv-HTx / HSS]. The AsA. 3 Congeneic HTx into the spleen and the portal vein recipients were given a diet and water containing AsA for 6 improved the survival rate of ODS-od/od rats when the recipiweeks after HTx, and AsA supplementation was then halted. ent rats were pretreated with a hepatotoxin, 2-acetyl-The average bromodeoxyuridine (BrdU) labeling index (LI) aminofluorene, and a subsequent partial hepatectomy (PH) and hepatocyte-occupied ratio in the spleen (H/S ratio) of of 70%. 4 However, this pretreatment and PH cannot be ap-HSS-treated rats were significantly higher than those of HSSplied in patients with hepatic disorders. Therefore, a method untreated rats. All the rats in HSS-untreated groups and group of inducing immediate and rapid proliferation of transplanted Ib died by 8 weeks after the cessation of AsA. In HSS-treated hepatocytes is urgently needed. groups IIb, IIIb, and IVb, the survival rates were 60%, 50%, Hepatic stimulatory substance (HSS), which can be exand 80%, respectively, at 16 weeks after HTx. The average tracted from fetal, weanling, and regenerating livers, stimuserum AsA level of the surviving rats in groups IIb, IIIb, lates liver regeneration after PH and the proliferation of culand IVb was significantly higher than that in HSS-untreated tured hepatocytes. 5 We have already confirmed the beneficial groups. These results indicate that HSS treatment induced effect of HSS on the survival of intrasplenically transplanted rapid proliferation of transplanted hepatocytes in the spleen hepatocytes in normal rats 6 and on the proliferation of them and the portal vein, and that these proliferating hepatocytes in rats with experimentally induced liver cirrhosis. 7 The aim synthesized AsA and improved the survival rate of ODS-od/ of the study was to assess the functional ability of HSSod rats. (HEPATOLOGY 1997;26:437-443.) stimulated proliferating hepatocytes following intrasplenic and intraportal transplantation in ODS-od/od rats. Hepatocyte transplantation (HTx) has been studied to de-

Methods

velop an alternative therapy for hepatic failure and congenital metabolic disorders. The improvement in the survival rate Reagents. Type I collagenase and bromodeoxyuridine (BrdU) of animals with acute hepatic failure following HTx suggests were purchased from Sigma Chemical Co. (St. Louis, MO). BrdU monoclonal antibody was obtained from Becton Dickinson (Mountain View, CA). Avidin-biotinylated antimouse immunoglobulin G and Vectastain ABC kit were obtained from Vector Laboratories Abbreviations: HTx, hepatocyte transplantation; AsA, ascorbic acid; PH, partial (Burlingame, CA).