TY - JOUR
T1 - Impaired phorbol ester-induced hepatocyte proliferation in cirrhosis
AU - Imanishi, Hiroaki
AU - Kothary, Piyush C.
AU - Bhora, Faizullah Y.
AU - Eckhauser, Frederic E.
AU - Raper, Steven E.
PY - 1995/4
Y1 - 1995/4
N2 - Cirrhotic livers are considered to regenerate less actively than normal livers after hepatic resection. Little is known about the mechanisms responsible for impaired capacity of regeneration in cirrhotic liver. In the present study, we investigated the effect of phorbol ester on hepatocyte proliferation in healthy and cirrhotic hepatocytes, using one of the phorbol esters, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), which has a direct effect on activation of protein kinase C (PKC). Cirrhosis was established by the administration of carbon tetrachloride and phenobarbital to rats. Healthy and cirrhotic hepatocytes were isolated from Wistar male rats by a two-step collagenase perfusion technique. DNA synthesis was estimated by [3H]thymidine incorporation into DNA and by autoradiographic nuclear labeling index. [3H]Thymidine incorporation was measured 24 hr after hepatocytes were stimulated by appropriate reagents. TPA (50 nM) stimulated [3H]thymidine incorporation in healthy hepatocytes (control vs TPA, 991 ± 247 vs 2569 ± 766 mean ± SEM cpm/μg DNA; P < 0.05), whereas TPA (50 nM) failed to stimulate in cirrhotic hepatocytes (control vs TPA, 1144 ± 184 vs 1304 ± 187 cpm/μg DNA; NS). Staurosporine, a specific PKC inhibitor, suppressed [3H]thymidine incorporation in TPA-stimulated healthy hepatocytes (806 ± 263 cpm/μg DNA; P ± 0.05); however, it had no effect on cirrhotic hepatocytes (1295 ± 180 cpm/μg DNA; NS). An autoradiographic nuclear labeling index exhibited the same results with [3H]thymidine incorporation. We conclude that TPA stimulates hepatocyte proliferation in healthy rat hepatocytes but has no effect on cirrhotic hepatocytes.
AB - Cirrhotic livers are considered to regenerate less actively than normal livers after hepatic resection. Little is known about the mechanisms responsible for impaired capacity of regeneration in cirrhotic liver. In the present study, we investigated the effect of phorbol ester on hepatocyte proliferation in healthy and cirrhotic hepatocytes, using one of the phorbol esters, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), which has a direct effect on activation of protein kinase C (PKC). Cirrhosis was established by the administration of carbon tetrachloride and phenobarbital to rats. Healthy and cirrhotic hepatocytes were isolated from Wistar male rats by a two-step collagenase perfusion technique. DNA synthesis was estimated by [3H]thymidine incorporation into DNA and by autoradiographic nuclear labeling index. [3H]Thymidine incorporation was measured 24 hr after hepatocytes were stimulated by appropriate reagents. TPA (50 nM) stimulated [3H]thymidine incorporation in healthy hepatocytes (control vs TPA, 991 ± 247 vs 2569 ± 766 mean ± SEM cpm/μg DNA; P < 0.05), whereas TPA (50 nM) failed to stimulate in cirrhotic hepatocytes (control vs TPA, 1144 ± 184 vs 1304 ± 187 cpm/μg DNA; NS). Staurosporine, a specific PKC inhibitor, suppressed [3H]thymidine incorporation in TPA-stimulated healthy hepatocytes (806 ± 263 cpm/μg DNA; P ± 0.05); however, it had no effect on cirrhotic hepatocytes (1295 ± 180 cpm/μg DNA; NS). An autoradiographic nuclear labeling index exhibited the same results with [3H]thymidine incorporation. We conclude that TPA stimulates hepatocyte proliferation in healthy rat hepatocytes but has no effect on cirrhotic hepatocytes.
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U2 - 10.1006/jsre.1995.1068
DO - 10.1006/jsre.1995.1068
M3 - Article
C2 - 7723325
AN - SCOPUS:0028936139
SN - 0022-4804
VL - 58
SP - 435
EP - 440
JO - Journal of Surgical Research
JF - Journal of Surgical Research
IS - 4
ER -