Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019209 (hepatomegaly)
 5,798 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of long-term administration of nafenopin, a potent hypolipidemic drug with marked hepatomegalic and peroxisome-proliferative properties, were studied in wild-type (Csa strain) and acatalasemic (Csb strain) mice. Nafenopin was administered in the diet at a concentration of 0.1% during the first 12 months and then at 0.05% until the termination of the experiment at 20 months. By 56 weeks, 100% mortality occurred in both male and female wild-type mice, whereas the mortality rate in acatalasemic mice was approximately 50%. Between 18 and 20 months of the experiment, 9 of 9 male and 12 of 12 female acatalasemic mice that survived chronic nafenopin treatment developed hepatocellular carcinomas, some of which metastasized to the lungs. None of the 15 male and 15 female acatalasemic controls developed liver cancers. Numerous peroxisomes were seen in the lung metastases of these hepatocellular carcinomas on electron microscopic examination; in contrast the number of peroxisomes in primary liver tumor cells varied considerably. The hepatocarcinogenicity of nafenopin strongly suggests the need for long-term studies with other hypolipidemic drugs that cause hepatomegaly and peroxisome proliferation to clarify the role, if any, of peroxisome proliferation in liver carcinogenesis.
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PMID:Hepatocellular carcinomas in acatalasemic mice treated with nafenopin, a hypolipidemic peroxisome proliferator. 17 2

The mitogenic effect of Nafenopin, a hypolipidemic hepatic peroxisome proliferator, in mouse liver has been studied in acute and chronically treated mice. After 1, 6 and 32 weeks of treatment, the total hepatic DNA was increased 1.5-2.0-fold over controls. Mitotic and labeling indices were also increased 3-4 fold after 5 days, 6 weeks and 32 weeks of treatment. The increased mitotic activity in nafenopin fed animals was not associated with liver cell necrosis. The nafenopin induced hepatomegaly therefore appears to arise from a combination of cell proliferation, as well as, cellular hypertrophy, which is associated with peroxisome proliferation.
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PMID:Mitogenic effect in mouse liver induced by a hypolipidemic drug, nafenopin. 40 52

The mitogenic effects of peroxisome proliferating agents have been implicated in their carcinogenicity. WY-14,643 stimulates an increase in hepatocellular DNA replication that persists with continued administration, but it is unclear if other peroxisome proliferators share this property. In these studies, WY-14,643 was compared to clofibric acid, nafenopin and LY171883 given to rats in the diet for up to 30 days. DNA replication in the rat liver was quantified by immunohistochemical methods after continuous s.c. infusion of bromodeoxyuridine by osmotic minipump. During the first 7 days of treatment, WY-14,643 (0.1% in diet) and nafenopin (0.05%) increased the percentage of bromodeoxyuridine-labeled hepatocytes to greater than 50%, from 3% in controls. Clofibric acid (0.5%) and LY171883 (0.3%) increased the labeling to approximately 33%. The replicative response to each of the compounds was localized primarily to the periportal region of the liver lobule. The time-course of replication induced by clofibric acid and WY-14,64.3 was examined over 3 day intervals. The peak of replication in response to clofibric acid occurred during days 4-6, whereas the effect of WY-14,643 peaked during days 1-3 and was much greater than clofibric acid. The replicative response to WY-14,643 persisted through 30 days at dietary concentrations of 0.1 and 0.005%. Nafenopin, LY171883 and clofibric acid were without effect on DNA replication on days 28-30 even though the hepatomegaly and induction of peroxisomal beta-oxidation persisted. Thus, under the conditions of these experiments, the persistent replicative effect through 30 days was unique to WY-14,643. Although sustained replication in the general population of hepatocytes may be involved in the carcinogenesis of WY-14,643, it does not appear to be a factor in the hepatocarcinogenesis of the other peroxisome proliferators.
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PMID:Hepatocellular DNA synthesis in rats given peroxisome proliferating agents: comparison of WY-14,643 to clofibric acid, nafenopin and LY171883. 189 15