Hepatic regeneration in peroxisome proliferator-activated receptor α-null mice after partial hepatectomy

M. Sambasiva Rao, Jeffrey Maurice Peters, Frank J. Gonzalez, Janardan K. Reddy

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Peroxisome proliferator activated receptor α (PPARα), a member of the nuclear hormone receptor superfamily, is essential for hepatic pleiotropic effects induced by peroxisome proliferators including cell proliferation. In a previous study, we have shown that PPARα null mice do not show increased hepatocyte proliferation after administration of peroxisome proliferators, confirming that PPARα is necessary for peroxisome proliferator-induced cell proliferation. However, the role of PPARα, if any, in compensatory liver cell hyperplasia is not known. Therefore, we examined the role of PPARα in modulating compensatory liver cell proliferation occurring after partial hepatectomy (PH). Replicative DNA synthesis, as measured by bromodeoxyuridine labeling of liver cell nuclei, was significantly higher after 48 h post-hepatectomy in both wild type and PPARα-null mouse livers, as compared to sham-operated control mice. Interestingly, in PPARα-null mice labeling index was significantly higher at 60 h after hepatectomy compared to wild-type mice; however, at 72 and 84 h the values were comparable in both the groups. Hepatic levels of mRNAs encoding CDK1, CDK2, CDK4, cyclin B1, cyclin D1 and PCNA were all elevated at 60 and 72 h post-hepatectomy and this effect was similar in both PPARα genotypes. Similarly, CDK2, CDK4, cyclin B1, cyclin D1 and PCNA proteins also showed comparable increase in both the groups. These results show that PPARα receptor is not essential for increased expression of CDKs, cyclins, PCNA and enhanced cell proliferation that occur after PH. This strongly suggests that the signaling for increased cell proliferation in response to PH is distinctly different from that observed after administration of peroxisome proliferators.

Original languageEnglish (US)
Pages (from-to)52-57
Number of pages6
JournalHepatology Research
Volume22
Issue number1
DOIs
StatePublished - Mar 25 2002

Fingerprint

Peroxisome Proliferator-Activated Receptors
Hepatectomy
Regeneration
Peroxisome Proliferators
Liver
Cell Proliferation
Proliferating Cell Nuclear Antigen
Cyclin B1
Cyclin D1
Cyclins
Bromodeoxyuridine
Cytoplasmic and Nuclear Receptors
Cell Nucleus
Hyperplasia
Hepatocytes
Genotype
Messenger RNA
DNA

All Science Journal Classification (ASJC) codes

  • Hepatology
  • Infectious Diseases

Cite this

Rao, M. Sambasiva ; Peters, Jeffrey Maurice ; Gonzalez, Frank J. ; Reddy, Janardan K. / Hepatic regeneration in peroxisome proliferator-activated receptor α-null mice after partial hepatectomy. In: Hepatology Research. 2002 ; Vol. 22, No. 1. pp. 52-57.
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Hepatic regeneration in peroxisome proliferator-activated receptor α-null mice after partial hepatectomy. / Rao, M. Sambasiva; Peters, Jeffrey Maurice; Gonzalez, Frank J.; Reddy, Janardan K.

In: Hepatology Research, Vol. 22, No. 1, 25.03.2002, p. 52-57.

Research output: Contribution to journalArticle

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