P2Y2 purinergic receptor activation is essential for efficient hepatocyte proliferation in response to partial hepatectomy.

Extracellular nucleotides via activation of P2 purinergic receptors influence hepatocyte proliferation and liver regeneration in response to 70% partial hepatectomy (PH). Adult hepatocytes express multiple P2Y (G protein-coupled) and P2X (ligand-gated ion channels) purinergic receptor subtypes. However, the identity of key receptor subtype(s) important for efficient hepatocyte proliferation in regenerating livers remains unknown.

Redundant roles for cJun-N-terminal kinase 1 and 2 in interleukin-1beta-mediated reduction and modification of murine hepatic nuclear retinoid X receptor alpha.

Background/aims: Retinoid X receptor alpha (RXRalpha), the heterodimeric partner for multiple nuclear receptors (NRs), was shown to be an essential target for inflammation-induced cJun-N-terminal kinase (JNK) signaling in vitro. This study aimed to explore the role of hepatic JNK signaling and its effects on nuclear RXRalpha levels downstream of interleukin-1beta (IL-1beta) in vivo.

Methods: Effects of IL-1beta on hepatic NR-dependent gene expression, nuclear RXRalpha levels, and roles for individual JNK isoforms were studied in wild-type, Jnk1(-/-), and Jnk2(-/-) mice and in primary hepatocytes of each genotype.

Mild hypothermia does not affect liver regeneration after partial hepatectomy in mice.

Background: The use of mild hypothermia has been suggested to be therapeutically useful in treating acute liver failure. It is not known if hypothermia influences liver regeneration.

Aim: To assess the effect of hypothermia on liver regeneration in mice.

Extracellular ATP activates c-jun N-terminal kinase signaling and cell cycle progression in hepatocytes.

Partial hepatectomy leads to an orchestrated regenerative response, activating a cascade of cell signaling events necessary for cell cycle progression and proliferation of hepatocytes. However, the identity of the humoral factors that trigger the activation of these pathways in the concerted regenerative response in hepatocytes remains elusive. In recent years, extracellular ATP has emerged as a rapidly acting signaling molecule that influences a variety of liver functions, but its role in hepatocyte growth and regeneration is unknown.

[Construction of antisense telomerase hTERT and its effect on K562 cells].

Objectives: To investigate whether antisense human telomerase reverse transcriptase (hTERT) could inhibit the activity of telomerase and the proliferation of K562 cells.

Methods: The antisense plasmid was constructed by reverse insertion of hTERT PCR product into plasmid pLNCX-neo. Then the constructed plasmid was introduced into K562 cells by liposomes-mediated DNA transfection.