Objective To investigate the actions of apoptotic pathways in rat liver regeneration(LR) at the transcription level.Methods The apoptosis genes were obtained by referring to the putative literatures and databases.Apoptotic-related genes expression profiles in rat LR were checked by Rat Genome 230 2.0 array.Identification of LR-associated genes was made by comparing the discrepancies of genes expression between partial hepatectomied(PH) and sham operatied(SO) rats.Results 252 genes were found to be related to liver regeneration.The initial and total expressing gene numbers occurring in the initiation phase of liver regeneration(0.5-4hours after PH),G_0/G_1 transition(4-6hours after PH),cell proliferation(6-66hours after PH),cell differentiation and structure-function reconstruction(72-168hours after PH) were 81,23,155,16 and 161,100,733,192 respectively.This demonstrated that LR-related genes primarily started their expression in the initiation phase,and worked in the different phases.The total times of their up-and down-regulated expression were 795 and 291,demonstrating that expression of most genes was enhanced in LR.Their expression patterns could be classified into 35 types,indicating the expressions of apoptosis-related genes in LR were diverse and complicated.Conclusion There are fifteen kinds of apoptosis pathways that associate to apoptosis regulation in the regenerating liver.

Hepatic oval cells (OCs) are the stem cells of the liver. They can differentiate into liver cells, bile duct epithelial cells and other cells, and also are closely related to liver regeneration and liver diseases. In this article, we give a brief summary focused on the source, location, proliferation, differentiation, apoptosis, transplantation of hepatic oval cells, and its role in liver regeneration and liver diseases.

Pit cells (PCs) are hepatic natural killer cells(HNKCs), and play an important role in resisting tumor, resisting virus, regulating hepatocyte growth and differentiation, inhibiting liver fibrosis and so on. In the paper, research progress in liver pit cells is briefly summarized.

Hepatic stellate cells (HSCs) are a group of nonparenchymal cells of liver, and play an important role in lipid, especially vitamin A-storing, extracellular matrix synthesis, microcirculation regulation of hepatic sinusoid, etc. They are also closely related to lots of liver diseases, e. g. hepatofibrosis. In this review, the latest research advance on HSCs including their isolation, identification, proliferation and regulation, and role in liver regeneration, hepatofibrosis, and so on is summarized.

Kupffer cell is a member of the liver nonparenchymal cells, it participates in a variety of physiological activities through phagocytosis, secreting cytokines, antigen-presenting pathways, and is closely related to a variety of diseases such as liver cancer, liver fibrosis, liver injury. This paper presents the progress of research on physiological functions of kupffer cells and its relations with liver.

Objective To study the expression changes and patterns of nucleic acid and their derivative metabolism,processing and transport-related genes in rat liver regeneration(LR) at transcriptional level. Methods The related genes were obtained by online data collection and literature review,and gene expression patterns in rat regenerated liver were checked by Rat Genome 230 2.0 array.LR-related genes were identified through the comparison of discrepancles in gene expression between partial hepatectomy(PH) and sham operation(SO) groups. Results 240 genes were determined to be related with liver regeneration.The number of initially expressive genes in the forepart of liver regeneration(0.5-4 hours after PH),prophase(6-12 hours after PH),metaphase(16-66 hours after PH),anaphase(72-168 hours after PH) were 65,14,150,11 respectively and the total expression numbers were 133,87,627,169 respeitirely.There were 6,5,22 and 9 expression patterns.Frequencies of up-regulation and down-regulation were 768 and 248.mRNA catabolism in prophase and metaphase,DNA recombination,modification and transcript,mRNA processing and transport in prophase,metaphase and anaphase,and nucleotides and their derivatives metabolism,as well as DNA replication,packaging and catabolism during the whole LR,were enhanced.Conclusion LR-related genes were mainly triggered in the forepart of liver regeneration,and funclioned at different phases.

Objective To study the expression changes of transcription factor genes and their underlying involvement in rat liver regeneration(LR) at transcription level. Methods The transcription factor genes and their function were collected by referring to the putative literatures and databases.Then,their expression in rat LR were checked by Rat Genome 230 2.0 array.LR-related genes were identified through the comparison of discrepancies in gene expression between partial hepatectomy(PH) and sham-operation(SO) groups. Results 320 genes were determined to be LR-related,which were involved in 16 biological processes,such as cellular metabolism,proliferation,differentiation,apoptosis,etc.Expression profiles of above genes were classified into 41 categories according to their functions and expression trends,implying their diversity and complexity during LR.The expression of transcription factor genes that were involved in carbohydrate biosynthesis,lipid metabolism,and inflammatory response was enhanced in the forepart(0.5-4 hours after PH) and prophase(6-12 hours after PH) of LR.Cellular proliferation,growth,differentiation and apoptosis related transcription factor genes were promoted in the metaphase(16-66 hours after PH) and anaphase(72-168 hours after PH).Conclusion Physiological and biochemical activities in LR were regulated by multiple transcription factor genes,and e2f1,fos,copeb,etc.played key roles in it.

Objective To study the regulating effect of in the regulation of cell surface receptor linked signal transduction pathway-related genes on rat liver regeneration(LR) at transcriptional level. Methods Genes involved in the above pathways were obtained by data collection and literature review.The gene expression changes during LR were checked by Rat Genome 230 2.0 array,and LR-related genes were identified by comparing gene expression difference between partial hepatectomy(PH) and sham operation(SO) groups. Results 491 genes were identified as LR-related.There were 742 kinds of interactive relations in 226 before-mentioned genes.In the 12 kinds of signaling pathways cytokine and chemokine mediated,enzyme linked receptor,G-protein coupled receptor,glutamate,antigen receptor-mediated,integrin-mediated,lipopolysaccharide-mediated, Notch,osmosensory,smoothened,Toll and Wnt——the numbers of up-regulated and down-regulated LR-related genes were 26 and 23,164 and 54,59 and 51,5 and 1,22 and 14,21 and 10,1 and 1,4 and 11,23 and 11, 32 and 17 respectively.In LR,the numbers of up-regulated and the down-regulated genes were 188 and 128,464 and 190,308 and 207,13 and 5,88 and 46,123 and 50,2 and 1,20 and 43,148 and 30,174 and 62 in the corresponding pathways.The genes which up regulated mainly occurred 0.5-16,30,42,54,96 hours and which down regulated mainly occurred 18-24,36,60-72,120-168 hours.Conclusion In liver regeneration,lipopolysaccharide-mediated and osmosensory signaling pathway have less effect,and the smoothened signaling pathway's role is attenuated,but the activities of the other 9 pathways are enhanced.

Objective To study the expression changes and profiles of nuclear structure and biogenesis-related genes in rat liver regeneration(LR). Methods Genes involved in nuclear structure and biogenesis were obtained by data collection and literature review.The gene expression changes during LR were checked by Rat Genome 230 2.0 array,and LR-related genes were identified by comparing gene expression difference between partial hepatectomy(PH) and sham operation(SO) groups.Results 406 genes were found to be LR-related.The numbers of initially and totally expressed genes occurring in the forepart(0.5-4 hours after PH) of LR,the prophase(6-12 hours after PH),the metaphase(12-66 hours after PH),and the anaphase(72-168 hours after PH) were 200,29,179,5 and 374,290,1?876,603,respectively.The numbers of their up-regulation and down-regulation were 1?224 and 496 times.The elevated transcription levels occur red to the nuclear organization and biogenesis-involved genes in the prophase and the metaphase of LR and to the nuclear membrane,nuclear matrix and nucleoplasm-involved genes in the metaphase;nuclear chromosome,nucleolus and nuclear functional protein complex-involved genes were up-regulated in the metaphase and the anaphase.Conclusion The expression of nuclear structure and biogenesis-related genes was active during LR,and it was tightly related with LR.

Objective To investigate the possible contribution of PPAR-? coupled signaling pathways to rat liver regeneration (LR) at transcription level.Methods The above signaling pathways-related genes were obtained by collecting database data and retrieving pertinent literatures. The gene expression during LR was checked by Rat Genome 230 2.0 array, and LR-associated genes were identified by comparing difference between partial hepatectomy (PH) and operation control (OC) groups.Results Sixty four genes were found to be LR-associated. The number of initially and totally expressed genes occurring in initiation phase of LR, G0/G1 transition, cell proliferation, cell differentiation and structure-function reconstruction was 28, 4, 34, 2 and 72, 41, 247, 90 respectively. Classification of their expression patterns into 11 groups reflected diversity and complexity of gene expression alteration in LR. Conclusion PPAR-? coupled signaling pathways may promote glycogen synthesis in forepart, prophase and anaphase of LR, cell proliferation and migration in the whole LR, while inhibits inflammation during LR.