tetracycline and Starvation

To learn more about tissue remodelling in fibrotic livers of tetracycline-controlled TGF-beta1 transgenic mice (TGF-beta1-on-mice) and during regeneration after removal of the fibrotic stimulus (off-mice), we investigated the expression of glutamine synthetase (GS), an exclusive pericentrally expressed enzyme.. GS was localised immunohistochemically and quantified by real-time RT-PCR and enzymatic activity measurement. Apoptosis in livers of TGF-beta1-on-mice was demonstrated by in situ apoptosis detection kit (TUNEL reaction).. Livers of TGF-beta1-on-mice harbour a reduced number of GS-positive hepatocytes and expression of GS is downregulated, while multiple starved mice serving as controls for malnutrition during TGF-beta1 exposure surprisingly showed an impressive amplification of GS-positive hepatocytes. Apoptotic events were frequent around central veins in livers of TGF-beta1-on-mice, while in multiple induced mice apoptosis was dominant around all vessels and weak in midzonal areas. During regeneration from fibrosis, control levels were regained within 21 days. Beta-catenin was dislocated from plasma membrane to cytoplasm exclusively in pericentral hepatocytes during a short time slot after a unique expression of TGF-beta1.. Reduction of GS in TGF-beta1-on-mice results from apoptosis of GS-positive hepatocytes rather than downregulation of GS expression. Beta-catenin seems involved in the recovery of GS-positive hepatocytes.

Topics: Animals; Anti-Bacterial Agents; Apoptosis; beta Catenin; Cell Division; Cytoskeletal Proteins; Gene Expression; Glutamate-Ammonia Ligase; Liver; Liver Cirrhosis; Liver Regeneration; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Mice, Transgenic; RNA, Messenger; Starvation; Tetracycline; Trans-Activators; Transforming Growth Factor beta; Transforming Growth Factor beta1

Topics: Acinetobacter; Animals; Cortisone; Escherichia coli; Female; Flavobacterium; Immunization; Lung; Mice; Organ Size; Proteus; Pseudomonas; Starvation; Tetracycline