title: Age-associated decrease of senescence marker protein-30/gluconolactonase in individual mouse liver cells: Immunohistochemistry and immunofluorescence.
abstract: OBJECTIVE
  Senescence marker protein-30 (SMP30)/gluconolactonase (GNL) is an age-associated protein in that its presence decreases with aging. Here, we used immunohistochemical analysis to investigate the changes of SMP30/GNL in individual cells of the liver from progressively aged mice.
  
  
  METHODS
  Male C57BL/6 strain mice at 1, 3, 6, 12, 24 and 30 months-of-age were the source of hepatic cells used to detect SMP30/GNL. Liver sections from these mice were subjected to immunohistochemical staining with anti-SMP30/GNL antibody. For immunofluorescent staining, primary cultured hepatocytes from mice at various ages were stained with SMP30/GNL and albumin.
  
  
  RESULTS
  In liver cells from mice of all ages, SMP30/GNL staining appeared in some but not all parenchymal cells, and localized in both the nuclei and cytoplasm. Moreover, SMP30/GNL-positive staining of parenchymal cells was present only around central vein areas, but not at sites of portal veins. Furthermore, the number of SMP30/GNL-positive cells increased as mice aged from 1 to 12 months, then decreased from the 12th to 24th month. Results were similar in primary cultured hepatocytes from mice of various ages.
  
  
  CONCLUSIONS
  SMP30/GNL-positive cells localized mainly around the central veins in the livers of mice and decreased numerically with aging, although there was no age-related change in counts of albumin-positive cells. SMP30/GNL protein occupied the nuclei and cytoplasm. Therefore, nuclear SMP30/GNL protein might be a regulatory factor specific for genes whose expression governs transcription and the aging process.
authors.affiliation: Molecular Regulation of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Ishigami
authors.affiliation: Molecular Regulation of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Masutomi
authors.affiliation: Molecular Regulation of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Setsuko
authors.initials: S
authors.lastname: Handa
authors.affiliation: Molecular Regulation of Aging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Maruyama
mesh_terms: D000375:Aging / Q000235:genetics*; D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D022781:Hepatocytes / Q000378:metabolism*; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D019913:Nuclear Localization Signals / Q000235:genetics; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D002135:Calcium-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; D019913:Nuclear Localization Signals; C513324:Rgn protein, mouse; D002265:Carboxylic Ester Hydrolases; C020579:gluconolactonase; D001616:beta-Galactosidase
keywords: aging; gluconolactonase; hepatocyte; nuclear localization signals; senescence marker protein-30