Modulation of gene expression of SMP-30 by LPS and calorie restriction during aging process.
Senescence marker protein-30 (SMP-30) has been proposed as an important aging marker and is now functionally identified as a Ca2+ binding protein. SMP-30 has been shown to blunt cell death caused by intracellular Ca2+ accumulation by enhancing plasma membrane Ca(2+)-pumping activity. Although SMP-30 is reported decrease during aging, at present, neither has the mechanism underlying this decrease been fully defined, nor have the mechanisms related to the modulation of SMP-30 been extensively explored. In the current study, we used the well-known anti-aging action of the calorie restriction (CR) paradigm to explore age-related changes in SMP-30 gene expression. The thrust of our investigation was based on CR's ability to defend against age-related oxidative stress and the inflammatory process. The kidney and liver from Fischer 344 rats at 6, 12, 18 and 24 months of age were utilized for this study. The rats were divided into two groups, ad libitum (AL)-fed and 40% restricted CR. Results showed that SMP-30 expression declined with age and that this decline was clearly blunted by CR. To correlate changes between SMP-30 gene expression and the oxidative status, SMP-30 expression and the production of reactive oxygen species (ROS) during aging and free-radical generating lipopolysaccharide (LPS) were monitored. Our data showed that the down-regulation of SMP-30 was accompanied by increased ROS generation and LPS-induced ROS. The potent anti-aging and anti-oxidative action of CR effectively suppressed the age-related down-regulation of SMP-30 by ROS reduction.
Department of Pharmacy, Aging Tissue Bank, Pusan National University, Gumjung-ku, Busan 609-735, Republic of South Korea.
Kyung Jin
KJ
Jung
Akihito
A
Ishigami
Naoki
N
Maruyama
Ryoya
R
Takahashi
Sataro
S
Goto
Byung Pal
BP
Yu
Hae Young
HY
Chung
D000375:Aging / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D031204:Caloric Restriction; D005609:Free Radicals / Q000378:metabolism; D005786:Gene Expression Regulation; D006706:Homeostasis; D007668:Kidney / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008099:Liver / Q000378:metabolism; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D017382:Reactive Oxygen Species / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013047:Specific Pathogen-Free Organisms; D015238:Sulfotransferases
D002135:Calcium-Binding Proteins; D005609:Free Radicals; D008070:Lipopolysaccharides; D017382:Reactive Oxygen Species; D015238:Sulfotransferases; C028152:alcohol sulfotransferase; D002118:Calcium