Effects of aging and caloric restriction on IGF-I, IGF-I receptor, IGFBP-3 and IGFBP-4 gene expression in the rat stomach and colon
Effects of aging and caloric restriction on IGF-I, IGF-I receptor, IGFBP-3 and IGFBP-4 gene expression in the rat stomach and colon
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DOI：
10.1016/s0167-0115(00)00095-1
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发表时间：
2000-05-10
影响因子：
--
通讯作者：
Greeley, GH
中科院分区：
文献类型：
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作者：
Hallberg, LM;Ikeno, Y;Greeley, GH
本研究的目的是确定衰老和热量限制 (CR) 对雄性 Fischer 344 大鼠胃和结肠中胰岛素样生长因子-I (IGF-I)、IGF-I 受体 (IGF-IR)、IGF 结合蛋白-3 (IGFBP-3) 和 IGFBP-4 表达的影响。从随意 (AL) 喂养或长期 CR 的大鼠中制备胃和结肠 RNA。老年AL大鼠胃IGF-I、IGFBP-3和IGFBP-4 mRNA水平显着增加（P小于或等于0.05），而结肠IGF-I mRNA水平无变化。在老年 CR 大鼠中，胃 IGFBP-3 mRNA 水平下降。 AL和CR大鼠的胃和结肠IGF-IR mRNA水平随着年龄的增长而下降（P小于或等于0.05）。 AL 大鼠结肠 IGFBP-3 mRNA 水平随着年龄的增长而显着下降。老年 AL 或 CR 大鼠结肠 IGFBP-4 mRNA 水平没有变化。老年 AL 大鼠胃 IGF-I、IGFBP-3 和 IGFBP-4 表达增加表明胃试图通过增加 IGF-I 和 IGFBP 的局部表达来保持 IGF 活性。由于衰老的结肠有发生癌症的倾向，因此它可能通过减少 IGF-IR 和 IGFBP-3 的表达来适应结肠 IGF-I 表达的增加。此外，CR 降低老年大鼠（24 个月）的结肠 IGF-I 表达，这也可能是一种保护性适应性机制。 (C) 2000 爱思唯尔科学 BN。版权所有。
The purpose of this study was to determine the effects of aging and caloric restriction (CR) on insulin-like growth factor-I (IGF-I), IGF-I receptor (IGF-IR), IGF-binding protein-3 (IGFBP-3) and IGFBP-4 expression in the stomach and colon of male Fischer 344 rats. Stomach and colonic RNA were prepared from ad libitum (AL) fed or long-term CR rats. Stomach IGF-I, IGFBP-3 and IGFBP-4 mRNA levels increased significantly (P less than or equal to 0.05), while colonic IGF-I mRNA levels were unchanged in aged AL rats. In aged CR rats, stomach IGFBP-3 mRNA levels decreased. Stomach and colonic IGF-IR mRNA levels declined with aging in AL and CR rats (P less than or equal to 0.05). Colonic IGFBP-3 mRNA levels decreased significantly with aging in AL rats. There were no changes in colonic IGFBP-4 mRNA levels in aged AL or CR rats. Increased expression of stomach IGF-I, IGFBP-3 and IGFBP-4 in aged AL rats suggests that the stomach attempts to preserve IGF activity by increasing local expression of IGF-I and IGFBPs. Because the aging colon has a propensity to develop cancer, it may adapt to increased colonic IGF-I expression by reducing IGF-IR and IGFBP-3 expression. Additionally, CR lowers colonic IGF-I expression in aged rats (24 months) which may also be a protective adaptive mechanism. (C) 2000 Elsevier Science BN. All rights reserved.