Change from a hard to soft diet alters the expression of insulin-like growth factors,their receptors,and binding proteins in association with atrophy in adult mouse masseter muscle |
| |
Authors: | Toki?Urushiyama,Satonari?Akutsu,Jun-Ichi?Miyazaki,Tadayoshi?Fukui,Thomas?G.?H.?Diekwisch,Akira?Yamane author-information" > author-information__contact u-icon-before" > mailto:GAH@nifty.ne.jp" title=" GAH@nifty.ne.jp" itemprop=" email" data-track=" click" data-track-action=" Email author" data-track-label=" " >Email author |
| |
Affiliation: | (1) Masters Program in Biosystem Studies, University of Tsukuba, Tsukuba, Japan;(2) High Technology Research Center, Tsurumi University School of Dental Medicine, Yokohama, Japan;(3) Institute of Biological Sciences, University of Tsukuba, Tsukuba, Japan;(4) Department of Orthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan;(5) Brodie Laboratory for Craniofacial Genetics, Department of Orthodontics, University of Illinois College of Dentistry, Chicago, USA;(6) Department of Pharmacology, Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, 230–8501 Yokohama, Japan |
| |
Abstract: | To study the role of insulin-like growth factors (IGFs) in the atrophy of mouse masseter muscle in response to a change from a hard to a soft diet, we analyzed the amounts of mRNA and the immunolocalization for IGF-I, IGF-II, their receptors (IGFRs), and binding proteins (IGFBPs). Sixteen male ICR mice were fed a hard diet after weaning; they were divided into two groups at 6 months of age and fed a hard or a soft diet for 1 week. The soft diet treatment decreased masseter weight by 19% (P<0.01) and the minimal diameter of masseter myofibers by 19% (P<0.01), verifying that a soft diet led to atrophy of mouse masseter muscle. The soft diet treatment induced a 30% reduction in the amount of IGF-I mRNA (P<0.05) in preparations of whole masseter tissues. Immunohistochemical findings suggested that a reduction in the expression of IGF-I protein took place in the neural tissues, not in the masseter myofibers. The soft diet treatment induced a 56% decrease in IGF-II mRNA (P<0.05), a 21% increase in IGFR2 mRNA (P<0.01), and a 38% decrease in IGFBP5 mRNA (P<0.01). Immunohistochemical results suggested that these changes at the protein level occurred in the masseter myofibers. No significant or marked difference in the mRNA amount or immunostaining pattern for IGFR1, IGFBP3, IGFBP4, or IGFBP6 was found between the soft and hard diet groups. No IGFBP1 or IGFBP2 mRNA was detected. Thus, IGF-I, IGF-II, IGFR2, and IGFBP5 seem to play a role in the atrophy of mouse masseter muscle in response to the change from a hard to a soft diet in an autocrine and/or paracrine manner.Part of the present study was supported by a grant-in-aid for funding scientific research (no. 13671955), Bio-ventures and High-Technology Research Center, from the Ministry of Education, Culture, Sports, Science, and Technology of Japan |
| |
Keywords: | Masseter muscle Insulin-like growth factors (IGFs) IGF receptors IGF binding proteins Immunohistochemistry mRNA Hard/soft diet Mouse (male ICR) |
本文献已被 PubMed SpringerLink 等数据库收录! |
|