title: Heat Resistant Characteristics of Major Royal Jelly Protein 1 (MRJP1) Oligomer.
abstract: Soluble royal jelly protein is a candidate factor responsible for mammiferous cell proliferation. Major royal jelly protein 1 (MRJP1), which consists of oligomeric and monomeric forms, is an abundant proliferative protein in royal jelly. We previously reported that MRJP1 oligomer has biochemical heat resistance. Therefore, in the present study, we investigated the effects of several heat treatments (56, 65 and 96°C) on the proliferative activity of MRJP1 oligomer. Heat resistance studies showed that the oligomer molecular forms were slightly maintained until 56℃, but the molecular forms were converted to macromolecular heat-aggregated MRJP1 oligomer at 65℃ and 96℃. But, the growth activity of MRJP1 oligomer treated with 96°C was slightly attenuated when compared to unheated MRJP1 oligomer. On the other hand, the cell proliferation activity was preserved until 96℃ by the cell culture analysis of Jurkat cells. In contrast, those of IEC-6 cells were not preserved even at 56°C. The present observations suggest that the bioactive heat-resistance properties were different by the origin of the cells. The cell proliferation analysis showed that MRJP1 oligomer, but not MRJP2 and MRJP3, significantly increased cell numbers, suggesting that MRJP1 oligomer is the predominant proliferation factor for mammiferous cells.
authors.affiliation: Faculty of Health Sciences, Hokkaido University, Kita-ku, Sapporo, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Moriyama
authors.affiliation: Division of Clinical Laboratories, Toranomon Hospital, Kawasaki, Japan.
authors.forename: Aimi
authors.initials: A
authors.lastname: Ito
authors.affiliation: Graduate School of Health Sciences, Hokkaido University, Kita-ku, Sapporo, Japan.
authors.forename: Sumire
authors.initials: S
authors.lastname: Omote
authors.affiliation: Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Miura
authors.affiliation: Research Team for Mechanism of Aging, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Tsumoto
mesh_terms: D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D005227:Fatty Acids / Q000378:metabolism*; D006023:Glycoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006358:Hot Temperature; D006801:Humans; D019476:Insect Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019169:Jurkat Cells; D051381:Rats; D000099219:Royal Jelly
chemical_list: D005227:Fatty Acids; D006023:Glycoproteins; D019476:Insect Proteins; D000099219:Royal Jelly