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121 results on '"Koyama, Yoh-ichi"'

9. Comparative study of dermal components and plasma TGF-β1 levels in Slc39a13/Zip13-KO mice

Author

HIROSE, Takuya, OGURA, Takayuki, TANAKA, Keisuke, MINAGUCHI, Jun, YAMAUCHI, Takeshi, FUKADA, Toshiyuki, KOYAMA, Yoh-ichi, and TAKEHANA, Kazushige

Subjects
plasma TGF-β1 level, dermatan sulfate, Zip13-KO mouse
Abstract

Ehlers-Danlos syndrome (EDS) is a group of disorders caused by abnormalities that are identified in the extracellular matrix. Transforming growth factor-β1 (TGF-β1) plays a crucial role in formation of the extracellular matrix. It has been reported that the loss of function of zinc transporter ZRT/IRT-like protein 13 (ZIP13) causes the spondylocheiro dysplastic form of EDS (SCD-EDS: OMIM 612350), in which dysregulation of the TGF-β1 signaling pathway is observed, although the relationship between the dermis abnormalities and peripheral TGF-β1 level has been unclear. We investigated the characteristics of the dermis of the Zip13-knockout (KO) mouse, an animal model for SCD-EDS. Both the ratio of dermatan sulfate (DS) in glycosaminoglycan (GAG) components and the amount of collagen were decreased, and there were very few collagen fibrils with diameters of more than 150 nm in Zip13-KO mice dermis. We also found that the TGF-β1 level was significantly higher in Zip13-KO mice serum. These results suggest that collagen synthesis and collagen fibril fusion might be impaired in Zip13-KO mice and that the possible decrease of decorin level by reduction of the DS ratio probably caused an increase of free TGF-β1 in Zip13-KO mice. In conclusion, skin fragility due to defective ZIP13 protein may be attributable to impaired extracellular matrix synthesis accompanied by abnormal peripheral TGF-β homeostasis.

Published
2015

14. Effects of Collagen Casing-Containing Diets Fed to Sows during Late Pregnancy Lactation and Farrowing on the Birth Performance, Growth, Meat Product and Serum Components in Piglets

Author

YAMADA, Michi, primary, WATANABE, Yuki, additional, YOSHIDA, Hanako, additional, MITANI, Syunoa, additional, HARA, Takayuki, additional, TAGAMI, Takayoshi, additional, IWASAKI, Tomohito, additional, SUGANO, Mikio, additional, TAKEHANA, Kazushige, additional, SUGIYAMA, Shinji, additional, EBIHARA, Tetsuya, additional, KOYAMA, Yoh-ichi, additional, YAMADA, Koji, additional, and NAKATSUJI, Hiroki, additional

Published
2017
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17. Detection of endogenous and food-derived collagen dipeptide prolylhydroxyproline (Pro-Hyp) in allergic contact dermatitis-affected mouse ear.

Author

00202094, Kusubata, Masashi, Koyama, Yoh-Ichi, Tometsuka, Chisa, Shigemura, Yasutaka, Sato, Kenji, 00202094, Kusubata, Masashi, Koyama, Yoh-Ichi, Tometsuka, Chisa, Shigemura, Yasutaka, and Sato, Kenji

Abstract

Generation of collagen dipeptides and deposition of orally administered prolylhydroxyproline (Pro-Hyp) in local inflammatory sites were examined in mice with hapten (2, 4-dinitrofluorobenzene)-induced dermatitis in the ear. Pro-Hyp content in the hapten-treated ear was significantly higher in the chronic phase of contact dermatitis than the vehicle control. In contrast, hydroxyprolylglycine contents remained at lower levels in all cases compared to Pro-Hyp. Four hours after the ingestion of [(13)C5, (15)N]Pro and [(13)C5, (15)N]Pro-Hyp, labeled-Pro-Hyp and Pro, respectively, appeared only in the ear with dermatitis. Thus, Pro-Hyp is generated and degraded as part of the rapid synthesis and degradation of collagen in the ear with dermatitis. In addition to the endogenously generated Pro-Hyp, the orally administered Pro-Hyp was deposited in the ears.

Published
2015

18. Collagen‐derived peptides modulate CD4+ T‐cell differentiation and suppress allergic responses in mice.

Author

Nishikimi, Akihiko, Koyama, Yoh‐ichi, Ishihara, Sayaka, Kobayashi, Shusaku, Tometsuka, Chisa, Kusubata, Masashi, Kuwaba, Kumiko, Hayashida, Osamu, Hattori, Shunji, and Katagiri, Koko

Subjects
*COLLAGEN, *CD4 antigen, *T cell differentiation, *ALLERGIES, *LABORATORY mice
Abstract

Abstract: Introduction: Collagen peptides have been widely used as a food supplement. After ingestion of collagen peptides, oligopeptides containing hydroxyproline (Hyp), which are known to have some physiological activities, are detected in peripheral blood. However, the effects of collagen‐peptide administration on immune response are unclear. In the present study, we tested the effects of collagen‐peptide ingestion on allergic response and the effects of collagen‐derived oligopeptides on CD4+ T‐cell differentiation. Methods: BALB/c mice fed a collagen‐peptide diet were immunized with ovalbumin (OVA), and their serum IgE and IgG levels, active cutaneous anaphylaxis, and cytokine secretion by splenocytes were examined. Naive CD4+ T cells were stimulated with anti‐CD3 and anti‐CD28 in the presence of collagen‐derived oligopeptides, and the expression of IFN‐γ, IL‐4, and Foxp3 was analyzed. Results: In an active anaphylaxis model, oral administration of collagen peptides suppressed serum OVA‐specific immunoglobulin E (IgE) production and diminished anaphylaxis responses. In this model, the ingestion of collagen peptides skewed the pattern of cytokine production by splenocytes toward T‐helper (Th) type 1 and regulatory T (Treg) cells. In vitro T‐helper cell differentiation assays showed that Hyp‐containing oligopeptides promoted Th1 differentiation by upregulating IFN‐γ‐induced signal transducer and activator of transcription 1 (STAT1) signaling. These oligopeptides also promoted the development of Foxp3+ Treg cells in response to antigen stimulation in the presence of TGF‐β. Conclusions: Collagen‐peptide ingestion suppresses allergic responses by skewing the balance of CD4+ T cells toward Th1 and Treg cells and seems to be a promising agent for preventing allergies and inflammatory diseases. [ABSTRACT FROM AUTHOR]

Published
2018
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