Generation of novel genetically modified rats to reveal the molecular mechanisms of vitamin D actions

Miyu Nishikawa; Kaori Yasuda; Masashi Takamatsu; Keisuke Abe; Kairi Okamoto; Kyohei Horibe; Hiroki Mano; Kimie Nakagawa; Naoko Tsugawa; Yoshihisa Hirota; Tetsuhiro Horie; Eiichi Hinoi; Toshio Okano; Shinichi Ikushiro; Toshiyuki Sakaki

doi:10.1038/s41598-020-62048-1

Generation of novel genetically modified rats to reveal the molecular mechanisms of vitamin D actions

Sci Rep. 2020 Mar 30;10(1):5677. doi: 10.1038/s41598-020-62048-1.

Authors

Affiliations

¹ Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan.
² Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan.
³ Department of Hygienic Sciences, Kobe Pharmaceutical University, 4-19-1 Motoyamakita-machi, Higashinada-ku, Kobe, 658-8558, Japan.
⁴ Department of Health and Nutrition, Faculty of Health and Nutrition, Osaka Shoin Women's University, 4-2-26 Hishiya-nishi, Higashi-Osaka, 577-8550, Japan.
⁵ Laboratory of Biochemistry, Faculty of Bioscience and Engineering, College of Systems Engineering and Science, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama, 337-8570, Japan.
⁶ Laboratory of Pharmacology, Department of Bioactive Molecules, Gifu Pharmaceutical University, Gifu, Japan.
⁷ United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, Gifu, Japan.
⁸ Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama, 939-0398, Japan. tsakaki@pu-toyama.ac.jp.

Abstract

Recent studies have suggested that vitamin D activities involve vitamin D receptor (VDR)-dependent and VDR-independent effects of 1α,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) and 25-hydroxyvitamin D₃ (25(OH)D₃) and ligand-independent effects of the VDR. Here, we describe a novel in vivo system using genetically modified rats deficient in the Cyp27b1 or Vdr genes. Type II rickets model rats with a mutant Vdr (R270L), which recognizes 1,25(OH)₂D₃ with an affinity equivalent to that for 25(OH)D₃, were also generated. Although Cyp27b1-knockout (KO), Vdr-KO, and Vdr (R270L) rats each showed rickets symptoms, including abnormal bone formation, they were significantly different from each other. Administration of 25(OH)D₃ reversed rickets symptoms in Cyp27b1-KO and Vdr (R270L) rats. Interestingly, 1,25(OH)₂D₃ was synthesized in Cyp27b1-KO rats, probably by Cyp27a1. In contrast, the effects of 25(OH)D₃ on Vdr (R270L) rats strongly suggested a direct action of 25(OH)D₃ via VDR-genomic pathways. These results convincingly suggest the usefulness of our in vivo system.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

25-Hydroxyvitamin D3 1-alpha-Hydroxylase / genetics
Animals
Calcifediol / genetics
Calcifediol / metabolism
Calcitriol / pharmacology
Disease Models, Animal
Male
Rats
Rats, Wistar
Receptors, Calcitriol / genetics*
Receptors, Calcitriol / metabolism*
Rickets / metabolism
Vitamin D / analogs & derivatives
Vitamin D / genetics
Vitamin D / metabolism*
Vitamin D3 24-Hydroxylase / genetics

Substances

Receptors, Calcitriol
dihydroxy-vitamin D3
Vitamin D
1,25-dihydroxyvitamin D
Vitamin D3 24-Hydroxylase
25-Hydroxyvitamin D3 1-alpha-Hydroxylase
Calcitriol
Calcifediol