Gender Difference of Soft Tissue Calcification Induced by Cholecalciferol in Mice

• Published in: The FASEB journal 2007-04, Vol.21 (5), p.A497-A497
• Main Authors: Kim, Kyoung soon, Kim, Jae Hoon, Choi, Je Yong, Park, Mae Ja, Lee, Won Jung
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.21.5.A497-a

Calcification is almost invariably associated with atherosclerotic plaque formation. High doses of vitamin D have been known to induce soft tissue calcification and be toxic. Circulating endogenous estrogen is proposed to protect against cardiovascular disease. We investigated the importance of ovarian function in the progression of soft tissue calcification induced by a toxic dose of vitamin D and also evaluated changes in expression of the bone related genes such as osteopontin (OPN), osteoprotegrin (OPG) and matrix Gla protein (MGP) in mice. Cholecalciferol (500,000 IU/kg BW, sc) was injected at t= 0, 24, 48 h to male and three female groups: sham and ovariectomized (OVX) mice treated with or without estradiol (E2, 60 ug slow‐release pellet). Histological examination at 4 days from the first injection of cholecalciferol showed a remarkable calcification of the kidney cortex and lungs in male and OVX female mice. In contrast, the sham‐operated female and E2‐treated OVX mice showed almost no calcification in the soft tissues examined. Gene expression levels of OPG and MGP increased in the calcified renal cortex of male and OVX‐female mice, but were not changed in the sham and E2‐treated OVX female mice. On the other hand, the OPN mRNA level was not changed in any of the experimental groups. These results indicate a gender difference in soft tissue calcification induced by cholecalciferol, and suggest E2 as an important protective regulator in mice.