JOURNAL ARTICLE
REVIEW

[alpha Klotho and inorganic phosphate metabolism]

Ken-ichi Miyamoto, Hiroko Segawa, Mikiko Ito, Sawako Tatsumi
Clinical Calcium 2007, 17 (5): 698-703
17470998
Recent studies have demonstrated that klotho protein plays a role in calcium/phosphate homeostasis. Urakawa et al demonstrated that the concerted action of klotho and fibroblast growth factor receptor 1 reconstitutes the fibroblast growth factor 23 (FGF23) receptor (Nature 444,770,2006). We investigated the correlation between hyperphosphatemia and Pi transport activity in klotho mutant mice (kl/kl mice). kl/kl mice displayed hyperphosphatemia, high plasma 1,25 (OH) (2)D(3) levels, increased activity of the renal and intestinal sodium-dependent P (i) cotransporters, and increased levels of the type II a, type II b, and type II c transporter proteins compared with wild-type mice. Interestingly, transcript levels of the type II a/type II c transporter mRNA abundance, but not transcripts levels of type II b transporter mRNA, were markedly decreased in kl/kl mice compared with wild-type mice. Furthermore, plasma FGF23 levels were 150-fold higher in kl/kl mice than in wild-type mice. Feeding of a low-P (i) diet induced the expression of klotho protein and decreased plasma FGF23 levels in kl/kl mice, whereas colchicine treatment experiments revealed evidence of abnormal membrane trafficking of the type IIa transporter in kl/kl mice. These results indicate that hyperphosphatemia in klotho mice is due to dysregulation of expression and trafficking of the renal type II a/ II c transporters rather than to intestinal P (i) uptake.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
17470998
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"