Parathyroid‐specific deletion of dicer‐dependent microRNAs abrogates the response of the parathyroid to acute and chronic hypocalcemia and uremia. Issue 9 (8th June 2015)

• Record Type: Journal Article
• Authors: Shilo, Vitali; Ben‐Dov, Iddo Z.; Nechama, Morris; Silver, Justin; Naveh‐Many, Tally
• Is Part Of: FASEB journal. Volume 29:Issue 9(2015)
• Page Start: 3964
• Page End: 3976
• Publication Date: 2015-06-08
• Subjects: secondary hyperparathyroidism -- calcium‐sensing receptor -- renal failure; Biology -- Periodicals; Biology, Experimental -- Periodicals; 570
• DOI: 10.1096/fj.15-274191
• Languages: English
• ISSNs: 0892-6638

Abstract

ABSTRACT: MicroRNAs (miRNAs) down‐regulate gene expression and have vital roles in biology but their functions in the parathyroid are unexplored. To study this, we generated parathyroid‐specific Dicer1 knockout (PT‐ Dicer ‐/‐ ) mice where parathyroid miRNA maturation is blocked. Remarkably, the PT‐ Dicer ‐/‐ mice did not increase serum parathyroid hormone (PTH) in response to acute hypocalcemia compared with the >5‐f old increase in controls. PT‐ Dicer ‐/‐ glands cultured in low‐calcium medium secreted 5‐fold less PTH at 1.5 h than controls. Chronic hypocalcemia increased serum PTH >4‐f old less in PT‐ Dicer ‐/‐ mice compared with control mice with no increase in PTH mRNA levels and parathyroid cell proliferation compared with the 2‐ to 3‐fold increase in hypocalcemic controls. Moreover, uremic PT‐ Dicer ‐/‐ mice increased serum PTH and FGF23 significantly less than uremic controls. Therefore, stimulation of the parathyroid by both hypocalcemia and uremia is dependent upon intact dicer function and miRNAs. In contrast, the PT‐ Dicer ‐/‐ mice responded normally to activation of the parathyroid calcium‐sensing receptor (Casr) by both hypercalcemia and a calcimimetic that decreases PTH secretion, demonstrating that they are dicer‐independent Therefore, miRNAs are essential for the response of the parathyroid to both acute and chronic hypocalcemia and uremia, the major stimuli for PTH secretion.—Shilo, V., Ben‐Dov, I. Z., Nechama, M., Silver, J., Naveh‐Many, T. Parathyroid‐specific deletion of dicer‐dependent microRNAs abrogates the response of the parathyroid to acute and chronic hypocalcemia and uremia. FASEB J. 29, 3964‐3976 (2015). www.fasebj.org