English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Context: The type I membrane protein Klotho was recently shown to mediate PTH secretion in parathyroid cells in response to low extracellular calcium. In contrast, Klotho inhibits PTH secretion indirectly through the action of fibroblast growth factor-23. Abnormal Klotho expression in parathyroid disorders remains to be elucidated. Objective: The aim of the study was to determine: 1) Klotho expression in parathyroid adenomas from patients with primary hyperparathyroidism (pHPT) compared to normal tissue; and 2) its relation to the serum calcium and PTH levels. Design: Surgically removed parathyroid glands (n = 40) and four normal parathyroid tissue specimens were analyzed for Klotho mRNA and protein levels by quantitative real-time PCR and immunohistochemistry. In vitro effects of calcium on Klotho mRNA expression were studied in bovine parathyroid cells. Results: Klotho mRNA levels were significantly decreased (n = 23) or undetectable (n = 17) in parathyroid adenomas compared to normal tissues (P &amp;lt; 0.001). Reduced Klotho protein expression was confirmed by immunohistochemistry. Klotho mRNA levels were inversely correlated to serum calcium (r = −0.97; P &amp;lt; 0.0001), and calcium dose-dependently decreased Klotho mRNA expression in normal parathyroid cells in vitro (P &amp;lt; 0.01). Serum calcium was the only significant marker of Klotho expression in multivariate analysis with calcium, phosphate, PTH, and adenoma weight as independent variables. Conclusions: Parathyroid Klotho expression is decreased or undetectable in pHPT. We provide evidence that 1) serum calcium is strongly associated with parathyroid Klotho expression in pHPT; and 2) abnormal PTH secretion in hypercalcemic pHPT subjects is mediated by Klotho-independent mechanisms.

Type I Membrane Klotho Expression Is Decreased and Inversely Correlated to Serum Calcium in Primary Hyperparathyroidism