Effect of parathyroidectomy on osteopontin and undercarboxylated osteocalcin in patients with primary hyperparathyroidism. (2nd January 2018)

• Record Type: Journal Article
• Authors: Maser, Raelene E.; Lenhard, M. James; Pohlig, Ryan T.; Balagopal, P. Babu; Abdel-Misih, Raafat
• Is Part Of: Endocrine research. Volume 43:Number 1(2018)
• Page Start: 21
• Page End: 28
• Publication Date: 2018-01-02
• Subjects: Osteopontin -- parathyroidectomy -- primary hyperparathyroidism -- undercarboxylated osteocalcin; Endocrinology, Experimental -- Periodicals; Endocrinology -- Periodicals; Endocrinology -- Periodicals; Research -- Periodicals; 616.4
• DOI: 10.1080/07435800.2017.1369432
• Languages: English
• ISSNs: 0743-5800

Abstract

ABSTRACT: Purpose : Surgical treatment for primary hyperparathyroidism (PHPT) improves bone metabolism. Osteocalcin (OC) and its undercarboxylated form (ucOC) are associated with bone and energy metabolism. Osteopontin (OPN), a multifunctional protein expressed in bone, is involved in resorption, along with β-carboxyl-terminal cross-linking telopeptide of type 1 collagen (β-CTX), and osteoprotegerin (OPG). Our aim was to investigate these biomarkers of bone metabolism in patients with PHPT.Methods : We examined 30 individuals with PHPT, in a clinical research facility, before and 1 month following parathyroidectomy. Circulating levels of OC, ucOC, OPN, β-CTX, and OPG were examined as bone biomarkers along with inflammatory markers (e.g., interleukin-6 [IL-6], lipocalin-2), insulin resistance (i.e., homeostasis model assessment for insulin resistance [HOMA-IR]), adiposity (i.e., leptin, adiponectin), PTH, calcium, 25-hydroxyvitamin D, creatinine, and demographics.Results : Participants (27 females/3 males) were 60 ± 9 (mean±SD) years old. There was a significant reduction of ucOC (7.9 ± 5.1 [median±SIQR] vs. 6.6 ± 3.7 ng/mL, p = 0.022) and OPN (75.4 ± 14.5 vs. 54.5 ± 9.2 ng/mL, p < 0.001) pre- versus post-parathyroidectomy. There were no univariate differences postoperatively for IL-6, HOMA-IR, leptin, or adiponectin. Regression analysis showed that postoperative levels of adiponectin, IL-6, and OPN were significantly associated with ucOC, while adjusting for PTH and albumin corrected calcium levels (model R 2 = 0.610, p = 0.001). With OPN as the dependent variable, higher adiponectin and lower ucOC were significantly associated with lower OPN levels postoperatively (model R 2 = 0.505, p = 0.010).Conclusion : The lower 1-month postoperative OPN and ucOC levels in PHPT seem to indicate reduced bone resorption. Decreased ucOC levels may also suggest lower energy demands postoperatively.