Skip to main content
Download PDF

Interaction between serum FGF-23 and PTH in renal phosphate excretion, a case-control study in hypoparathyroid patients

BMC Nephrology volume 21, Article number: 176 (2020) Cite this article

Abstract

Background

phosphate homeostasis is mediated through complex counter regulatory feed-back balance between parathyroid hormone, FGF-23 and 1,25(OH)2D. Both parathyroid hormone and FGF-23 regulate proximal tubular phosphate excretion through signaling on sodium- phosphate cotransporters IIa and IIc. However, the interaction between these hormones on phosphate excretion is not clearly understood. We performed the present study to evaluate whether the existence of sufficient parathyroid hormone is necessary for full phosphaturic function of FGF-23 or not.

Methods

In this case-control study, 19 patients with hypoparathyroidism and their age- and gender-matched normal population were enrolled. Serum calcium, phosphate, alkaline phosphatase,parathyroid hormone, FGF-23, 25(OH)D, 1,25(OH)2D and Fractional excretion of phosphorous were assessed and compared between the two groups, using SPSS software.

Results

The mean serum calcium and parathyroid hormone level was significantly lower in hypoparathyroid patients in comparison with the control group (P < 0.001 and P < 0.001, respectively). We found high serum level of phosphate and FGF-23 in hypoparathyroid patients compared to the control group (P < 0.001 and P < 0.001, respectively). However, there was no significant difference in Fractional excretion of phosphorous or 1,25OH2D level between the two groups. There was a positive correlation between serum FGF-23 and Fractional excretion of phosphorous just in the normal individuals (P < 0.001, r = 0.79).

Conclusions

Although the FGF-23 is a main regulator of urinary phosphate excretion but the existence of sufficient parathyroid hormone is necessary for the full phosphaturic effect of FGF-23.

Peer Review reports

Background

Phosphorus (PO4) has several biologic role in human, and is an essential ion in bone mineral component, cell membrane structure, and energy exchange. Also, it is a second messenger in controlling cellular biochemical activities through phosphorylation or dephosphorylation [1,2,3]. Kidney plays an important role in PO4 homeostasis. About 80% of the filtered PO4 is reabsorbed through specific sodium- phosphate cotransporters (NaPi IIa and IIc) located in the proximal tubule [4,5,6,7,8].

PO4 serum concentration is kept within the normal range by a complex regulation between intestinal absorption, renal filtration- reabsorption, and bone resorption of PO4 mediated by regulatory hormones [9,10,11]. The most important hormones that regulate tubular PO4 handling, are parathyroid hormone (PTH) secreted by the parathyroid gland, and fibroblast growth factor 23 (FGF-23), which is an osteocytes derived hormone. FGF-23 decreases serum PO4 by inhibiting renal PO4 reabsorption through FGF-23-Klotho (coreceptor) signaling on NaPi IIa and IIc at proximal tubule of the kidney. FGF-23 also suppresses 1,25-dihydroxyvitamin D (1,25(OH)2 D) production by decreasing 1α-hydroxylase expression [12,13,14]. PTH promotes PO4 excretion by suppressing NaPi-II in the kidney [15]. PTH also enhances calcium absorption through the direct effect on bones and kidneys, and indirectly increases intestinal calcium and PO4 absorption via the stimulation of 1α -hydroxylase activity and increase 1,25(OH)2 D production [16,17,18]. The same site of action of FGF-23 and PTH in NaPi IIa and IIc at proximal tubule of kidney might raise the question that whether there is an overlapping effect between these hormones or not?

Hypoparathyroidism is a rare endocrine disorder characterized by inappropriately low or absent levels of PTH associated with hypocalcemia and hyperphosphatemia [17, 19]. Hypoparathyroidism might occur as a primary congenital defect or might be due to a secondary cause. The most common cause of secondary hypoparathyroidism is the incidental destruction of parathyroid glands during anterior neck surgeries. Other causes are autoimmune disorders, radiation to the neck and infiltrative disorders of the parathyroid glands [20,21,22].

In the present study, we aim to evaluate the role of FGF-23 on PO4 hemostasis in state of low or insufficient PTH in human. Hence, we conducted this case – control study to evaluate whether the renal excretion of PO4 by serum FGF-23 in patients with hypoparathyroidism was different from normal population or not.

Methods

Patients and method

A total of 38 participants including 19 patients with hypoparathyroidism and their healthy controls were enrolled in this study. The study was performed at Shiraz University of Medical Sciences affiliated endocrine clinics in Fars province, southern Iran, from October 2017 till March 2018. Both groups were matched for age and gender. Hypoparathyroidism was diagnosed on the basis of hypocalcemia (serum calcium less than 8.5 mg/dl) accompanied with documented PTH levels below the lower limit of the normal range.

All hypoparathyroid patients were follow up by an expert endocrinologist. Patients received proper doses of calcium carbonate (500 mg tablet, manufactured Toliddaru pharmaceutical, Tehran, Iran), and calcitriol (0.25 μg capsule, manufactured Zahravi pharmaceutical, Tehran, Iran) to maintain albumin-corrected serum calcium in the low-normal range (8–9 mg/dl) [23]. The exclusion criteria in both groups were renal failure (Glomerular filtration rate less than 60 ml/min), liver failure, other metabolic bone disease (e.g., rickets), hyperthyroidism, and diabetes mellitus. None of the patients received phosphate binder resins during the study.

Laboratory tests

All the samples were taken after 8 h overnight fasting. Blood samples were centrifuged for 15 min at 3000 rpm and the plasma was collected and stored at − 70 °C till further analysis. All the biochemical studies were performed at the endocrinology and metabolism research center laboratory of Shiraz University of Medical Sciences. Colorimetric assays were used to measure calcium (mg/dL), phosphorus (mg/dL), albumin (g/dL) and alkaline phosphatase (ALP) (IU/L) levels, by using Biosystem SA auto-analyzer, made in Spain. Serum PTH (pg/ml) and 25(OH)D (ng/ml) levels were assessed by Electrochemiluminescence methods produced by Roche company in Germany with Sensitivity, intra- and inter-assay CVs 3.3 and 5.1%, respectively. ELISA method was used to determine the serum intact FGF-23 (pg/ ml) and 1,25(OH)2D (pmol/l) using Bioassay technology laboratory kit. Intra- and inter-assay CVs for 1,25(OH)2D and FGF-23 were < 8 and < 10%, respectively. Normal references for serum calcium, phosphorus, ALP, PTH, 25(OH)D and 1,25(OH)2D were 8.5–10.5 mg/ dL, 3.5–5.5 mg/ dL, 44–147 IU/L, 10–65(pg/ml), 20–100 ng/ml, and 20 to 45 pg/ml, respectively. Initial morning urine collection was done to determine renal PO4 clearance. Urinary PO4 and creatinine concentrations were determined by digital flame spectrophotometer. Fractional excretion of phosphorous (FE PO4) was done using the following formula: FE PO4 = [PO4 (Urine) × Creatinine (Serum)] / [PO4 (Serum) × Creatinine (Urine)] × 100.

Ethical statement

An informed written consent form was obtained from the participants after explaining the aim, method and goal of the study. Shiraz University of Medical Sciences local Ethics Committee and Vice-Chancellor of research at SUMS approved this study with number 1396-01-01-15,805.

Statistics

SPSS statistical software (version 22, IBM) were used to perform Statistical analysis. Data are mentioned as mean ± SD. Shapiro-Wilk was used to evaluate the normality of data distribution. Normally distributed data were compared using Student’s t-test, and the Mann–Whitney test was used to compare non-normally distributed ones. Pearson’s test and Spearman’s ranking test were used to evaluate the correlations between normally distributed parameters and non-normal distributed ones, respectively. P value less than 0.05 was considered to be statically significant.

Results

A total of 38 participants were enrolled in this study, 19 with hypoparathyroidism as case group and 19 volunteers with normal parathyroid function as the control group. Mean age in the case and control groups was 43.6 ± 17 years and 46.7 ± 15.9 years, which was not statistically significant (P = 0.57). Both case and control groups included 5 male and 14 female. Also, there were no significant differences in weight and BMI between case and control groups.

In the case group, 9 patients had hypoparathyroidism due to previous neck thyroidectomy and 10 patients were case of primary hypoparathyroidism. General characteristic of patients and controls are summarized in Table 1.

Table 1 General characteristics and biochemical studies in both case and control groups and the related comparisons
Full size table

The mean serum calcium and PTH level was significantly lower in the case group in comparison with the control group (P < 0.001 and P < 0.001, respectively). In patients with hypoparathyroidism serum PO4 was significantly higher than the control group (P < 0.001). Serum FGF-23 was higher in patients with hypoparathyroidism in comparison with the control group (P = 0.001). However, there was no significant difference between the case and control groups with respect to the mean serum level of 1,25(OH)2D, 25(OH)D, ALP, and FE PO4 (P = 0.25, P = 0.11, P = 0.23 and P = 0.08, respectively).

As shown in Table 2 there was a strong positive correlation between FGF-23 and FE PO4 in the control; however, this correlation was not observed amongst hypoparathyroid patients. There was no correlation between FE PO4, serum PO4, PTH and 1, 25(OH)2 D in both case and control groups. Figure 1 shows the correlation between values of FE PO4 and serum FGF-23 in both control and case groups (Spearman rho =0.79, P < 0.001). In addition, we have done an analysis in our hypoparathyroid patients evaluating the association of FGF23 and serum calcium in 2 separate group of low calcium and normal calcium level. It showed that there was no correlation between calcium and FGF23 in low calcium and normal calcium level groups (P = 0.598 and P = 0.054, respectively).

Table 2 Correlation between fractional excretion of PO4 and serum biochemical parameters in the case and control groups, separately
Full size table
Fig. 1
figure 1

The correlation between values of serum FE PO4 and FGF-23 in control group (a) and hypoparathyroid cases (b)

Full size image

Discussion

Maintaining serum PO4 homeostasis necessitates a complex counter regulatory feed-back balance between PTH, FGF-23 and 1,25(OH)2 D [24,25,26]. FGF-23 and PTH are probably the most important phosphaturic hormones in human [1]. FGF-23 is mainly produced by osteoblasts and osteocytes. Local expression of FGF-23 coreceptor (Klotho) is necessary for its function at the renal proximal tubules [27]. It inhibits renal Phos reabsorption through inhibitory effects on NaPi IIa and II c at proximal renal tubules [28]. However, there are still controversies about the action site of FGF-23 in the kidney [29]. previous studies had showed that klotho is essentially expressed in distal renal tubules, and alteration in the extracellular signal-regulated kinase (ERK) phosphorylation in distal tubules occurs soon after FGF-23 injection [30, 31]. Therefore, it still remain unclear as how FGF-23 could affect proximal tubules to suppress phosphate reabsorption. Data suggest that FGF-23 might require other factors such as PTH for signal transduction pathway at the proximal tubules [32].

PTH also increases renal PO4 excretion at proximal tubule of the kidney by reducing apical membrane NaPi IIa and IIc [14, 33, 34]. Moreover, PTH increases FGF-23 gene expression [35]. In addition to kidneys, parathyroid gland also express considerable amount of klotho and FGF-23 receptor [36]. On the other hand, FGF-Klotho complex could activate the MAPK pathway leading to decreased PTH mRNA and PTH secretion [37,38,39]. Olena et al. showed that the phosphaturic actions of PTH, are blunted by FGF-23 or Klotho deficiency. Hence, FGF-23 might be an important modulator of PTH signaling in the kidney [40].

Although the regulatory counterbalance between FGF-23 and PTH secretion was investigated, there is still insufficient information about the role of PTH on phosphaturic function of FGF-23 in human. Study of phosphaturic effect of FGF-23 in normal human physiology might be confounded by the fact that PTH and FGF-23 have some overlapping effects on PO4 excretion. Hence, the present study on hypoparathyroid patients and normal population provides an opportunity to observe whether the phosphaturic effect of FGF-23 is independent of PTH or not.

In the present study, we detected high serum level of PO4 and FGF-23 in hypoparathyroid patients compared to the control group; however, we found no significant difference in FE PO4 or 1,25(OH)2 D level between the two groups. Also, we found a strong positive correlation between serum FGF-23 and FE PO4 in the control population, but this correlation was absent in hypoparathyroid patients. These findings could suggest that although the FGF-23 is one of the main regulator of urinary PO4 excretion, the existence of intact PTH is necessary for the full phosphaturic effect of FGF-23. However, further relevant human studies are warranted.

In the presence of normal parathyroid and kidney function inappropriate high serum FGF-23 could result in urinary PO4 loss and hypophosphatemia such as X-linked dominant hypophosphatemic rickets (XLH), [41,42,43,44], autosomal dominant hypophosphatemic rickets [45, 46], Autosomal recessive hypophosphatemic rickets (ARHR) [47, 48] or Fibrous dysplasia (FD)/McCune–Albright syndrome [49]. As well as some acquired disorders such as Tumor-induced osteomalacia (TIO) [50,51,52].

Previous studies showed that mean serum PO4 levels in hypoparathyroid patients remained above the normal range, even in the presence of high serum FGF-23 level [53].Yamashita et al. showed that in transient hypoparathyroidism high serum level of FGF23 and hyperphosphatemia will be normalized only after parathyroid recovery [54]. Animal studies also showed that PTH-null mice experienced high PO4 in spite of high circulating FGF-23, resembling participants with hypoparathyroidism in the present study [55]. In another study on hypoparathyroid patients, treatment with rhPTH could reduce serum PO4 level from the upper normal range to the normal values parallel with increased urinary PO4 excretion [56,57,58]. These findings also support our hypothesis about the importance of PTH in phosphaturic action of FGF-23. Another explanation by Gracia-Iguacel et al. was that PTH may have effect on phosphaturic function of FGF-23 through the serum calcium level [59]. Also, some studies showed that FGF23 have positive correlation with serum calcium [60, 61]. In our study, we found no correlation between calcium and FGF23 in low calcium and normal calcium level hypoparathyroid patients. However, the number of hypoparathyroid patients in low Ca group was just 7, which could affect the results. Another important issue in this regards was that normal renal function is necessary for this association. In some patients with chronic kidney disease, high serum phosphate was observed in spite of high serum PTH and FGF23 level [62]. Also, it was shown that in chronic kidney disease patients treated with hemodialysis, FGF23 could predict the progression of secondary hyperparathyroidism. Interestingly, in these patients total parathyroidectomy could decrease high serum FGF-23 level to normal values [63, 64].

In spite of many strengths of this study that evaluated FGF23 function in hypoparathyroid patients, we had some limitations. This study was a case-control cross sectional study, which could be better if we design an interventional clinical trial to evaluate the effect of PTH in hypoparathyroid patients in the future.

Conclusion

The present study could suggest that although the FGF-23 is one of the main regulator of urinary PO4 excretion, the existence of sufficient parathyroid hormone is necessary for the full phosphaturic effect of FGF-23. We hypothesized that PTH might play a role in PO4 excretory signal pathway of FGF-23. However, further in vivo and in vitro studies are necessary to determine the mechanism of action of parathyroid hormone on PO4 excretory function of FGF-23.

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Abbreviations

1,25(OH)2 D:

1,25-dihydroxyvitamin D

25OHD:

25-hydroxy vitamin D

ALP:

Alkaline phosphatase

Ca:

Calcium

CKD:

Chronic kidney diseases

DXA:

Dual-energy X-ray absorptiometry

FE PO:

Fractional excretion of phosphorous

FGF-23:

Fibroblast growth factor 23

PTH:

Parathyroid hormone

PO4 :

Phosphorus

SUMS:

Shiraz University of Medical Sciences

NaPi IIa and IIc :

Sodium- phosphate cotransporters

References

  1. Jüppner H. Phosphate and FGF-23. Kidney Int. 2011;79:S24–S7.

    Article  CAS  Google Scholar 

  2. Miyamoto K-I, Haito-Sugino S, Kuwahara S, Ohi A, Nomura K, Ito M, et al. Sodium-dependent phosphate cotransporters: lessons from gene knockout and mutation studies. J Pharm Sci. 2011;100(9):3719–30.

    Article  CAS  PubMed  Google Scholar 

  3. Berndt T, Kumar R. Novel mechanisms in the regulation of phosphorus homeostasis. Physiology. 2009;24(1):17–25.

    Article  CAS  PubMed  Google Scholar 

  4. Kuro-o M. Endocrine FGFs and Klothos: emerging concepts. Trends Endocrinol Metabolism. 2008;19(7):239–45.

    Article  CAS  Google Scholar 

  5. Berndt TJ, Schiavi S, Kumar R. “Phosphatonins” and the regulation of phosphorus homeostasis. Am J Physiol-Renal Physiol. 2005;289(6):F1170–F82.

    Article  CAS  PubMed  Google Scholar 

  6. Murer H, Hernando N, Forster I. Biber Jr. proximal tubular phosphate reabsorption: molecular mechanisms. Physiol Rev. 2000;80(4):1373–409.

    Article  CAS  PubMed  Google Scholar 

  7. Tenenhouse HS, Murer H. Disorders of renal tubular phosphate transport. J Am Soc Nephrol. 2003;14(1):240–7.

    Article  PubMed  Google Scholar 

  8. Fujii T, Shiozaki Y, Segawa H, Nishiguchi S, Hanazaki A, Noguchi M, et al. Analysis of opossum kidney NaPi-IIc sodium-dependent phosphate transporter to understand pi handling in human kidney. Clin Exp Nephrol. 2019;23(3):313–24.

    Article  CAS  PubMed  Google Scholar 

  9. Farrow EG, White KE. Recent advances in renal phosphate handling. Nat Rev Nephrol. 2010;6(4):207.

    Article  PubMed  PubMed Central  Google Scholar 

  10. Marks J, Debnam ES, Unwin RJ. Phosphate homeostasis and the renal-gastrointestinal axis. Am J Physiol-Renal Physiol. 2010;299(2):F285–F96.

    Article  CAS  PubMed  Google Scholar 

  11. Kaneko I, Tatsumi S, Segawa H. Miyamoto K-i. control of phosphate balance by the kidney and intestine. Clin Exp Nephrol. 2017;21(1):21–6.

    Article  CAS  PubMed  Google Scholar 

  12. Shimada T, Hasegawa H, Yamazaki Y, Muto T, Hino R, Takeuchi Y, et al. FGF-23 is a potent regulator of vitamin D metabolism and phosphate homeostasis. J Bone Miner Res. 2004;19(3):429–35.

    Article  CAS  PubMed  Google Scholar 

  13. Shimada T, Kakitani M, Yamazaki Y, Hasegawa H, Takeuchi Y, Fujita T, et al. Targeted ablation of Fgf23 demonstrates an essential physiological role of FGF23 in phosphate and vitamin D metabolism. J Clin Invest. 2004;113(4):561–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Fujii T, Segawa H, Hanazaki A, Nishiguchi S, Minoshima S, Ohi A et al. Role of the putative PKC phosphorylation sites of the type IIc sodium-dependent phosphate transporter in parathyroid hormone regulation. Clin Exp Nephrol. 2019;23:898–907.

  15. Weinman EJ, Biswas RS, Peng Q, Shen L, Turner CL, Xiaofei E, et al. Parathyroid hormone inhibits renal phosphate transport by phosphorylation of serine 77 of sodium-hydrogen exchanger regulatory factor–1. J Clin Invest. 2007;117(11):3412–20.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Shoback D. Hypoparathyroidism. N Engl J Med. 2008;359(4):391–403.

    Article  CAS  PubMed  Google Scholar 

  17. Bilezikian JP, Khan A, Potts JT, Brandi ML, Clarke BL, Shoback D, et al. Hypoparathyroidism in the adult: epidemiology, diagnosis, pathophysiology, target-organ involvement, treatment, and challenges for future research. J Bone Miner Res. 2011;26(10):2317–37.

    Article  CAS  PubMed  Google Scholar 

  18. Pajevic PD, Wein MN, Kronenberg HM. Parathyroid hormone actions on bone and kidney. Hypoparathyroidism. Milano: Springer; 2015. p. 99–109.

  19. Hadker N, Egan J, Sanders J, Lagast H, Clarke B. Understanding the burden of illness associated with hypoparathyroidism reported among patients in the paradox study. Endocr Pract. 2014;20(7):671–9.

    Article  PubMed  Google Scholar 

  20. Marx SJ. Hyperparathyroid and hypoparathyroid disorders. N Engl J Med. 2000;343(25):1863–75.

    Article  CAS  PubMed  Google Scholar 

  21. Underbjerg L, Sikjaer T, Mosekilde L, Rejnmark L. Cardiovascular and renal complications to postsurgical hypoparathyroidism: a Danish nationwide controlled historic follow-up study. J Bone Miner Res. 2013;28(11):2277–85.

    Article  PubMed  Google Scholar 

  22. Powers J, Joy K, Ruscio A, Lagast H. Prevalence and incidence of hypoparathyroidism in the United States using a large claims database. J Bone Miner Res. 2013;28(12):2570–6.

    Article  PubMed  Google Scholar 

  23. Abate EG, Clarke BL. Review of hypoparathyroidism. Front Endocrinol. 2017;7:172.

    Article  Google Scholar 

  24. Berndt T, Kumar R. Phosphatonins and the regulation of phosphate homeostasis. Annu Rev Physiol. 2007;69:341–59.

    Article  CAS  PubMed  Google Scholar 

  25. Imel EA, Econs MJ. Fibroblast growth factor 23: roles in health and disease. J Am Soc Nephrol. 2005;16(9):2565–75.

    Article  CAS  PubMed  Google Scholar 

  26. Quarles LD. Endocrine functions of bone in mineral metabolism regulation. J Clin Invest. 2008;118(12):3820–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Tan SJ, Smith ER, Hewitson TD, Holt SG, Toussaint ND. The importance of klotho in phosphate metabolism and kidney disease. Nephrology. 2014;19(8):439–49.

    Article  CAS  PubMed  Google Scholar 

  28. Strom TM, Jüppner H. Phex, FGF23, DMP1 and beyond. Curr Opin Nephrol Hypertens. 2008;17(4):357–62.

    Article  CAS  PubMed  Google Scholar 

  29. Andrukhova O, Zeitz U, Goetz R, Mohammadi M, Lanske B, Erben RG. FGF23 acts directly on renal proximal tubules to induce phosphaturia through activation of the ERK1/2–SGK1 signaling pathway. Bone. 2012;51(3):621–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Farrow EG, Davis SI, Summers LJ, White KE. Initial FGF23-mediated signaling occurs in the distal convoluted tubule. J Am Soc Nephrol. 2009;20(5):955–60.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Kuro-o M. The FGF23 and Klotho system beyond mineral metabolism. Clin Exp Nephrol. 2017;21(1):64–9.

    Article  CAS  PubMed  Google Scholar 

  32. Chang Q, Hoefs S, Van Der Kemp A, Topala C, Bindels R, Hoenderop J. The ß-glucuronidase klotho hydrolyzes and activates the TRPV5 channel. Science. 2005;310(5747):490–3.

    Article  CAS  PubMed  Google Scholar 

  33. Cole JA. Parathyroid hormone activates mitogen-activated protein kinase in opossum kidney cells. Endocrinology. 1999;140(12):5771–9.

    Article  CAS  PubMed  Google Scholar 

  34. de Groot T, Lee K, Langeslag M, Xi Q, Jalink K, Bindels RJ, et al. Parathyroid hormone activates TRPV5 via PKA-dependent phosphorylation. J Am Soc Nephrol. 2009;20(8):1693–704.

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  35. Lavi-Moshayoff V, Wasserman G, Meir T, Silver J, Naveh-Many T. PTH increases FGF23 gene expression and mediates the high-FGF23 levels of experimental kidney failure: a bone parathyroid feedback loop. Am J Physiol-Renal Physiol. 2010;299(4):F882–F9.

    Article  CAS  PubMed  Google Scholar 

  36. Imura A, Tsuji Y, Murata M, Maeda R, Kubota K, Iwano A, et al. α-Klotho as a regulator of calcium homeostasis. Science. 2007;316(5831):1615–8.

    Article  CAS  PubMed  Google Scholar 

  37. Ben-Dov IZ, Galitzer H, Lavi-Moshayoff V, Goetz R, Kuro-o M, Mohammadi M, et al. The parathyroid is a target organ for FGF23 in rats. J Clin Invest. 2007;117(12):4003–8.

    CAS  PubMed  PubMed Central  Google Scholar 

  38. Krajisnik T, Björklund P, Marsell R, Ljunggren O, Akerström G, Jonsson KB, et al. Fibroblast growth factor-23 regulates parathyroid hormone and 1-hydroxylase expression in cultured bovine parathyroid cells. J Endocrinol. 2007;195(1):125–31.

    Article  CAS  PubMed  Google Scholar 

  39. Canalejo R, Canalejo A, Martinez-Moreno JM, Rodriguez-Ortiz ME, Estepa JC, Mendoza FJ, et al. FGF23 fails to inhibit uremic parathyroid glands. J Am Soc Nephrol. 2010;21(7):1125–35.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Andrukhova O, Streicher C, Zeitz U, Erben RG. Fgf23 and parathyroid hormone signaling interact in kidney and bone. Mol Cell Endocrinol. 2016;436:224–39.

    Article  CAS  PubMed  Google Scholar 

  41. Jonsson KB, Zahradnik R, Larsson T, White KE, Sugimoto T, Imanishi Y, et al. Fibroblast growth factor 23 in oncogenic osteomalacia and X-linked hypophosphatemia. N Engl J Med. 2003;348(17):1656–63.

    Article  CAS  PubMed  Google Scholar 

  42. Yamazaki Y, Okazaki R, Shibata M, Hasegawa Y, Satoh K, Tajima T, et al. Increased circulatory level of biologically active full-length FGF-23 in patients with hypophosphatemic rickets/osteomalacia. J Clin Endocrinol Metabolism. 2002;87(11):4957–60.

    Article  CAS  Google Scholar 

  43. Miyamoto K-I, Taketani Y, Morita K, Segawa H, Nii T, Fujioka A, et al. Molecular and cellular regulation of renal phosphate transporters in X-linked hypophosphatemia. Clin Exp Nephrol. 1998;2(3):178–82.

    Article  CAS  Google Scholar 

  44. Nii T, Taketani Y, Tani Y, Ohkido I, Segawa H, Yamamoto H, et al. Direct demonstration of humorally mediated inhibition of the transcription of phosphate transporter in XLH patients. Clin Exp Nephrol. 2001;5(3):144–52.

    Article  CAS  Google Scholar 

  45. Shimada T, Muto T, Urakawa I, Yoneya T, Yamazaki Y, Okawa K, et al. Mutant FGF-23 responsible for autosomal dominant hypophosphatemic rickets is resistant to proteolytic cleavage and causes hypophosphatemia in vivo. Endocrinology. 2002;143(8):3179–82.

    Article  CAS  PubMed  Google Scholar 

  46. Imel EA, Hui SL, Ecibs MJ. FGF23 concentrations vary with disease status in autosomal dominant hypophosphatemic rickets. J Bone Miner Res. 2007;22(4):520–6.

    Article  CAS  PubMed  Google Scholar 

  47. Levy-Litan V, Hershkovitz E, Avizov L, Leventhal N, Bercovich D, Chalifa-Caspi V, et al. Autosomal-recessive hypophosphatemic rickets is associated with an inactivation mutation in the ENPP1 gene. Am J Hum Genet. 2010;86(2):273–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Lorenz-Depiereux B, Schnabel D, Tiosano D, Häusler G, Strom TM. Loss-of-function ENPP1 mutations cause both generalized arterial calcification of infancy and autosomal-recessive hypophosphatemic rickets. Am J Hum Genet. 2010;86(2):267–72.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Riminucci M, Collins MT, Fedarko NS, Cherman N, Corsi A, White KE, et al. FGF-23 in fibrous dysplasia of bone and its relationship to renal phosphate wasting. J Clin Invest. 2003;112(5):683–92.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  50. Shimada T, Mizutani S, Muto T, Yoneya T, Hino R, Takeda S, et al. Cloning and characterization of FGF23 as a causative factor of tumor-induced osteomalacia. Proc Natl Acad Sci. 2001;98(11):6500–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  51. Folpe AL, Fanburg-Smith JC, Billings SD, Bisceglia M, Bertoni F, Cho JY, et al. Most osteomalacia-associated mesenchymal tumors are a single histopathologic entity: an analysis of 32 cases and a comprehensive review of the literature. Am J Surg Pathol. 2004;28(1):1–30.

    Article  PubMed  Google Scholar 

  52. Rowe PS. X-linked rickets and tumor-acquired osteomalacia: PHEX and the missing link. Clin Exp Nephrol. 1998;2(3):183–93.

    Article  CAS  Google Scholar 

  53. Gupta A, Winer K, Econs M, Marx S, Collins M. FGF-23 is elevated by chronic hyperphosphatemia. J Clin Endocrinol Metabolism. 2004;89(9):4489–92.

    Article  CAS  Google Scholar 

  54. Yamashita H, Yamazaki Y, Hasegawa H, Yamashita T, Fukumoto S, Shigematsu T, Kazama JJ, Fukagawa M, Noguchi S. Fibroblast growth factor-23 (FGF23) in patients with transient hypoparathyroidism: its important role in serum phosphate regulation. Endocr J. 2007;54(3):465-70.

  55. Bai X, Miao D, Goltzman D, Karaplis AC. Early lethality in Hyp mice with targeted deletion of Pth gene. Endocrinology. 2007;148(10):4974–83.

    Article  CAS  PubMed  Google Scholar 

  56. Clarke BL, Vokes TJ, Bilezikian JP, Shoback DM, Lagast H, Mannstadt M. Effects of parathyroid hormone rhPTH (1–84) on phosphate homeostasis and vitamin D metabolism in hypoparathyroidism: REPLACE phase 3 study. Endocrine. 2017;55(1):273–82.

    Article  CAS  PubMed  Google Scholar 

  57. Clarke BL, Berg JK, Fox J, Cyran JA, Lagast H. Pharmacokinetics and pharmacodynamics of subcutaneous recombinant parathyroid hormone (1–84) in patients with hypoparathyroidism: an open-label, single-dose, phase I study. Clin Ther. 2014;36(5):722–36.

    Article  CAS  PubMed  Google Scholar 

  58. Sikjaer T, Rejnmark L, Rolighed L, Heickendorff L, Mosekilde L, Group HS. The effect of adding PTH (1–84) to conventional treatment of hypoparathyroidism: a randomized, placebo-controlled study. J Bone Miner Res. 2011;26(10):2358–70.

    Article  CAS  PubMed  Google Scholar 

  59. Gracia-Iguacel C, Gonzalez-Parra E, Rodriguez-Osorio L, Sanz AB, Almaden Y, de la Piedra C, Egido J, Rodriguez M, Ortiz A. Correction of hypocalcemia allows optimal recruitment of FGF-23-dependent phosphaturic mechanisms in acute hyperphosphatemia post-phosphate enema. J Bone Miner Metab. 2013;31(6):703-7.

  60. Rodriguez-Ortiz ME, Lopez I, Muñoz-Castañeda JR, Martinez-Moreno JM, Ramírez AP, Pineda C, Canalejo A, Jaeger P, Aguilera-Tejero E, Rodriguez M, Felsenfeld A. Calcium deficiency reduces circulating levels of FGF23. J Am Soc Nephrol. 2012;23(7):1190-7.

  61. Yamashita H, Yamashita T, Miyamoto M, Shigematsu T, Kazama JJ, Shimada T, Yamazaki Y, Fukumoto S, Fukagaw M, Noguchi S. Fibroblast growth factor (FGF)-23 in patients with primary hyperparathyroidism. Eur J Endocrinol. 2004;151(1):55-60.

  62. Ramon I, Kleynen P, Body JJ, Karmali R. Fibroblast growth factor 23 and its role in phosphate homeostasis. Eur J Endocrinol. 2010;162(1):1.

  63. Nakanishi S, Kazama JJ, Nii-Kono T, Omori K, Yamashita T, Fukumoto S, Gejyo F, Shigematsu T, Fukagawa M. Serum fibroblast growth factor-23 levels predict the future refractory hyperparathyroidism in dialysis patients. Kidney Int. 2005;67(3):1171-8.

  64. Sato T, Tominaga Y, Ueki T, Goto N, Matsuoka S, Katayama A, Haba T, Uchida K, Nakanishi S, Kazama JJ, Gejyo F. Total parathyroidectomy reduces elevated circulating fibroblast growth factor 23 in advanced secondary hyperparathyroidism. Am J Kidney Dis. 2004;44(3):481-7.

Download references

Acknowledgments

he authors wish to thank Mr. H. Argasi at the Research Consultation Center (RCC) of Shiraz University of Medical Sciences for his invaluable assistance in editing this manuscript.

Funding

There is no financial support.

Author information

Authors and Affiliations

  1. Shiraz Endocrinology and Metabolism Research Center, Shiraz University of Medical Sciences, P.O. Box: 71345-1744, Shiraz, Iran

    Forough Saki, Seyed Reza Kassaee, Azita Salehifar & Gholam Hossein Ranjbar Omrani

Authors
  1. Forough Saki
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Seyed Reza Kassaee
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Azita Salehifar
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Gholam Hossein Ranjbar Omrani
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

FS: design, data gathering, Analysis, preparing the manuscript. AS: design, data gathering, preparing the manuscript. SRK: design, data gathering, preparing the manuscript. GHRO: design, data gathering, preparing the manuscript and the correspondence. All authors have read and approved the manuscript.

Corresponding author

Correspondence to Gholam Hossein Ranjbar Omrani.

Ethics declarations

Ethics approval and consent to participate

Shiraz University of Medical Sciences local ethic committee and vice-chancellor of research at SUMS approved this study with number 1396-01-01-15805. All the patients signed a written informed consent form after a session explaining the aim, method and goal of the study for each participant.

Consent for publication

All the patients signed a written informed consent form to publish their data in manuscript after a session explaining the aim, method and goal of the study.

Competing interests

Gholamhossein Ranjbar Omrani, Azita Salehifar, Seyed Reza Kassaee and Forough Saki declare that they have no conflict of interest.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Saki, F., Kassaee, S.R., Salehifar, A. et al. Interaction between serum FGF-23 and PTH in renal phosphate excretion, a case-control study in hypoparathyroid patients. BMC Nephrol 21, 176 (2020). https://doi.org/10.1186/s12882-020-01826-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12882-020-01826-5

Keywords

BMC Nephrology

ISSN: 1471-2369

Contact us