scholarly journals Bone Mineral Density and Testicular Failure: Evidence for a Role of Vitamin D 25-Hydroxylase in Human Testis

2011 ◽  
Vol 96 (4) ◽  
pp. E646-E652 ◽  
Author(s):  
Carlo Foresta ◽  
Giacomo Strapazzon ◽  
Luca De Toni ◽  
Lisa Perilli ◽  
Antonella Di Mambro ◽  
...  

Abstract Working Hypothesis: Mutations in the CYP2R1 gene, highly expressed in the testis and encoding vitamin D 25-hydroxylase, result in a vitamin D deficiency and a defective calcium homeostasis leading to rickets. Objective: Our aim was to investigate CYP2R1 expression in pathological testis samples and relate this to vitamin D metabolism in testiculopathic patients. Design, Patients, Setting: Testis samples for in vitro study and 98 young men were transversally evaluated at Padova's Center for Male Gamete Cryopreservation. Methods: CYP2R1 mRNA expression and protein production were evaluated by quantitative RT-PCR, Western blot analysis, and immunofluorescence. Hormonal and bone-marker levels, and bone densitometry by dual-energy x-ray absorptiometry, were determined in patients with Sertoli-cell-only syndrome and severe hypospermatogenesis. Results: We found a lower gene and protein expression of CYP2R1 in samples with hypospermatogenesis and Sertoli-cell-only syndrome (P < 0.05) and a colocalization with INSL-3, a Leydig cell marker, at immunofluorescence. In all testiculopathic patients 25-hydroxyvitamin D levels were significantly lower and PTH levels higher compared to controls (P < 0.05). Furthermore, testiculopathic patients showed osteopenia and osteoporosis despite normal testosterone levels compared with controls both with increased bone-marker levels and altered dual-energy x-ray absorptiometry in the femoral neck and lumbar spine (for all parameters, P < 0.05). Conclusions: Our data show an association between testiculopathy and alteration of the bone status, despite unvaried androgen and estrogen levels and no other evident cause of vitamin D reduction. Further studies in larger cohorts are needed to confirm our results.

Endocrinology ◽  
2011 ◽  
Vol 152 (3) ◽  
pp. 1195-1195
Author(s):  
Carlo Foresta ◽  
Giacomo Strapazzon ◽  
Luca De Toni ◽  
Lisa Perilli ◽  
Antonella Di Mambro ◽  
...  

Abstract Working Hypothesis: Mutations in the CYP2R1 gene, highly expressed in the testis and encoding vitamin D 25-hydroxylase, result in a vitamin D deficiency and a defective calcium homeostasis leading to rickets. Objective: Our aim was to investigate CYP2R1 expression in pathological testis samples and relate this to vitamin D metabolism in testiculopathic patients. Design, Patients, Setting: Testis samples for in vitro study and 98 young men were transversally evaluated at Padova's Center for Male Gamete Cryopreservation. Methods: CYP2R1 mRNA expression and protein production were evaluated by quantitative RT-PCR, Western blot analysis, and immunofluorescence. Hormonal and bone-marker levels, and bone densitometry by dual-energy x-ray absorptiometry, were determined in patients with Sertoli-cell-only syndrome and severe hypospermatogenesis. Results: We found a lower gene and protein expression of CYP2R1 in samples with hypospermatogenesis and Sertoli-cell-only syndrome (P < 0.05) and a colocalization with INSL-3, a Leydig cell marker, at immunofluorescence. In all testiculopathic patients 25-hydroxyvitamin D levels were significantly lower and PTH levels higher compared to controls (P < 0.05). Furthermore, testiculopathic patients showed osteopenia and osteoporosis despite normal testosterone levels compared with controls both with increased bone-marker levels and altered dual-energy x-ray absorptiometry in the femoral neck and lumbar spine (for all parameters, P < 0.05). Conclusions: Our data show an association between testiculopathy and alteration of the bone status, despite unvaried androgen and estrogen levels and no other evident cause of vitamin D reduction. Further studies in larger cohorts are needed to confirm our results.


2021 ◽  
pp. 23-30
Author(s):  
S.T. Muratova ◽  

The development of the skeletal system occur during childhood. Thyroid hormones play an important role in the skeleton's maturation and maintenance of the structure and mass of bones. Juvenile hyperthyroidism affects bone metabolism. This study aimed to identify abnormalities in bone mineral density and the level of calciotropic hormones in juvenile hyperthyroidism to further improve the diagnosis of complications of juvenile hyperthyroidism. Materials and methods. The study was conducted by 21 health controls and 71 children and adolescents with juvenile hyperthyroidism. Anthropometric indicators were calculated using the WHO Anthro Plus personal computer software. Thyroid status and thyroid antibodies, osteocalcin, parathyroid hormone, vitamin D, calcium, phosphorus, alkaline phosphatase were determined using a closed-type immunochemistry analyzer Cobas e 411 Hitachi company Hoffman Le Roche (Switzerland) and its reagents. Bone mineral density was evaluated by dual-energy absorptiometry on a Stratos X-ray densitometer from Diagnostic Medical Systems, France. Results. In juvenile hypertrichosis, in comparison with the control, significantly low values of vitamin D and calcium in the blood serum were noted, the mean values of osteocalcin and alkaline phosphatase were substantially higher. There was no significant difference in the levels of parathyroid hormone and phosphorus in the blood serum in the compared groups. In 45.1% of patients, a decrease in bone mass was diagnosed compared to the age norm. A reliable direct correlation of vitamin D and calcium with bone density was revealed in all X-ray densitometry parameters and a reliable inverse correlation of osteocalcin, alkaline phosphatase and bone mineral density. Osteocalcin had a stronger inverse correlation with all dual-energy X-ray absorptiometry parameters and became a better biomarker than alkaline phosphatase. Conclusions. There is a decrease in bone mineral density in children with juvenile hyperthyroidism. Changes in the level of calciotropic hormones indicate a deranged bone metabolism. Serum osteocalcin can be used as a biomarker of bone metabolism in children with juvenile hyperthyroidism. It is recommended to assess the bones' condition during the initial examination of children with juvenile hyperthyroidism. The study was carried out following the principles of the Declaration of Helsinki. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the parents of the children was obtained for the research. The author declares no conflicts of interest. Key words: juvenile hyperthyroidism, children, adolescents, bone mineral density; dual energy X-ray absorptiometry, osteocalcin, vitamin D.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Talles Bazeia Lima ◽  
Lívia Alves Amaral Santos ◽  
Hélio Rubens de Carvalho Nunes ◽  
Giovanni Faria Silva ◽  
Carlos Antonio Caramori ◽  
...  

AbstractDespite the high prevalence of osteoporosis in liver cirrhosis, the indication of bisphosphonates for patients with esophageal varices has been avoided due to risk of digestive mucosal damage. Therefore, this study aimed to evaluate the safety profile of risedronate treatment for patients with osteoporosis, liver cirrhosis and esophageal varices with low risk of bleeding. A total of 120 patients were allocated into two groups according to their bone mineral density measured by dual-energy X-ray absorptiometry. In the intervention group, 57 subjects with osteoporosis received oral risedronate at 35 mg weekly plus daily calcium and vitamin D supplementation. In the control group, 63 subjects with osteopenia received only calcium and vitamin D. The groups received the treatment for one year and underwent surveillance endoscopies at six and 12 months, as well as a control dual-energy X-ray absorptiometry after a 12-month follow-up. The study received Institutional Review Board approval. The groups had not only comparable Model for End-stage Liver Disease score and esophageal varices degree, but also similar incidence of digestive adverse effects. A significant improvement was achieved in the intervention group in the lumbar spine T score (p < 0.001). The results suggest that risedronate may be safely used in liver cirrhosis and esophageal varices with low bleeding risk under endoscopic surveillance, thus allowing bone mass recovery.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 227.2-228
Author(s):  
D. Claire ◽  
M. Geoffroy ◽  
L. Kanagaratnam ◽  
C. Isabelle ◽  
A. Hittinger ◽  
...  

Background:Dual energy X-ray absoprtiometry is the reference method to mesure bone mineral density (1). Loss of bone mineral density is significant if it exceeds the least significant change. The threshold value used in general population is 0,03 g/cm2 (2). Patients with obesity are known for having a higher bone mineral density due to metabolism and physiopathology characteristics (3,4).Objectives:The aim of our study was to determine the least significant change in bone densitometry in patients with obesity.Methods:We conducted an interventionnal study in 120 patients with obesity who performed a bone densitometry. We measured twice the bone mineral density at the lumbar spine, the femoral neck and the total hip in the same time (5,6). We determined the least significant change in bone densitometry from each pair of measurements, using the Bland and Altman method. We also determined the least significant change in bone densitometry according to each stage of obesity.Results:The least significant change in bone densitometry in patients with obesity is 0,046g/cm2 at the lumbar spine, 0.069 g/cm2 at the femoral neck and 0.06 g/cm2 at the total hip.Conclusion:The least significant change in bone densitometry in patients with obesity is higher than in general population. These results may improve DXA interpretation in this specific population, and may personnalize their medical care.References:[1]Lees B, Stevenson JC. An evaluation of dual-energy X-ray absorptiometry and comparison with dual-photon absorptiometry. Osteoporos Int. mai 1992;2(3):146-52.[2]Briot K, Roux C, Thomas T, Blain H, Buchon D, Chapurlat R, et al. Actualisation 2018 des recommandations françaises du traitement de l’ostéoporose post-ménopausique. Rev Rhum. oct 2018;85(5):428-40.[3]Shapses SA, Pop LC, Wang Y. Obesity is a concern for bone health with aging. Nutr Res N Y N. mars 2017;39:1-13.[4]Savvidis C, Tournis S, Dede AD. Obesity and bone metabolism. Hormones. juin 2018;17(2):205-17.[5]Roux C, Garnero P, Thomas T, Sabatier J-P, Orcel P, Audran M, et al. Recommendations for monitoring antiresorptive therapies in postmenopausal osteoporosis. Jt Bone Spine Rev Rhum. janv 2005;72(1):26-31.[6]Ravaud P, Reny JL, Giraudeau B, Porcher R, Dougados M, Roux C. Individual smallest detectable difference in bone mineral density measurements. J Bone Miner Res. août 1999;14(8):1449-56.Disclosure of Interests:None declared.


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