Adipocyte-secreted factors increase osteoblast proliferation and the OPG/RANKL ratio to influence osteoclast formation

Ziora

Oświęcimska

et al. 2016

Introduction: Numerous investigations, and especially in vitro studies, indicate that TGF-β1 may act as an important regulator of bone remodelling. Thus, it could be expected that disturbances of this cytokine production observed by several researchers might play a role in the mechanism leading to the development of osteoporosis in girls with anorexia nervosa (AN). The aim of the study was to determine whether 1) girls with AN exhibited a relationship between TGF-β1 and bone metabolism (as assessed based on serum OC and CTx concentrations) and 2) whether OPG and sRANKL might modify the possible relationship between TGF-β1 and bone metabolism. Material and methods: Serum concentrations of TGF-β, OC, CTx, OPG, and its soluble ligand sRANKL were determined by ELISA in 60 girls with AN and in 20 healthy controls (C). All study participants were aged 13 to 17 years. Results: Body weight, BMI, BMI-SDS and the Cole index, serum TGF-β1, OC, CTx, and the OPG/sRANKL ratio were significantly reduced, while OPG and sRANKL levels were significantly increased, in girls with AN compared to healthy participants. BMI and the Cole index correlated negatively and significantly with serum CTx and OPG (AN group) or CTx only (groups C and C + AN). Girls with AN showed a positive and significant correlation between the Cole index and serum TGF-β1. The combination group (C + AN) showed a positive and significant correlation between BMI, the Cole index, and the OPG/sRANKL ratio and TGF-β1 concentration, while TGF-β1 correlated positively and significantly with OC concentrations and the OPG/sRANKL ratio. The Cole index and BMI were identified to be significant and independent predictors of CTx (C, AN, and C+AN groups) and OPG (AN group); the Cole index, BMI, and TGF-β1 independently predicted the OPG/sRANKL ratio (C, AN, and C + AN groups); TGF-β1 was found to be an independent predictor of OC (C + AN group). Conclusions: Changes in bone markers, OPG, and/or OPG/sRANKL ratio observed in girls with AN are associated with changes in serum TGF-β1 concentrations. TGF-β1 suppression in girls with AN might lead to disturbances in the relationship between bone metabolism and the OPG/sRANKL system, which, in turn, might compromise the mechanism compensating for bone remodelling disturbances. (Endokrynol Pol 2016; 67 (5): 493-500)

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Section: Discussionmentioning

confidence: 97%

TGF-β1, metabolizm kostny, osteoprotegeryna i rozpuszczalny ligand receptora aktywatora czynnika jądrowego-B u dziewcząt z jadłowstrętem psychicznym

Ziora

Oświęcimska

et al. 2016

show abstract

“…The results of in vitro investigations also indicate that some adipocyte-secreted factors, including the abovementioned pro-inflammatory cytokines, might modify the balance of OPG/RANKL [40][41][42]. It was shown that human adipocytes regulated the expression of OPG and RANKL in human osteoblastic cell lines in vitro.…”

Section: Prace Oryginalnementioning

confidence: 94%

“…The OPG/RANKL ratio in primary human preosteoblasts increased (mRNA and protein) when stimulated with adipocyte-secreted factors. Osteoblasts that were pre-stimulated with adipocyte-secreted factors inhibited the formation of osteoclasts [42].…”

Section: Prace Oryginalnementioning

confidence: 99%

See 1 more Smart Citation

Wybrane cytokiny prozapalne, metabolizm kostny, osteoprotegeryna i ligand receptora aktywatora czynnika jądrowego-kB u dziewcząt z jadłowstrętem psychicznym

Ziora

Oświęcimska

et al. 2015

“…As particular adipocytokines may exert a similar or opposite effect on bone tissue cells and OPG and/or RANKL expression in human osteoablasts in vitro [11-22, 24, 26], it is quite difficult to predict the net effect of their actions on the balance of the OPG/ /RANKL system and/or bone remodelling and bone mass in vivo. The most recent in vitro studies [24,26] seem to indicate a final stimulatory effect. An et al [24] found OPG and RANKL expression in 3T3L1 murine adipocytes.…”

Section: Prace Oryginalnementioning

confidence: 97%

Wybrane hormony tkanki tłuszczowej, metabolizm kostny a osteoprotegeryna i ligand receptora aktywatora czynnika jądrowego-kB u otyłych kobiet po menopauzie

Świętochowska

Marek

et al. 2015