skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling

Abstract

Cytosolic malate dehydrogenase (malate dehydrogenase 1, MDH1) plays pivotal roles in the malate/aspartate shuttle that might modulate metabolism between the cytosol and mitochondria. In this study, we investigated the role of MDH1 in osteoclast differentiation and formation. MDH1 expression was induced by receptor activator of nuclear factor kappa-B ligand (RANKL) treatment. Knockdown of MDH1 by infection with retrovirus containing MDH1-specific shRNA (shMDH1) reduced mature osteoclast formation and bone resorption activity. Moreover, the expression of marker genes associated with osteoclast differentiation was downregulated by shMDH1 treatment, suggesting a role of MDH1 in osteoclast differentiation. In addition, intracellular ATP production was reduced following the activation of adenosine 5′ monophosphate-activated protein kinase (AMPK), a cellular energy sensor and negative regulator of RANKL-induced osteoclast differentiation, in shMDH1-infected osteoclasts compared to control cells. In addition, the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor of osteoclastogenesis, was decreased with MDH1 knockdown during RANKL-mediated osteoclast differentiation. These findings provide strong evidence that MDH1 plays a critical role in osteoclast differentiation and function via modulation of the intracellular energy status, which might affect AMPK activity and NFATc1 expression.

Authors:
 [1];  [1];  [2];  [3];  [1];  [2];  [1];  [2];  [4]
  1. Department of Oral Microbiology and Immunology, College of Dentistry, Wonkwang University, Iksan, Jeonbuk 54538 (Korea, Republic of)
  2. (CMFR), School of Medicine, Wonkwang University, Iksan, Jeonbuk 54538 (Korea, Republic of)
  3. Center for Metabolic Function Regulation (CMFR), School of Medicine, Wonkwang University, Iksan, Jeonbuk 54538 (Korea, Republic of)
  4. (Korea, Republic of)
Publication Date:
OSTI Identifier:
22598772
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 475; Journal Issue: 1; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ADENOSINE; ATP; LIGANDS; METABOLISM; MITOCHONDRIA; MODULATION; RABBIT TUBES; RECEPTORS; SENSORS; SKELETON; TRANSCRIPTION; TRANSCRIPTION FACTORS

Citation Formats

Oh, Se Jeong, Gu, Dong Ryun, Center for Metabolic Function Regulation, Jin, Su Hyun, Park, Keun Ha, Center for Metabolic Function Regulation, Lee, Seoung Hoon, E-mail: leesh2@wku.ac.kr, Center for Metabolic Function Regulation, and Wonkwang Institute of Biomaterials and Implant, Wonkwang University, Iksan, Jeonbuk 54538. Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling. United States: N. p., 2016. Web. doi:10.1016/J.BBRC.2016.05.055.
Oh, Se Jeong, Gu, Dong Ryun, Center for Metabolic Function Regulation, Jin, Su Hyun, Park, Keun Ha, Center for Metabolic Function Regulation, Lee, Seoung Hoon, E-mail: leesh2@wku.ac.kr, Center for Metabolic Function Regulation, & Wonkwang Institute of Biomaterials and Implant, Wonkwang University, Iksan, Jeonbuk 54538. Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling. United States. doi:10.1016/J.BBRC.2016.05.055.
Oh, Se Jeong, Gu, Dong Ryun, Center for Metabolic Function Regulation, Jin, Su Hyun, Park, Keun Ha, Center for Metabolic Function Regulation, Lee, Seoung Hoon, E-mail: leesh2@wku.ac.kr, Center for Metabolic Function Regulation, and Wonkwang Institute of Biomaterials and Implant, Wonkwang University, Iksan, Jeonbuk 54538. 2016. "Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling". United States. doi:10.1016/J.BBRC.2016.05.055.
@article{osti_22598772,
title = {Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling},
author = {Oh, Se Jeong and Gu, Dong Ryun and Center for Metabolic Function Regulation and Jin, Su Hyun and Park, Keun Ha and Center for Metabolic Function Regulation and Lee, Seoung Hoon, E-mail: leesh2@wku.ac.kr and Center for Metabolic Function Regulation and Wonkwang Institute of Biomaterials and Implant, Wonkwang University, Iksan, Jeonbuk 54538},
abstractNote = {Cytosolic malate dehydrogenase (malate dehydrogenase 1, MDH1) plays pivotal roles in the malate/aspartate shuttle that might modulate metabolism between the cytosol and mitochondria. In this study, we investigated the role of MDH1 in osteoclast differentiation and formation. MDH1 expression was induced by receptor activator of nuclear factor kappa-B ligand (RANKL) treatment. Knockdown of MDH1 by infection with retrovirus containing MDH1-specific shRNA (shMDH1) reduced mature osteoclast formation and bone resorption activity. Moreover, the expression of marker genes associated with osteoclast differentiation was downregulated by shMDH1 treatment, suggesting a role of MDH1 in osteoclast differentiation. In addition, intracellular ATP production was reduced following the activation of adenosine 5′ monophosphate-activated protein kinase (AMPK), a cellular energy sensor and negative regulator of RANKL-induced osteoclast differentiation, in shMDH1-infected osteoclasts compared to control cells. In addition, the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor of osteoclastogenesis, was decreased with MDH1 knockdown during RANKL-mediated osteoclast differentiation. These findings provide strong evidence that MDH1 plays a critical role in osteoclast differentiation and function via modulation of the intracellular energy status, which might affect AMPK activity and NFATc1 expression.},
doi = {10.1016/J.BBRC.2016.05.055},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 475,
place = {United States},
year = 2016,
month = 6
}
  • The crucial role of p38 mitogen-activated protein kinase for osteoclast differentiation has been suggested from studies with specific pharmacological inhibitors and dominant-negative forms of p38. However, the targets through which p38 regulates osteoclast differentiation have not been clearly revealed. Here, we show that inhibition of p38 activity with SB203580 reduced osteoclastogenesis from primary precursor cells, with concomitant suppression in the induction of both c-Fos and nuclear factor of activated T cells (NFAT) c1 by receptor activator of nuclear factor {kappa}B ligand (RANKL), the key osteoclast differentiation factor. Overexpression of dominant-negative forms of p38 upstream kinases MKK3 and MKK6 elicited similarmore » reduction in RANKL-stimulated elevation of c-Fos and NFATc1. Interestingly, overexpression of c-Fos restored RANKL-induced osteoclast differentiation from and NFATc1 expression in SB203580-treated precursor cells. Our results demonstrate a previously unknown function of the p38 pathway in up-regulating c-Fos and NFATc1 expression during RANKL-induced osteoclastogenesis.« less
  • Highlights: •AG490 inhibits RANKL-induced osteoclastogenesis in RAW264.7 cells. •AG490 affects cell proliferation and cell cycle distribution. •AG490 reduces NFATc1 expression during RANKL-induced osteoclastogenesis. •AG490 disrupts the activation of RANKL-mediated JAK2/STAT3 signaling pathway. •STAT3 depletion partly mimics the effect of AG490 on RANKL-induced osteoclastogenesis. -- Abstract: Commonly, JAK/STAT relays cytokine signals for cell activation and proliferation, and recent studies have shown that the elevated expression of JAK/STAT is associated with the immune rejection of allografts and the inflammatory processes of autoimmune disease. However, the role which JAK2/STAT3 signaling plays in the receptor activator of nuclear factor-κB ligand (RANKL)-mediated osteoclastogenesis is unknown.more » In this study, we investigated the effects of AG490, specific JAK2 inhibitor, on osteoclast differentiation in vitro. AG490 significantly inhibited osteoclastogenesis in murine osteoclast precursor cell line RAW264.7 induced by RANKL. AG490 suppressed cell proliferation and delayed the G1 to S cell cycle transition. Furthermore, AG490 also suppressed the expression of nuclear factor of activated T cells (NFAT) c1 but not c-Fos in RAW264.7. Subsequently, we investigated various intracellular signaling components associated with osteoclastogenesis. AG490 had no effects on RANKL-induced activation of Akt, ERK1/2. Interestingly, AG490 partly inhibited RANKL-induced phosphorylation of Ser{sup 727} in STAT3. Additionally, down-regulation of STAT3 using siRNA resulted in suppression of TRAP, RANK and NFATc1 expression. In conclusion, we demonstrated that AG490 inhibited RANKL-induced osteoclastogenesis by suppressing NFATc1 production and cell proliferation via the STAT3 pathway. These results suggest that inhibition of JAK2 may be useful for the treatment of bone diseases characterized by excessive osteoclastogenesis.« less
  • Highlights: Black-Right-Pointing-Pointer CXCR6 is down-regulated during RANKL-induced osteoclastogenesis in RAW264.7 cells. Black-Right-Pointing-Pointer CXCR6 reduction was nearly reversed by inhibition of JAK2/STAT3 signaling pathway. Black-Right-Pointing-Pointer CXCL16 alone does not positively regulate osteoclastogenesis. -- Abstract: The receptor activator of nuclear factor-{kappa}B ligand (RANKL), as a member of the tumor necrosis factor (TNF) family, plays an essential role in osteoclast differentiation and function. Chemokines and their receptors have recently been shown to play critical roles in osteoclastogenesis, however, whether CXCL16-CXCR6 plays role in RANKL-mediated osteoclastogenesis is unknown. In this study, we first reported that RANKL decreased CXCR6 in a dose-dependent manner, which maymore » be through deactivation of Akt and STAT3 signaling induced by CXCL16. Interestingly, RANKL-mediated CXCR6 reduction may be associated to the activation of STAT3 by phosphorylation. When STAT3 activation was blocked by JAK2/STAT3 inhibitor AG490, RANKL failed to shut down CXCR6 expression during osteoclastogenesis. However, CXCL16 alone did not augment RANKL-mediated osteoclast differentiation and did not alter RANKL-receptor RANK mRNA expression. These results demonstrate that reduction of CXCL16-CXCR6 is critical in RANKL-mediated osteoclastogenesis, which is mainly through the activation of JAK2/STAT3 signaling. CXCL16-CXCR6 axis may become a novel target for the therapeutic intervention of bone resorbing diseases such as rheumatoid arthritis and osteoporosis.« less
  • Receptor activator of nuclear factor-κB ligand (RANKL) is a key factor in the differentiation and activation of osteoclasts. Echinocystic acid (EA), a pentacyclic triterpene isolated from the fruits of Gleditsia sinensis Lam, was reported to prevent reduction of bone mass and strength and improve the cancellous bone structure and biochemical properties in ovariectomy rats. However, the molecular mechanism of EA on the osteoclast formation has not been reported. The purpose of this study was to investigate the effects and mechanism of EA on RANKL-induced osteoclastogenesis. Our results showed that EA inhibited the formation of osteoclast, as well as the expressionmore » of osteoclastogenesis-related marker proteins in bone marrow macrophages (BMMs). At molecular levels, EA inhibited RANKL-induced NF-κB activation and ERK phosphorylation in BMMs. In conclusion, the present study demonstrated that EA can suppress osteoclastogenesis in vitro. Moreover, we clarified that these inhibitory effects of EA occur through suppression of NF-κB and ERK activation. Therefore, EA may be a potential agent in the treatment of osteoclast-related diseases such as osteoporosis. - Highlights: • EA inhibited the formation of osteoclast in BMMs. • EA inhibits the expression of osteoclastogenesis-related marker proteins in BMMs. • EA inhibits RANKL-induced NF-κB activation in BMMs. • EA inhibits RANKL-induced ERK phosphorylation in BMMs.« less
  • This article reports on the molecular cloning and mapping of a human cDNA for cytosolic malate dehydrogenase to human chromosome 2p15 using fluorescence in situ hybridization. The amino acid sequence of this protein was compared to that in the mouse. Expression of this gene is greatest in heart and skeletal muscle of adult human tissues. 6 refs., 2 figs.