scholarly journals HDAC6 inactivates Runx2 promoter to block osteogenesis of bone marrow stromal cells in age-related bone loss of mice

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Chao Ma ◽  
Juan Gao ◽  
Jun Liang ◽  
Weixiang Dai ◽  
Zhenfei Wang ◽  
...  

Abstract Background Senile osteoporosis can cause bone fragility and increased risk for fractures and has been one of the most prevalent and severe diseases affecting the elderly population worldwidely. The underlying mechanisms are currently intensive areas of investigation. In age-related bone loss, decreased bone formation overweighs increased bone resorption. The molecular mechanisms underlying defective bone formation in age-related bone loss are not completely understood. In particular, the specific role of histone acetylation in age-related bone loss has not been examined thoroughly. Methods We employed 6- and 18-month-old mice to investigate the mechanisms of defective bone formation in age-related bone loss. Bone marrow stromal cells (BMSCs) were induced to undergo in vitro osteogenic differentiation. Chromatin immunoprecipitation (ChIP) was used to investigate the binding of histone deacetylases (HDACs) on Runx2 promoter in BMSCs. Luciferase reporter and transient transfection assay were employed to study Runx2 gene expression modulation by HDAC and androgen receptor (AR). siRNA and HDAC6 inhibitor, Tubastatin A, were used to inhibit HDAC6 in vitro. And systemic administration of Tubastatin A was used to block HDAC6 in vivo. Results Age-related trabecular bone loss was observed in 18-month-old mice compared with 6-month-old mice. In vitro osteogenic differentiation potential of BMSCs from 18-month-old mice was weaker than 6-month-old mice, in which there was Runx2 expression inactivation in BMSCs of 18-month-old mice compared with 6-month-old mice, which was attributable to HDAC6-mediated histone hypoacetylation in Runx2 promoter. There was competitive binding of HDAC6 and AR on Runx2 promoter to modulate Runx2 expression in BMSCs. More importantly, through siRNA- or specific inhibitor-mediated HDAC6 inhibition, we could activate Runx2 expression, rescue in vitro osteogenesis potential of BMSCs, and alleviate in vivo age-related bone loss of mice. Conclusion HDAC6 accumulation and histone hypoacetylation on Runx2 promoter contributed to the attenuation of in vitro osteogenic differentiation potential of BMSCs from aged mice. Through HDAC6 inhibition, we could activate Runx2 expression and osteogenic differentiation potential of BMSCs from aged mice and alleviate the age-related bone loss of aged mice. Our study will benefit not only for understanding the age-related bone loss, but also for finding new therapies to treat senile osteoporosis.

Author(s):  
Hang Li ◽  
Jian Qu ◽  
Haihong Zhu ◽  
Jiaojiao Wang ◽  
Hao He ◽  
...  

Osteoporosis is a chronic age-related disease. During aging, bone marrow-derived mesenchymal stem cells (BMSCs) display increased adipogenic, along with decreased osteogenic, differentiation capacity. The aim of the present study was to investigate the effect of calcitonin gene-related peptide (CGRP) on the osteogenic and adipogenic differentiation potential of BMSC-derived osteoblasts. Here, we found that the level of CGRP was markedly lower in bone marrow supernatant from aged mice compared with that in young mice. In vitro experiments indicated that CGRP promoted the osteogenic differentiation of BMSCs while inhibiting their adipogenic differentiation. Compared with vehicle-treated controls, aged mice treated with CGRP showed a substantial promotion of bone formation and a reduction in fat accumulation in the bone marrow. Similarly, we found that CGRP could significantly enhance bone formation in ovariectomized (OVX) mice in vivo. Together, our results suggested that CGRP may be a key regulator of the age-related switch between osteogenesis and adipogenesis in BMSCs and may represent a potential therapeutic strategy for the treatment of age-related bone loss.


2019 ◽  
Vol 20 (24) ◽  
pp. 6229 ◽  
Author(s):  
Dijie Li ◽  
Ye Tian ◽  
Chong Yin ◽  
Ying Huai ◽  
Yipu Zhao ◽  
...  

Osteoporosis, a disease characterized by both loss of bone mass and structural deterioration of bone, is the most common reason for a broken bone among the elderly. It is known that the attenuated differentiation ability of osteogenic cells has been regarded as one of the greatest contributors to age-related bone formation reduction. However, the effects of current therapies are still unsatisfactory. In this study we identify a novel long noncoding RNA AK045490 which is correlated with osteogenic differentiation and enriched in skeletal tissues of mice. In vitro analysis of bone-derived mesenchymal stem cells (BMSCs) showed that AK045490 inhibited osteoblast differentiation. In vivo inhibition of AK045490 by its small interfering RNA rescued bone formation in ovariectomized osteoporosis mice model. Mechanistically, AK045490 inhibited the nuclear translocation of β-catenin and downregulated the expression of TCF1, LEF1, and Runx2. The results suggest that Lnc-AK045490 suppresses β-catenin/TCF1/Runx2 signaling and inhibits osteoblast differentiation and bone formation, providing a novel mechanism of osteogenic differentiation and a potential drug target for osteoporosis.


Author(s):  
Daqian Wan ◽  
Songtao Ai ◽  
Huoniu Ouyang ◽  
Liming Cheng

AbstractSenile osteoporosis can cause bone fragility and increased fracture risks and has been one of the most prevalent and severe diseases affecting the elderly population. Bone formation depends on the proper osteogenic differentiation of bone marrow stromal cells (BMSCs) in the bone marrow microenvironment, which is generated by the functional relationship among different cell types in the bone marrow. With aging, bone marrow provides signals that repress osteogenesis. Finding the signals that oppose BMSC osteogenic differentiation from the bone marrow microenvironment and identifying the abnormal changes in BMSCs with aging are key to elucidating the mechanisms of senile osteoporosis. In a pilot experiment, we found that 4-1BBL and 4-1BB were more abundant in bone marrow from aged (18-month-old) mice than young (6-month-old) mice. Meanwhile, significant bone loss was observed in aged mice compared with young mice. However, very little data have been generated regarding whether high-level 4-1BB/4-1BBL in bone marrow was associated with bone loss in aged mice. In the current study, we found upregulation of 4-1BB in the BMSCs of aged mice, which resulted in the attenuation of the osteogenic differentiation potential of BMSCs from aged mice via the p38 MAPK-Dkk1 pathway. More importantly, bone loss of aged mice could be rescued through the blockade of 4-1BB signaling in vivo. Our study will benefit not only our understanding of the pathogenesis of age-related trabecular bone loss but also the search for new targets to treat senile osteoporosis.


RSC Advances ◽  
2018 ◽  
Vol 8 (15) ◽  
pp. 8080-8088 ◽  
Author(s):  
Yuqin Shen ◽  
Yin Liu ◽  
Han Gao ◽  
Hongbo Fei ◽  
Wenwen Yu ◽  
...  

We employN-acetyl-l-leucine-modified polyethylenimine as an miR-34a carrier and evaluate its delivery ability, transfection efficiency, cytotoxicity and whether it enhances osteogenic differentiation and bone formationin vitroandin vivo.


2020 ◽  
Vol 21 (10) ◽  
pp. 3631 ◽  
Author(s):  
Raffaella Boggia ◽  
Federica Turrini ◽  
Alessandra Roggeri ◽  
Guendalina Olivero ◽  
Francesca Cisani ◽  
...  

The immune system and the central nervous system message each other to preserving central homeostasis. Both systems undergo changes during aging that determine central age-related defects. Ellagic acid (EA) is a natural product which is beneficial in both peripheral and central diseases, including aging. We analyzed the impact of the oral administration of a new oral ellagic acid micro-dispersion (EAm), that largely increased the EA solubility, in young and old mice. Oral EAm did not modify animal weight and behavioral skills in young and old mice, but significantly recovered changes in “ex-vivo, in vitro” parameters in old animals. Cortical noradrenaline exocytosis decreased in aged mice. EAm administration did not modify noradrenaline overflow in young animals, but recovered it in old mice. Furthermore, GFAP staining was increased in the cortex of aged mice, while IBA-1 and CD45 immunopositivities were unchanged when compared to young ones. EAm treatment significantly reduced CD45 signal in both young and old cortical lysates; it diminished GFAP immunopositivity in young mice, but failed to affect IBA-1 expression in both young and old animals. Finally, EAm treatment significantly reduced IL1beta expression in old mice. These results suggest that EAm is beneficial to aging and represents a nutraceutical ingredient for elders.


2019 ◽  
Vol 3 (s1) ◽  
pp. 24-24
Author(s):  
Rubens Sautchuk ◽  
Brianna H. Shares ◽  
Roman A. Eliseev

OBJECTIVES/SPECIFIC AIMS: The study aims to further investigate how cyclophilin D (CypD), the key mPTP opening regulator, affects BMSCs fate and to determine potential regulatory mechanisms involved in CypD regulation during osteogenesis. METHODS/STUDY POPULATION: We evaluated CypD mRNA expression in mouse BMSCs and in osteogenic-like (OL) cells during the course of OB differentiation. CypD protein level was also probed. Moreover, BMSCs had their mPTP activity recorded during osteoinduction. We further analyzed the effect of CypD genetic deletion on osteogenesis in vitro and in vivo. For our in vivo model, we performed the ectopic bone formation assay to asses differences in ossicle formation when CypD KO BMSCs were transplanted compared to wild type littermate BMSCs. In our in vitro model, we transfected OL cells with either CypD gain of function or CypD loss of function vector and measured their osteogenic differentiation potential. Additionally, we treated BMSCs with CypD inhibitor and compare to non-treated BMSCs for mineralization level. To determine potential regulatory mechanisms involved in CypD regulation, we analyzed the CypD gene (Ppif) promoter for potential transcription factor (TF) binding sites and found multiple Smad-binding elements within this promoter. Smads (Smad1, 5, 8) are TFs downstream from Bone Morphogenic Protein (BMP) signaling pathway that transmit cell differentiation signaling, and exert either activating or inhibitory effects on a variety of genes. We also transfect OL cells with Smad1 vector and analyzed for CypD mRNA levels. RESULTS/ANTICIPATED RESULTS: - Our data showed that CypD mRNA levels decreased in both primary cells and OL cells at day 7 and day 14 in osteogenic media. - Osteogenic induction also decreased mPTP activity. - In vivo ectopic bone formation assay showed increased ossicle fo DISCUSSION/SIGNIFICANCE OF IMPACT: Our data suggest that downregulation of CypD increases OB differentiation due to improved OxPhos activity led by mPTP closure. Our results corroborate reports of CypD downregulation and mPTP closure during neuronal differentiation in developing rat brains as well as in cardiomyocyte differentiation in developing mouse hearts. Our studies also suggest a yet unknown mechanism linking differentiation signaling with mitochondrial function – BMP/Smad mediated downregulation of CypD transcription. As initially mentioned, in a previous study, our lab showed that CypD KO mice present higher mitochondrial function and osteogenicity in aged BMSCs and less osteoporosis burden. Taken together, these results suggest that CypD can be a potential target to prevent bone loss in aging.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Dan Zhang ◽  
Kim De Veirman ◽  
Rong Fan ◽  
Qiang Jian ◽  
Yuchen Zhang ◽  
...  

Abstract Background Bone destruction is a hallmark of multiple myeloma (MM). It has been reported that proteasome inhibitors (PIs) can reduce bone resorption and increase bone formation in MM patients, but the underlying mechanisms remain unclear. Methods Mesenchymal stem cells (MSCs) were treated with various doses of PIs, and the effects of bortezomib or carfilzomib on endoplasmic reticulum (ER) stress signaling pathways were analyzed by western blotting and real-time PCR. Alizarin red S (ARS) and alkaline phosphatase (ALP) staining were used to determine the osteogenic differentiation in vitro. Specific inhibitors targeting different ER stress signaling and a Tet-on inducible overexpressing system were used to validate the roles of key ER stress components in regulating osteogenic differentiation of MSCs. Chromatin immunoprecipitation (ChIP) assay was used to evaluate transcription factor-promoter interaction. MicroCT was applied to measure the microarchitecture of bone in model mice in vivo. Results We found that both PERK-ATF4 and IRE1α-XBP1s ER stress branches are activated during PI-induced osteogenic differentiation. Inhibition of ATF4 or XBP1s signaling can significantly impair PI-induced osteogenic differentiation. Furthermore, we demonstrated that XBP1s can transcriptionally upregulate ATF4 expression and overexpressing XBP1s can induce the expression of ATF4 and other osteogenic differentiation-related genes and therefore drive osteoblast differentiation. MicroCT analysis further demonstrated that inhibition of XBP1s can strikingly abolish bortezomib-induced bone formation in mouse. Conclusions These results demonstrated that XBP1s is a master regulator of PI-induced osteoblast differentiation. Activation of IRE1α-XBP1s ER stress signaling can promote osteogenesis, thus providing a novel strategy for the treatment of myeloma bone disease.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Yu-Hee Kim ◽  
Kyung-Ah Cho ◽  
Hyun-Ji Lee ◽  
Minhwa Park ◽  
Han Su Kim ◽  
...  

The application of mesenchymal stem cells (MSCs) for treating bone-related diseases shows promising outcomes in preclinical studies. However, cells that are isolated and defined as MSCs comprise a heterogeneous population of progenitors. This heterogeneity can produce variations in the performance of MSCs, especially in applications that require differentiation potential in vivo, such as the treatment of osteoporosis. Here, we aimed to identify genetic markers in tonsil-derived MSCs (T-MSCs) that can predict osteogenic potential. Using a single-cell cloning method, we isolated and established several lines of nondifferentiating (ND) or osteoblast-prone (OP) clones. Next, we performed transcriptome sequencing of three ND and three OP clones that maintained the characteristics of MSCs and determined the top six genes that were upregulated in OP clones. Upregulation of WNT16 and DCLK1 expression was confirmed by real-time quantitative PCR, but only WNT16 expression was correlated with the osteogenic differentiation of T-MSCs from 10 different donors. Collectively, our findings suggest that WNT16 is a putative genetic marker that predicts the osteogenic potential of T-MSCs. Thus, examination of WNT16 expression as a selection criterion prior to the clinical application of MSCs may enhance the therapeutic efficacy of stem cell therapy for bone-related complications, including osteoporosis.


2010 ◽  
Vol 31 (2) ◽  
pp. 117-124 ◽  
Author(s):  
Feng Pan ◽  
Rui Zhang ◽  
Guang Wang ◽  
Yin Ding

The existence of PDLSCs [PDL (periodontal ligament) stem cells] in PDL has been identified and such cells may function in periodontal reconstruction, including bone formation. Oestrogens/ERs (oestrogen receptors; ERα and ERβ) exert important effects in bone formation, however, the relationship between ERs and PDLSCs has not been established. In the present study, PDLSCs were isolated and assays for detecting stem-cell biomarkers and multipotential differentiation potential confirmed the validity of human PDLSCs. The results of RT–PCR (reverse transcription–PCR) and Western blotting showed that ERα and ERβ were expressed at higher levels in PDLSCs as compared with PDLCs (PDL cells), and 17β-oestradiol obviously induced the osteogenic differentiation of PDLSCs in vitro. Furthermore, a pan-ER inhibitor or lentivirus-mediated siRNA (small interfering RNA) targeting ERα or ERβ blocked the oestrogen-induced osteogenic differentiation of PDLSCs. The results indicate that both ERα and ERβ were involved in the process of osteogenic differentiation of PDLSCs.


2021 ◽  
Vol 12 ◽  
Author(s):  
Baofeng Li ◽  
Renkai Wang ◽  
Xianyin Huang ◽  
Yongliang Ou ◽  
Zhenyu Jia ◽  
...  

Extracorporeal shock wave therapy (ESWT) has been identified to accelerate bone formation. However, detailed mechanism has not been fully explained. In this study, we found that ESWT promoted osteoblast formation in vitro. Local ESW treatment of femur increased bone formation in vivo. Furthermore, changing the density or frequency of energy, there was no statistical difference in osteogenic differentiation. Therapeutically, local ESW therapy relieved bone loss and increased the number of bone trabecular in a rabbit osteoporosis model and promoted endogenous levels of SMAD2 protein expression. Thus, ESWT may be a potential therapy by promoting osteoblast maturation through TGF-β/SMAD2 pathway.


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