scholarly journals LIM domain proteins Pinch1/2 regulate chondrogenesis and bone mass in mice

Bone Research ◽  
2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Yiming Lei ◽  
Xuekun Fu ◽  
Pengyu Li ◽  
Sixiong Lin ◽  
Qinnan Yan ◽  
...  

Abstract The LIM domain-containing proteins Pinch1/2 regulate integrin activation and cell–extracellular matrix interaction and adhesion. Here, we report that deleting Pinch1 in limb mesenchymal stem cells (MSCs) and Pinch2 globally (double knockout; dKO) in mice causes severe chondrodysplasia, while single mutant mice do not display marked defects. Pinch deletion decreases chondrocyte proliferation, accelerates cell differentiation and disrupts column formation. Pinch loss drastically reduces Smad2/3 protein expression in proliferative zone (PZ) chondrocytes and increases Runx2 and Col10a1 expression in both PZ and hypertrophic zone (HZ) chondrocytes. Pinch loss increases sclerostin and Rankl expression in HZ chondrocytes, reduces bone formation, and increases bone resorption, leading to low bone mass. In vitro studies revealed that Pinch1 and Smad2/3 colocalize in the nuclei of chondrocytes. Through its C-terminal region, Pinch1 interacts with Smad2/3 proteins. Pinch loss increases Smad2/3 ubiquitination and degradation in primary bone marrow stromal cells (BMSCs). Pinch loss reduces TGF-β-induced Smad2/3 phosphorylation and nuclear localization in primary BMSCs. Interestingly, compared to those from single mutant mice, BMSCs from dKO mice express dramatically lower protein levels of β-catenin and Yap1/Taz and display reduced osteogenic but increased adipogenic differentiation capacity. Finally, ablating Pinch1 in chondrocytes and Pinch2 globally causes severe osteopenia with subtle limb shortening. Collectively, our findings demonstrate critical roles for Pinch1/2 and a functional redundancy of both factors in the control of chondrogenesis and bone mass through distinct mechanisms.

2020 ◽  
Vol 29 ◽  
pp. 096368972093441 ◽  
Author(s):  
Yadong Luo ◽  
Huan Ji ◽  
Yan Cao ◽  
Xu Ding ◽  
Meng Li ◽  
...  

In this study, we assessed the ability of miR-26b-5p to regulate T cell factor 4 (TCF-4) expression and thereby control human adipose-derived mesenchymal stem cell (hADMSC) adipogenic differentiation. Adipogenic medium was used to induce hADMSC differentiation over a 6-d period. The ability of miR-26b-5p to interact with the TCF-4 mRNA was confirmed through both predictive bioinformatics analyses and luciferase reporter assays. Immunofluorescent staining was used to visualize the impact of miR-26b-5p inhibition or overexpression on TCF-4 and β-catenin levels in hADMSCs. Further functional analyses were conducted by transfecting these cells with siRNAs specific for TCF-4 and β-catenin. Adipogenic marker and Wnt/β-catenin pathway gene expression levels were assessed via real-time polymerase chain reaction and western blotting. β-catenin localization was assessed via immunofluorescent staining. As expected, our adipogenic media induced the adipocytic differentiation of hADMSCs. In addition, we confirmed that TCF-4 is an miR-26b-5p target gene in these cells, and that protein levels of both TCF-4 and β-catenin were reduced when these cells were transfected with miR-26b-5p mimics. Overexpression of this microRNA also enhanced hADMSC adipogenesis, whereas TCF-4 and β-catenin overexpression inhibited this process. The enhanced hADMSC adipogenic differentiation that was observed following TCF-4 or β-catenin knockdown was partially reversed when miR-26b-5p expression was inhibited. We found that miR-26b-5p serves as a direct negative regulator of TCF-4 expression within hADMSCs, leading to inactivation of the Wnt/β-catenin pathway and thereby promoting the adipogenic differentiation of these cells in vitro.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii167-ii167
Author(s):  
Lili Sun ◽  
Ming Li

Abstract The four and a half LIM domain 1 (FHL1) has been considered as a tumor suppressor protein in multiple cancers. Here, we show that FHL1 plays a tumor-promoting role in glioblastoma, the most common and incurable brain cancer. Overexpression of FHL1 promotes the growth, migration, and invasion of GBM cells in vivo and in vitro. In contrast, FHL1 silencing exhibits the opposite effects. Mechanically, FHL1 upregulates EGFR expression and activates the downstream AKT / ERK1 / 2 / STAT3 signaling pathways. We further demonstrated that SP1 can also be induced by FHL1 expression, and FHL1 interacts with SP1 to upregulate EGFR expression at both mRNA and protein levels, leading to glioblastoma malignancy. Clinically, FHL1 is highly expressed in glioblastoma and shows positive correlation with EGFR and SP1 in GBM specimens. Our results suggest the key role of FHL1 in the expression of EGFR and highlight the translation potential of inhibiting FHL1 as a treatment for glioblastoma.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Takujiro Homma ◽  
Toshihiro Kurahashi ◽  
Naoki Ishii ◽  
Nobuyuki Shirasawa ◽  
Junichi Fujii

Abstract PRDX4, a member of peroxiredoxin family, is largely concentrated in the endoplasmic reticulum (ER) and plays a pivotal role in the redox relay during oxidative protein folding as well as in peroxidase reactions. A testis-specific PRDX4 variant transcript (PRDX4t) lacks the conventional exon 1, which encodes the signal peptide that is required for entry into the ER lumen, but instead carries alternative exon 1, which is transcribed from the upstream promoter in a testis-specific manner and results in the PRDX4t protein being localized in the cytosol. However, the potential roles of PRDX4t in male genital action remain unknown. Using a CRISPR/Cas9 system, we first disrupted the testis-specific promoter/exon 1 and generated mice that were specifically deficient in PRDX4t. The resulting PRDX4t knockout (KO) mice underwent normal spermatogenesis and showed no overt abnormalities in the testis. Mating PRDX4t KO male mice with wild-type (WT) female mice produced normal numbers of offspring, indicating that a PRDX4t deficiency alone had no effect on fertility in the male mice. We then generated mice lacking both PRDX4 and PRDX4t by disrupting exon 2, which is communal to these variants. The resulting double knockout (DKO) mice were again fertile, and mature sperm isolated from the epididymis of DKO mice exhibited a normal fertilizing ability in vitro. In the meantime, the protein levels of glutathione peroxidase 4 (GPX4), which plays an essential role in the disulfide bond formation during spermatogenesis, were significantly increased in the testis and caput epididymis of the DKO mice compared with the WT mice. Based on these results, we conclude that the disruption of the function of PRDX4t in the spermatogenic process appears to be compensated by other factors including GPX4.


Genes ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 453
Author(s):  
Xiaoyu Wang ◽  
Jing Yang ◽  
Ying Yao ◽  
Xin’E Shi ◽  
Gongshe Yang ◽  
...  

The meat quality of animal products is closely related to the intramuscular fat content. Aquaglyceroporin (AQP) defines a class of water/glycerol channels that primarily facilitate the passive transport of glycerol and water across biological membranes. In this study, the AQP3 protein of the AQP family was mainly studied in the adipogenic function of intramuscular adipocytes in pigs. Here, we found that AQP3 was increased at both mRNA and protein levels upon adipogenic stimuli in porcine intramuscular adipocytes in vitro. Western blot results showed knockdown of AQP3 by siRNA significantly suppressed the expression of adipogenic genes (PPARγ, aP2, etc.), repressed Akt phosphorylation, as well as reducing lipid accumulation. Furthermore, deletion of AQP3 by siRNA significantly downregulated expression of cell cycle genes (cyclin D, E), and decreased the number of EdU-positive cells as well as cell viability. Collectively, our data indicate that AQP3 is of great importance in both adipogenic differentiation and proliferation in intramuscular adipocytes, providing a potential target for modulating fat infiltration in skeletal muscles.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhen-Xiong Jin ◽  
Xin-Yuan Liao ◽  
Wei-Wei Da ◽  
Yong-Jian Zhao ◽  
Xiao-Feng Li ◽  
...  

Abstract Introduction Osthole has a potential therapeutic application for anti-osteoporosis. The present study verified whether osthole downregulates osteoclastogenesis via targeting OPG. Methods In vivo, 12-month-old male mice were utilized to evaluate the effect of osthole on bone mass. In vitro, bone marrow stem cells (BMSCs) were isolated and extracted from 3-month-old OPG−/− mice and the littermates of OPG+/+ mice. Calvaria osteoblasts were extracted from 3-day-old C57BL/6J mice or 3-day-old OPG−/− mice and the littermates of OPG+/+ mice. Results Osthole significantly increased the gene and protein levels of OPG in primary BMSCs in a dose-dependent manner. The deletion of the OPG gene did not affect β-catenin expression. The deletion of the β-catenin gene inhibited OPG expression in BMSCs, indicating that osthole stimulates the expression of OPG via activation of β-catenin signaling. Conclusion Osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential drug for the senile osteoporosis.


2020 ◽  
Author(s):  
Yadong Luo ◽  
Huan Ji ◽  
Yan Cao ◽  
Xu Ding ◽  
Meng Li ◽  
...  

Abstract Background: Our study was designed to investigate the role of miR-26b-5p on TCF-4, affecting the adipogenic differentiation of human adipose-derived mesenchymal stem cells (hADMSCs). METHODS: The adipogenic differentiation of hADMSCs was induced by adipogenic medium for 6 days (d). Bioinformatic and dual-luciferase analyses were used to confirm the relationship between TCF-4 and miR-26b-5p. Immunofluorescence was used to detect the effect of miR-26b-5p on TCF-4 and β-catenin in hADMSCs transfected with miR-26b-5p mimic and inhibitor. Mimic, inhibitor, and small interfering RNA (siRNA) transfected in hADMSCs to against LEF1 and β-catenin. Quantitative real-time PCR and western blotting were used to examine the adipogenic markers and Wnt/β-catenin pathway at the mRNA and protein levels, respectively. Immunofluorescence was performed to locate β-catenin. RESULTS: hADMSCs could differentiate toward adipocytes by the adipogenic medium. The results of bioinformatic and dual-luciferase analyses show that TCF-4 is a potential target of miR-26b-5p. The immunofluorescence intensity of TCF4 and β-catenin were inhibited by miR-26b-5p in hADMSCs. Overexpression of miR-26b-5p promotes the adipogenic differentiation of hADMSCs. Overexpression of TCF-4 and β-catenin inhibits the adipogenic differentiation of hADMSCs. The adipogenic differentiation of hADMSCs that promoted by knocking down TCF4 could be weakened by low-expression of miR-26b-5p. The stimulative effect of β-catenin low-expression in adipogenic differentiation was inhibited by miR-26b-5p inhibitor. Conclusions: miR-26b-5p is a negative regulator to inhibit TCF-4 directly, and then inactivated Wnt/β-catenin pathway, which promotes the adipogenic differentiation of hADMSCs in vitro.


2020 ◽  
Author(s):  
Zhen-Xiong Jin ◽  
Xin-Yuan Liao ◽  
Wei-Wei Da ◽  
Yong-Jian Zhao ◽  
Xiao-Feng Li ◽  
...  

Abstract Summary Osthole has potential therapeutic applications due to its antiosteoporotic. Our study suggested that osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential agent to inhibit bone resorption. Introduction Osthole has potential therapeutic applications due to its antiosteoporotic. we performed study to test if OPG is the target gene of osthole-attenuated osteoclastogenesis. Methods In vivo, using 12-month-old male mice to evaluate the effect of osthole on bone mass. In vitro, Bone marrow stem cells (BMSCs) were isolated, extracted from 3-month-old C57BL/6J mice, 3-month-old β-cateninfx/fx mice, or 3-month-old OPG−/− mice and its littermates of OPG+/+ mice. Results we found that osthole significantly increased the gene and protein levels of OPG expression in primary BMSCs dose-dependently. The deletion of the OPG gene did not affect β-catenin expression and the deletion of the β-catenin gene inhibited OPG expression in BMSCs, which indicated that osthole stimulated the expression of OPG through activation of β-catenin signaling. Conclusion Osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential agent to inhibit bone resorption.


2021 ◽  
Author(s):  
Zhen-Xiong Jin ◽  
Xin-Yuan Liao ◽  
Wei-Wei Da ◽  
Yong-Jian Zhao ◽  
Xiao-Feng Li ◽  
...  

Abstract Introduction Osthole has a potential therapeutic application for anti-osteoporosis. The present study verified whether osthole downregulates osteoclastogenesis via targeting OPG. Methods In vivo, 12-month-old male mice were utilized to evaluate the effect of osthole on bone mass. In vitro, bone marrow stem cells (BMSCs) were isolated and extracted from 3-month-old OPG-/- mice and the littermates of OPG+/+ mice. calvaria osteoblasts were extracted from 3-day-old C57BL/6J mice or 3-day-old OPG-/- mice and the littermates of OPG+/+ mice.Results Osthole significantly increased the gene and protein levels of OPG in primary BMSCs in a dose-dependent manner. The deletion of the OPG gene did not affect β-catenin expression. The deletion of the β-catenin gene inhibited OPG expression in BMSCs, indicating that osthole stimulates the expression of OPG via activation of β-catenin signaling.Conclusion Osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential drug for the senile osteoporosis.


Author(s):  
Bruna O. S. Câmara ◽  
Bruno M. Bertassoli ◽  
Natália M. Ocarino ◽  
Rogéria Serakides

The use of stem cells in cell therapies has shown promising results in the treatment of several diseases, including diabetes mellitus, in both humans and animals. Mesenchymal stem cells (MSCs) can be isolated from various locations, including bone marrow, adipose tissues, synovia, muscles, dental pulp, umbilical cords, and the placenta. In vitro, by manipulating the composition of the culture medium or transfection, MSCs can differentiate into several cell lineages, including insulin-producing cells (IPCs). Unlike osteogenic, chondrogenic, and adipogenic differentiation, for which the culture medium and time are similar between studies, studies involving the induction of MSC differentiation in IPCs differ greatly. This divergence is usually evident in relation to the differentiation technique used, the composition of the culture medium, the cultivation time, which can vary from a few hours to several months, and the number of steps to complete differentiation. However, although there is no “gold standard” differentiation medium composition, most prominent studies mention the use of nicotinamide, exedin-4, ß-mercaptoethanol, fibroblast growth factor b (FGFb), and glucose in the culture medium to promote the differentiation of MSCs into IPCs. Therefore, the purpose of this review is to investigate the stages of MSC differentiation into IPCs both in vivo and in vitro, as well as address differentiation techniques and molecular actions and mechanisms by which some substances, such as nicotinamide, exedin-4, ßmercaptoethanol, FGFb, and glucose, participate in the differentiation process.


Author(s):  
Reza Afrisham ◽  
Sahar Sadegh-Nejadi ◽  
Reza Meshkani ◽  
Solaleh Emamgholipour ◽  
Molood Bagherieh ◽  
...  

Introduction: Obesity is a disorder with low-grade chronic inflammation that plays a key role in the hepatic inflammation and steatosis. Moreover, there are studies to support the role of exosomes in the cellular communications, the regulation of metabolic homeostasis and immunomodulatory activity. Accordingly, we aimed to evaluate the influence of plasma circulating exosomes derived from females with normal-weight and obesity on the secretion of inflammatory cytokines in human liver cells. Methods: Plasma circulating exosomes were isolated from four normal (N-Exo) and four obese (O-Exo) women. The exosomes were characterized and approved for CD63 expression (common exosomal protein marker) and morphology/size using the western blot and TEM methods, respectively. The exosomes were used for stimulation of HepG2 cells in vitro. After 24 h incubation, the protein levels of TNF-α,IL-6, and IL-1β were measured in the culture supernatant of HepG2 cells using the ELISA kit. Results: The protein levels of IL-6 and TNF-α in the cells treated with O-Exo and N-Exo reduced significantly in comparison with control group (P=0.039 and P<0.001 respectively), while significance differences were not found between normal and obese groups (P=0.808, and P=0.978 respectively). However, no significant differences were found between three groups in term of IL-1β levels (P=0.069). Based on the correlation analysis, the protein levels of IL-6 were positively correlated with TNF-α (r 0.978, P<0.001). Conclusion: These findings suggest that plasma circulating exosomes have probably anti-inflammatory properties independently from body mass index and may decrease the secretion of inflammatory cytokines in liver. However, further investigations in vitro and in vivo are needed to address the anti-inflammatory function of N-Exo and O-Exo in human liver cells and/or other cells.


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