miR-142a-5p promoted osteoblast differentiation via targeting nuclear factor IA

Aqueous extract of Rehmanniae Radix Praeparata improves bone health in ovariectomized rats by modulating the miR-29a-3p/NFIA/Wnt signaling pathway axis

ETHNOPHARMACOLOGICAL RELEVANCE

Rehmanniae Radix Praeparata (RRP), a widely used traditional Chinese medicine and a processed form of Rehmannia glutinosa, is primarily utilized to supplement kidney function and promote bone health. Clinical evidence suggests that RRP exhibits significant efficacy in the treatment of osteoporosis (OP). However, the precise mechanisms underlying its therapeutic effects remain incompletely understood.

AIM OF THE STUDY

OP is a systemic skeletal disorder characterized by reduced bone density and quality, leading to an increased risk of fractures. The aim of this study is to evaluate the effectiveness and underlying mechanisms of RRP in treating OP.

MATERIALS AND METHODS

Ovariectomized (OVX) rats were administered RRP aqueous extract via gavage for three months. After the treatment period, femoral microstructure and osteogenic protein levels were assessed to evaluate the efficacy of RRP. Serum exosomes (Exos) derived from different groups of rats were isolated and characterized. The levels of miR-29a-3p in serum-derived Exos and femoral tissue were quantified. Subsequently, Exos were co-cultured with rat bone marrow mesenchymal stem cells (rBMSCs) to investigate their role in promoting osteogenic differentiation and explore the molecular mechanisms underlying this process, particularly through the miR-29a-3p/NFIA/Wnt signaling pathway axis.

RESULTS

OVX rats exhibited significant bone microdamage. In contrast, the RRP-treated OVX rats showed marked improvements in femoral bone microstructure and increased osteogenic protein expression. MiR-29a-3p levels were elevated in serum-derived Exos from the RRP-treated rats. Furthermore, rBMSCs treated with these Exos displayed an increase in miR-29a-3p expression. Further investigations revealed that miR-29a-3p promoted osteogenesis by inhibiting NFIA expression in both bone tissue and rBMSCs. Overexpression of NFIA reversed the osteogenic effects of miR-29a-3p, confirming NFIA as its direct target and suggesting that miR-29a-3p enhances osteogenesis by inhibiting NFIA. Additionally, NFIA was found to promote the transcription of SFRP1, an inhibitor of the Wnt signaling pathway. Our findings suggest that the RRP aqueous extract increases miR-29a-3p levels in serum Exos, which in turn inhibits NFIA and activates the Wnt signaling pathway, thereby promoting osteogenesis.

CONCLUSION

These findings suggest that the RRP aqueous extract improves bone health and mitigates bone microstructural damage caused by OP through the regulation of the miR-29a-3p/NFIA/Wnt signaling pathway axis.

Optimized human dedifferentiated fat cells from the buccal fat pad-derived osteoinductive extracellular vesicles promote osteoblast differentiation

Background/purpose

Bone reconstruction in the maxillofacial region typically relies on autologous bone grafting, which presents challenges, including donor site complications and graft limitations. Recent advances in tissue engineering have identified highly pure and proliferative dedifferentiated fat cells (DFATs) as promising alternatives. Herein, we explored the capacity for osteoblast differentiation and the osteoinductive characteristics of extracellular vesicles derived from DFATs (DFAT-EVs).

Materials and methods

DFATs were isolated from human buccal fat pads, cultured to confluency, and placed in either a standard or osteogenic induction medium. After culturing for 3 days, the conditioned medium was used to generate EVs using the size-exclusion chromatography and concentration filter method.

Results

Characterization of DFAT-EVs revealed typical EV morphology and positive markers (CD9 and CD63), with no differences between the two groups. In vitro assays demonstrated that EVs derived from the osteogenic induction medium (OI-EVs) significantly increased alkaline phosphatase activity and osteogenesis-related genes (Runx2 and collagen type I) compared to control EVs. Next-generation sequencing identified differentially expressed miRNAs, and gene ontology analysis suggested pathways involved in osteoblast differentiation.

Conclusion

Isolating DFATs from buccal fat pads under osteogenic induction conditions offers a procedure confined to the oral cavity, eliminating the need for harvesting from other sites. Thus, DFAT-EVs hold promise for promoting bone regeneration in maxillofacial applications.

Genome-wide association study reveals the candidate genes of humerus quality in laying duck

Bone plays a crucial role in poultry's health and production. However, during the selection and cage farming, there has been a decline in bone quality. As the development of breeding theory, researchers find that it's possible to enhance bone quality through selective breeding.This study measure 8 humerus quality in 260 samples of the 350-day-old female duck. By descripting the basic characteristic traits, mechanical property traits we found that all the bone quality traits had a large variable coefficient, especially mechanical properties trait (20-70%), indicating that there was a large difference in bone health status among laying ducks. The phenotypic correlations showed a high correlation between weight and density, diameter and perimeter, breaking and toughness (r = 0.52-0.68). And then, we performed the Genome-wide association study (GWAS) to reveal the candidate genes of humerus quality in ducks. Seven candidate protein-coding genes were identified with perimeter trait, and 52 protein-coding genes were associated with toughness trait. We also analysed the candidate region and performed KEGG and GO analyse for 75 candidate genes. Furthermore, the expression analyse of the above candidate genes in different stage of humerus and different tissues were performed. Finally, AP2A2, SMAD3, SMNDC1, NFIA, EPHB2, PMEPA1, UNC5C, ESR1, VAV3, NFATC2 deserve further focus. The obtained results can contribute to new insight into bone quality and provide new genetic biomarkers for application in duck breeding programs.

MicroRNAs in osteoblast differentiation and fracture healing: From pathogenesis to therapeutic implication

The term "fracture" pertains to the occurrence of bones being either fully or partially disrupted as a result of external forces. Prolonged fracture healing can present a notable danger to the patient's general health and overall quality of life. The significance of osteoblasts in the process of new bone formation is widely recognized, and optimizing their function could be a desirable strategy. Therefore, the mending of bone fractures is intricately linked to the processes of osteogenic differentiation and mineralization. MicroRNAs (miRNAs) are RNA molecules that do not encode for proteins, but rather modulate the functioning of physiological processes by directly targeting proteins. The participation of microRNAs (miRNAs) in experimental investigations has been extensive, and their control functions have earned them the recognition as primary regulators of the human genome. Earlier studies have shown that modulating the expression of miRNAs, either by increasing or decreasing their levels, can initiate the differentiation of osteoblasts. This implies that miRNAs play a pivotal function in promoting osteogenesis, facilitating bone mineralization and formation, ultimately leading to an efficient healing of fractures. Hence, focusing on miRNAs can be considered a propitious therapeutic approach to accelerate the healing of fractures and forestall nonunion. In this manner, the information supplied by this investigation has the potential to aid in upcoming clinical utilization, including its possible use as biomarkers or as resources for devising innovative therapeutic tactics aimed at promoting fracture healing.

Exosomal Osteoclast-Derived miRNA in Rheumatoid Arthritis: From Their Pathogenesis in Bone Erosion to New Therapeutic Approaches

Rheumatoid arthritis (RA) is an autoimmune disease that causes inflammation, pain, and ultimately, bone erosion of the joints. The causes of this disease are multifactorial, including genetic factors, such as the presence of the human leukocyte antigen (HLA)-DRB1*04 variant, alterations in the microbiota, or immune factors including increased cytotoxic T lymphocytes (CTLs), neutrophils, or elevated M1 macrophages which, taken together, produce high levels of pro-inflammatory cytokines. In this review, we focused on the function exerted by osteoclasts on osteoblasts and other osteoclasts by means of the release of exosomal microRNAs (miRNAs). Based on a thorough revision, we classified these molecules into three categories according to their function: osteoclast inhibitors (miR-23a, miR-29b, and miR-214), osteoblast inhibitors (miR-22-3p, miR-26a, miR-27a, miR-29a, miR-125b, and miR-146a), and osteoblast enhancers (miR-20a, miR-34a, miR-96, miR-106a, miR-142, miR-199a, miR-324, and miR-486b). Finally, we analyzed potential therapeutic targets of these exosomal miRNAs, such as the use of antagomiRs, blockmiRs, agomiRs and competitive endogenous RNAs (ceRNAs), which are already being tested in murine and ex vivo models of RA. These strategies might have an important role in reestablishing the regulation of osteoclast and osteoblast differentiation making progress in the development of personalized medicine.

Osteoblast-derived exosomes promote osteogenic differentiation of osteosarcoma cells via URG4/Wnt signaling pathway

Osteosarcoma is a primary malignant bone tumor. Although surgery and chemotherapy are the main treatment methods, the overall curative effect remains unsatisfactory. Therefore, there is an urgent need to develop new therapeutic options for osteosarcoma. In this study, the effect and molecular mechanism of osteoblast-derived exosomes on the treatment of osteosarcoma were evaluated. Human primary osteoblasts were cultured to observe the effects of osteoblast-derived exosomes on the osteogenic differentiation of osteosarcoma cells both in vitro and in vivo. Alizarin red staining and alkaline phosphatase detection were used to evaluate the degree of osteogenic differentiation, and immunofluorescence and Western blotting were used to detect protein expression. The results showed that osteoblast-derived exosomes effectively inhibited the proliferation of osteosarcoma cells and promoted their mineralization in vitro. The exosomes also significantly inhibited tumor growth and promoted tumor tissue mineralization in vivo. Osteoblast-derived exosomes upregulated the expression of bone sialoprotein, osteonectin, osteopontin, runt-related transcription factor 2, and Wnt inhibitory factor 1, downregulated the expression of cyclin D1, and suppressed the nuclear accumulation of β-catenin and promoted its phosphorylation in vitro and in vivo. However, these effects were significantly reversed by upregulated gene (URG) 4 overexpression. These findings suggest that osteoblast-derived exosomes could activate the osteogenic differentiation process in osteosarcoma cells and promote their differentiation by targeting the URG4/Wnt signaling pathway.

miR-142: A Master Regulator in Hematological Malignancies and Therapeutic Opportunities

MicroRNAs (miRNAs) are a type of non-coding RNA whose dysregulation is frequently associated with the onset and progression of human cancers. miR-142, an ultra-conserved miRNA with both active -3p and -5p mature strands and wide-ranging physiological targets, has been the subject of countless studies over the years. Due to its preferential expression in hematopoietic cells, miR-142 has been found to be associated with numerous types of lymphomas and leukemias. This review elucidates the multifaceted role of miR-142 in human physiology, its influence on hematopoiesis and hematopoietic cells, and its intriguing involvement in exosome-mediated miR-142 transport. Moreover, we offer a comprehensive exploration of the genetic and molecular landscape of the miR-142 genomic locus, highlighting its mutations and dysregulation within hematological malignancies. Finally, we discuss potential avenues for harnessing the therapeutic potential of miR-142 in the context of hematological malignancies.

Temporal transcriptome features identify early skeletal commitment during human epiphysis development at single-cell resolution

Human epiphyseal development has been mainly investigated through radiological and histological approaches, uncovering few details of cellular temporal genetic alternations. Using single-cell RNA sequencing, we investigated the dynamic transcriptome changes during post-conception weeks (PCWs) 15-25 of human distal femoral epiphysis cells. We find epiphyseal cells contain multiple subtypes distinguished by specific markers, gene signatures, Gene Ontology (GO) enrichment analysis, and gene set variation analysis (GSVA). We identify the populations committed to cartilage or ossification at this time, although the secondary ossification centers (SOCs) have not formed. We describe the temporal alternation in transcriptional expression utilizing trajectories, transcriptional regulatory networks, and intercellular communication analyses. Moreover, we find the emergence of the ossification-committed population is correlated with the COL2A1-(ITGA2/11+ITGB1) signaling. NOTCH signaling may contribute to the formation of cartilage canals and ossification via NOTCH signaling. Our findings will advance the understanding of single-cell genetic changes underlying fetal epiphysis development.

RNA-Sequence Reveals the Regulatory Mechanism of miR-149 on Osteoblast Skeleton under Mechanical Tension

Objective

Based on RNA-sequencing (RNA-seq), the regulation of miRNAs differentially expressed in dental, periodontal, and alveolar bone tissue of orthodontic tree shrews on osteoblast skeleton under tension was investigated.

Methods

Tree shrews were used to construct orthodontic models. We used RNA-seq to identify differentially expressed miRNAs in periodontal tissues of the treatment group and control group tree shrews. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used for enrichment analysis. Human osteoblast MG63 was treated with 5000 U mechanical tension. Real-time quantitative polymerase chain reaction (RT-qPCR) detected the expression of miR-149 and ARFGAP with SH3 domain, Ankyrin repeat, and Ph domain 3 (ASAP3) mRNA. Western blot detected the protein levels of ASAP3, F-actin, osteogenic markers bone morphogenetic protein 2 (BMP2), and runt-related transcription factor 2 (RUNX2). Rhodamine phalloidin was used to observe the fluorescence intensity of F-actin. Validation of the targeting relationship between miR-149 and ASAP3 by dual luciferase reporter gene assay.

Results

By performing miRNA-seq analysis on the dental and periodontal tissue of tree shrews in the treatment group and control group, we identified 51 upregulated miRNAs and 13 downregulated miRNAs. The expression of miR-149 in the dental and periodontal tissue of tree shrew and MG63 cells treated with mechanical tension was decreased, and miR-149 targeted ASAP3. Knockdown of ASAP3 inhibited the fluorescence intensity of F-actin in MG63 cells treated with 5000 U tension for 36 h, and overexpression of ASAP3 promoted the expression of F-actin and osteogenic markers BMP2 and RUNX2.

Conclusions

These findings revealed that miR-149 could modulate osteoblast differentiation under orthodontics mechanical tension through targeting ASAP3.

LncMIR181A1HG is a novel chromatin-bound epigenetic suppressor of early stage osteogenic lineage commitment

Bone formation requires osteogenic differentiation of multipotent mesenchymal stromal cells (MSCs) and lineage progression of committed osteoblast precursors. Osteogenic phenotype commitment is epigenetically controlled by genomic (chromatin) and non-genomic (non-coding RNA) mechanisms. Control of osteogenesis by long non-coding RNAs remains a largely unexplored molecular frontier. Here, we performed comprehensive transcriptome analysis at early stages of osteogenic cell fate determination in human MSCs, focusing on expression of lncRNAs. We identified a chromatin-bound lncRNA (MIR181A1HG) that is highly expressed in self-renewing MSCs. MIR181A1HG is down-regulated when MSCs become osteogenic lineage committed and is retained during adipogenic differentiation, suggesting lineage-related molecular functions. Consistent with a key role in human MSC proliferation and survival, we demonstrate that knockdown of MIR181A1HG in the absence of osteogenic stimuli impedes cell cycle progression. Loss of MIR181A1HG enhances differentiation into osteo-chondroprogenitors that produce multiple extracellular matrix proteins. RNA-seq analysis shows that loss of chromatin-bound MIR181A1HG alters expression and BMP2 responsiveness of skeletal gene networks (e.g., SOX5 and DLX5). We propose that MIR181A1HG is a novel epigenetic regulator of early stages of mesenchymal lineage commitment towards osteo-chondroprogenitors. This discovery permits consideration of MIR181A1HG and its associated regulatory pathways as targets for promoting new bone formation in skeletal disorders.

MicroRNA-361-5p Aggravates Acute Pancreatitis by Promoting Interleukin-17A Secretion via Impairment of Nuclear Factor IA-Dependent Hes1 Downregulation

This study set out to explore the potential role of microRNA-361-5p (miR-361-5p) in acute pancreatitis through regulation of interleukin-17A (IL-17A). We first identified the expression of miR-361-5p, IL-17A, nuclear factor IA (NFIA), and hes family bHLH transcription factor 1 (Hes1) in serum samples collected from patients with acute pancreatitis, caerulein-induced mice, and a Th17 cell model. The predicted binding of miR-361-5p to NFIA was confirmed in vitro. Gain- and loss-of-function assays of miR-361-5p and NFIA were employed to elucidate their effects on acute pancreatitis. miR-361-5p promoted Th17 cells to secrete IL-17A and then aggravated acute pancreatitis. miR-361-5p directly targeted NFIA by binding to its promoter region, leading to its downregulation. Overexpression of NFIA reduced Hes1 expression and rescued the promoting effect of miR-361-5p on IL-17A secretion. In summary, miR-361-5p enhances IL-17A secretion from Th17 cells and thus aggravates acute pancreatitis by targeting NFIA and upregulating Hes1.

miR-452-3p inhibited osteoblast differentiation by targeting Smad4

Osteoblast differentiation is a complex process that is essential for normal bone formation. A growing number of studies have shown that microRNAs (miRNAs) are key regulators in a variety of physiological and pathological processes, including osteogenesis. In this study, BMP2 was used to induce MC3T3-E1 cells to construct osteoblast differentiation cell model. Then, we investigated the effect of miR-452-3p on osteoblast differentiation and the related molecular mechanism by RT-PCR analysis, Western blot analysis, ALP activity, and Alizarin Red Staining. We found that miR-452-3p was significantly downregulated in osteoblast differentiation. Overexpression miR-452-3p (miR-452-3p mimic) significantly inhibited the expression of osteoblast marker genes RUNX2, osteopontin (OPN), and collagen type 1 a1 chain (Col1A1), and decreased the number of calcium nodules and ALP activity. In contrast, knockdown miR-452-3p (miR-452-3p inhibitor) produced the opposite effect. In terms of mechanism, we found that Smad4 may be the target of miR-452-3p, and knockdown Smad4 (si-Smad4) partially inhibited the osteoblast differentiation enhanced by miR-452-3p. Our results suggested that miR-452-3p plays an important role in osteoblast differentiation by targeting Smad4. Therefore, miR-452-3p is expected to be used in the treatment of bone formation and regeneration.

Multiple targets identified with genome wide profiling of small RNA and mRNA expression are linked to fracture healing in mice

Long-bone fracture is a common injury and its healing process at the fracture site involves several overlapping phases, including inflammation, migration of mesenchymal progenitors into the fracture site, endochondral ossification, angiogenesis and finally bone remodelling. Increasing evidence shows that small noncoding RNAs are important regulators of chondrogenesis, osteogenesis and fracture healing. MicroRNAs are small single-stranded, non-coding RNA-molecules intervening in most physiological and biological processes, including fracture healing. Angiogenin-cleaved 5' tRNA halves, also called as tiRNAs (stress-induced RNAs) have been shown to repress protein translation. In order to gain further understanding on the role of small noncoding RNAs in fracture healing, genome wide expression profiles of tiRNAs, miRNAs and mRNAs were followed up to 14 days after fracture in callus tissue of an in vivo mouse model with closed tibial fracture and, compared to intact bone and articular cartilage at 2 months of age. Total tiRNA expression level in cartilage was only approximately one third of that observed in control D0 bone. In callus tissue, 11 mature 5'end tiRNAs out of 191 tiRNAs were highly expressed, and seven of them were differentially expressed during fracture healing. When comparing the control tissues, 25 miRNAs characteristic to bone and 29 miRNAs characteristic to cartilage tissue homeostasis were identified. Further, a total of 54 out of 806 miRNAs and 5420 out of 18,700 mRNAs were differentially expressed (DE) in callus tissue during fracture healing and, in comparison to control bone. They were associated to gene ontology processes related to mesenchymal tissue development and differentiation. A total of 581 miRNA-mRNA interactions were identified for these 54 DE miRNAs by literature searches in PubMed, thereby linking by Spearman correlation analysis 14 downregulated and 28 upregulated miRNAs to 164 negatively correlating and 168 positively correlating miRNA-mRNA pairs with chondrogenic and osteogenic phases of fracture healing. These data indicated that tiRNAs and miRNAs were differentially expressed in fracture callus tissue, suggesting them important physiological functions during fracture healing. Hence, the data provided by this study may contribute to future clinical applications, such as potential use as biomarkers or as tools in the development of novel therapeutic approaches for fracture healing.