The IRF1/GBP5 axis promotes osteoarthritis progression by activating chondrocyte pyroptosis.

Background: Osteoarthritis (OA) is a chronic degenerative joint disease that primarily affects middle-aged and elderly individuals. The decline in chondrocyte function plays a crucial role in the development of OA. Inflammasome-mediated chondrocyte pyroptosis is implicated in matrix degradation and cartilage degeneration in OA patients. Guanylate binding protein 5 (GBP5), a member of the GTPase family induced by Interferon-γ (IFN-γ), significantly influences cellular inflammatory responses, including intracellular inflammasome activation and cytokine release. However, the role of GBP5 in chondrocyte pyroptosis and OA progression remains unclear. Methods: In this study, we used tumor necrosis factor-α (TNF-α) to induce inflammation and created an OA mouse model with surgically-induced destabilization of the medial meniscus (DMM). We isolated and cultured primary chondrocytes from the knee joints of suckling C57 mice. TNF-α-stimulated primary chondrocytes served as an in vitro model for OA and underwent RNA sequencing. Chondrocytes were transfected with GBP5-overexpression plasmids and small interfering RNA and were subsequently treated with TNF-α. We assessed the expression of cartilage matrix components (COL2A1 and aggrecan), catabolic factors (MMP9 and MMP13), and NLRP3 inflammasome pathway genes (NLRP3, Caspase1, GSDMD, Pro-IL-1ß, and Pro-Caspase1) using RT-qPCR and Western blotting. We analyzed the expression of GBP5, NLRP3, and Caspase1 in the cartilage of DMM-induced post-traumatic OA mice and human OA patients. Immunohistochemistry (IHC) was used to detect the expression of GBP5, NLRP3 and GSDMD in cartilage specimens from OA patients and mouse DMM models. Chondrocyte pyroptosis was assessed using flow cytometry, and the levels of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) were measured with ELISA. We conducted double luciferase reporter gene and chromatin immunoprecipitation (ChIP) assays to confirm the relationship between IRF1 and GBP5. Results: GBP5 expression increased in TNF-α-induced chondrocytes, as revealed by RNA sequencing. GBP5 inhibited COL2A1 and aggrecan expression while promoting the expression of MMP9, MMP13, NLRP3, Caspase1, GSDMD, Pro-IL-1ß, and Pro-Caspase1. GBP5 expression also increased in the cartilage of DMM-induced post-traumatic OA mice and human OA patients. Knockout of GBP5 reduced chondrocyte injury in OA mice. GBP5 promoted chondrocyte pyroptosis and the production of IL-1ß and IL-18. Additionally, we found that IRF1 bound to the promoter region of GBP5, enhancing its expression. After co-transfected with ad-IRF1 and siGBP5, the expression of pyroptosis-related genes was significantly decreased compared with ad-IRF1 group. Conclusions: The IRF1/GBP5 axis enhances extracellular matrix (ECM) degradation and promotes pyroptosis during OA development, through the NLRP3 inflammasome signaling pathway. The translational potential of this article: This study underscores the significance of the IRF1/GBP5 axis in NLRP3 inflammasome-mediated chondrocyte pyroptosis and osteoarthritic chondrocyte injury. Modulating IRF1 and GBP5 expression could serve as a novel therapeutic target for OA.

Antagonizing exosomal miR-18a-5p derived from prostate cancer cells ameliorates metastasis-induced osteoblastic lesions by targeting Hist1h2bc and activating Wnt/ß-catenin pathway.

More than 50% of prostate cancer (PCa) patients have bone metastasis with osteoblastic lesions. MiR-18a-5p is associated with the development and metastasis of PCa, but it remains unclear whether it is involved in osteoblastic lesions. We first found that miR-18a-5p was highly expressed in the bone microenvironment of patients with PCa bone metastases. To address how miR-18a-5p affects PCa osteoblastic lesions, antagonizing miR-18a-5p in PCa cells or pre-osteoblasts inhibited osteoblast differentiation in vitro. Moreover, injection of PCa cells with miR-18a-5p inhibition improved bone biomechanical properties and bone mineral mass in vivo. Furthermore, miR-18a-5p was transferred to osteoblasts by exosomes derived from PCa cells and targeted the Hist1h2bc gene, resulting in Ctnnb1 up-regulation in the Wnt/ß-catenin signaling pathway. Translationally, antagomir-18a-5p significantly improved bone biomechanical properties and alleviated sclerotic lesions from osteoblastic metastases in BALB/c nude mice. These data suggest that inhibition of exosome-delivered miR-18a-5p ameliorates PCa-induced osteoblastic lesions.

A complementary low-Schottky-barrier S/D-based nanoscale dopingless bidirectional reconfigurable field effect transistor with an improved forward current.

In this paper, a nanoscale dopingless bidirectional RFET (BRFET) is proposed. Unlike conventional BRFETs, the proposed BRFET uses two different metal materials to form two different types of Schottky barriers on the interface between the S/D and silicon. For one of the two metal forms, the Schottky barrier height between the conduction band of the semiconductor and one of the two metal materials is lower than half of the energy band gap. The Schottky barrier height between the valence band of the semiconductor and the other kind of the two metal materials is lower than half of the energy band gap of the semiconductor. Therefore, a complementary low Schottky barrier (CLSB) is formed. Therefore, more carriers from the source electrode can easily flow into the semiconductor region through thermionic emission in both n-mode and p-mode compared to conventional BRFET operation, which generates carriers through the band-to-band tunneling effect. Therefore, a larger forward current can be achieved by the proposed CLSB-BRFET. The performance of the CLSB-BRFET is investigated by device simulation and compared with that of the BRFET. The working principle is interpreted through an analysis based on energy band theory. The output characteristics and reconfigurable function are also investigated and verified.

Effect of rapeseed straw-derived biochar on soil bacterial community structure at tillering stage of Oryza Sativa.

Numerous studies have reported the dynamics of microbes when biochar was applied, whereas the information on the alterations of bacterial community after application of rapeseed straw-derived biochar is limited. A pot experiment with two rapeseed straw-derived biochar application treatments (with biochar application at the rate of 200 g/pot, C1, and without biochar application, 0 g/pot, C0) was conducted. No significant differences were observed in the number of operational taxonomic units, observed species, Shannon index, Simpson index, Chao1, ACE, and phylogenetic diversity whole tree between the C1 and C0 treatments. Taxonomic analysis at the phylum level showed that the abundances of Bacteroidetes and Parcubacteria were higher in the C1 treatment compared to the C0 treatment, while Acidobacteria, Chloroflexi, Rokubacteria, Berkelbacteria, and Latescibacteria were observed with higher abundance in the C0 treatment compared to the C1 treatment. Taxonomic analysis at the genus level showed that the abundances of Gracilibacter, Lentimicrobium, unidentified Rikenellaceae, Hydrogenophaga, and Bacillus were higher in the C1 treatment compared to the C0 treatment, while Candidatus Solibacter, Candidatus Koribacter, and Lutispora abundances were found to be higher in the C0 treatment compared to the C1 treatment. Obvious clusters were observed between the C1 and C0 treatments in both principal component analysis and nonmetric multidimensional scaling. These results indicate that soil bacterial community was altered after rapeseed straw-derived biochar was applied.

Long non-coding RNA HCAR promotes endochondral bone repair by upregulating VEGF and MMP13 in hypertrophic chondrocyte through sponging miR-15b-5p.

Endochondral bone formation is an important route for bone repair. Although emerging evidence has revealed the functions of long non-coding RNAs (lncRNAs) in bone and cartilage development, the effect of lncRNAs in endochondral bone repair is still largely unknown. Here, we identified a lncRNA, named Hypertrophic Chondrocyte Angiogenesis-related lncRNA (HCAR), and proved it to promote the endochondral bone repair by upregulating the expression of matrix metallopeptidase 13 (Mmp13) and vascular endothelial growth factor α (Vegfa) in hypertrophic chondrocytes. Lnc-HCAR knockdown in hypertrophic chondrocytes restrained the cartilage matrix remodeling and decrease the CD31hiEmcnhi vessels number in a bone repair model. Mechanistically, we proved that lnc-HCAR was mainly enriched in the cytoplasm using fluorescence in situ hybridization (FISH) assay, and it acted as a molecular sponge for miR-15b-5p. Further, in hypertrophic chondrocytes, lnc-HCAR competitively bound to miR-15b-5p to increase Vegfa and Mmp13 expression. Our results proved that lncRNA is deeply involved in endochondral bone repair, which will provide a new theoretical basis for future strategies for promoting fracture healing.

Angelicin Alleviates Post-Trauma Osteoarthritis Progression by Regulating Macrophage Polarization via STAT3 Signaling Pathway.

Post-trauma osteoarthritis (PTOA) is the most common articular disease characterized by degeneration and destruction of articular cartilage (Bultink and Lems, Curr. Rheumatol Rep., 2013, 15, 328). Inflammatory response of local joint tissue induced by trauma is the most critical factor accelerating osteoarthritis (OA) progression (Sharma et al., 2019; Osteoarthritis. Cartilage, 28, 658-668). M1/M2 macrophages polarization and repolarization participates in local inflammation, which plays a major role in the progression of OA (Zhang et al., 2018; Ann. Rheum. Dis., 77, 1524-1534). The regulating effect of macrophage polarization has been reported as a potential therapy to alleviate OA progression. Synovitis induced by polarized macrophages could profoundly affect the chondrocyte and cartilage matrix (Zhang et al., 2018; Ann. Rheum. Dis., 77, 1524-1534). Generally, anti-inflammatory medications widely used in clinical practice have serious side effects. Therefore, we focus on exploring a new therapeutic strategy with fewer side effects to alleviate the synovitis. Angelicin (ANG) is traditional medicine used in various folk medicine. Previous studies have revealed that angelicin has an inhibitory effect on inflammation (Wei et al., 2016; Inflammation, 39, 1876-1882), tumor growth (Li et al., 2016; Oncology reports, 36, 3,504-3,512; Wang et al., 2017; Molecular Medicine Reports, 16, 5441-5449), DNA damage (Li et al., 2019; Exp. Ther. Med., 18, 1899-1906), and virus proliferation (Li et al., 2018; Front. Cell. Infect. Microbiol., 8, 178). But its specific effects on influencing the process of OA were rarely reported. In this study, the molecular mechanism of angelicin in vivo and in vitro was clearly investigated. Results showed that angelicin could regulate the M1/M2 ratio and function and alleviate the development of PTOA in the meanwhile. Bone marrow monocytes were isolated and induced by macrophage colony-stimulating factor (M-CSF), lipopolysaccharide (LPS) and interferon (IFN)-γ for M1 polarization and interleukin (IL)-4/IL-13 for M2 polarization. Subsequently, repolarization intervention was performed. The results indicate that angelicin can repolarize M1 toward M2 macrophages by upregulating the expression of CD9. Besides, angelicin can also protect and maintain M2 polarization in the presence of LPS/IFN-γ, and subsequently downregulate the expression of inflammatory mediators such as IL-1ß and TNF-α. Mechanistically, angelicin can activate the p-STAT3/STAT3 pathway by conducting CD9/gp130 to repolarize toward M2 macrophages. These results suggest angelicin can alleviate the progression of OA by regulating M1/M2 polarization via the STAT3/p-STAT3 pathway. Therefore, angelicin may have a promising application and potential therapeutic value in OA clinical treatment.

Defective insulin receptor signaling in patients with gestational diabetes is related to dysregulated miR-140 which can be improved by naringenin.

Gestational diabetes (GDM) affects about 20 % of pregnancies globally. Defective insulin receptor (IR) signaling has been found in the placenta from patients with GDM, but the underly mechanism is still unclear. In the present study, the mRNA and protein levels of IR-α, insulin receptor substrate 1(IRS-1) and inulin like growth factor 1 receptor (IGF1R) were detected in the placenta tissue samples from 33 GDM patients and 20 healthy controls. Reduced IR-α protein level was observed in both obese and non-obese GDM patients, and decreased IGF1R protein level was found in obese GDM patients. However, the IR-α and IGF1R mRNAs level was not significantly altered in GDM patients. Subsequently, the expression of 10 miRNAs that have the potential targeting IR-α and IGF1R was examined by qRT-PCR in the placenta, and miR-140-3p was found overexpressed. Through dual-luciferase assay and immunoblotting, miR-140-3p was confirmed to suppress IR-α and IGF1R expression via targeting the 3'UTRs. As a treatment candidate, naringenin downregulated miR-140-3p level in trophoblasts and endothelial cells. Meanwhile, IR-α and IGF1R expression was upregulated by naringenin, and the glucose uptake was increased in naringenin treated trophoblasts and endothelial cells. Finally, naringenin upregulated cell viability, migration capacity of HTR-8/SVneo and HUVEC cells, and increased HUVEC cells angiogenesis in high glucose condition. In conclusion, miR-140-3p overexpression contributes to the defective placental IR signaling in patients with GDM. Naringenin treatment protects trophoblasts and endothelial cells from the harmful high glucose environment which have the potential for GDM treatment.

Engineered scaffolds based on mesenchymal stem cells/preosteoclasts extracellular matrix promote bone regeneration.

Recently, extracellular matrix-based tissue-engineered bone is a promising approach to repairing bone defects, and the seed cells are mostly mesenchymal stem cells. However, bone remodelling is a complex biological process, in which osteoclasts perform bone resorption and osteoblasts dominate bone formation. The interaction and coupling of these two kinds of cells is the key to bone repair. Therefore, the extracellular matrix secreted by the mesenchymal stem cells alone cannot mimic a complex bone regeneration microenvironment, and the addition of extracellular matrix by preosteoclasts may contribute as an effective strategy for bone regeneration. Here, we established the mesenchymal stem cell/preosteoclast extracellular matrix -based tissue-engineered bones and demonstrated that engineered-scaffolds based on mesenchymal stem cell/ preosteoclast extracellular matrix significantly enhanced osteogenesis in a 3 mm rat femur defect model compared with mesenchymal stem cell alone. The bioactive proteins released from the mesenchymal stem cell/ preosteoclast extracellular matrix based tissue-engineered bones also promoted the migration, adhesion, and osteogenic differentiation of mesenchymal stem cells in vitro. As for the mechanisms, the iTRAQ-labeled mass spectrometry was performed, and 608 differentially expressed proteins were found, including the IGFBP5 and CXCL12. Through in vitro studies, we proved that CXCL12 and IGFBP5 proteins, mainly released from the preosteoclasts, contributed to mesenchymal stem cells migration and osteogenic differentiation, respectively. Overall, our research, for the first time, introduce pre-osteoclast into the tissue engineering of bone and optimize the strategy of constructing extracellular matrix-based tissue-engineered bone using different cells to simulate the natural bone regeneration environment, which provides new sight for bone tissue engineering.

Taurine attenuates liver autophagy and injury of offspring in gestational diabetic mellitus rats.

PURPOSE: Gestational diabetes mellitus (GDM) has many adverse effects on offspring, such as abnormal glycolipid metabolism, obesity, insulin resistance, mental retardation, schizophrenia and so on. METHODS: We established a GDM rat model by injecting 1% streptozotocin associated with a high-fat diet one week before pregnancy, and offspring rats were sacrificed at 8 weeks of age to obtain liver tissue for study. We used hematoxylin-eosin (HE) staining to observe liver morphological changes, Tunel staining for hepatocyte apoptosis, transmission electron microscope for liver ultrastructure, and western blot for protein expression in liver tissue. RESULTS: Compared with normal offspring rats, hepatocytes of GDM offspring rats showed obvious edema, liver organ index increased, and hepatocyte apoptosis and autophagosome in the liver were significantly increased; Bax, cleaved-caspase3/caspase3, LCII, Beclin 1, P-IKBα/IKBα and P-p65/p6 protein expression in the liver were significantly increased; Bcl2, p62 and PPARγ protein expression in the liver were significantly decreased. Tau prevented the GDM-related effects in the offspring: Tau decreased hepatocyte edema (or even disappears), liver organ index, hepatocyte apoptosis and the number of autophagosomes in the liver. In addition, Tau also decreased Bax, cleaved-caspase3/caspase3, LCII, Beclin 1, P-IKBα/IKBα and P-p65/p6 protein expression, and increased Bcl2, p62 and PPARγ protein expression in the liver of GDM offspring rats. CONCLUSION: Taurine should be considered as a potential gestational nutritional supplement to prevent liver damage in GDM offspring.

The Renoprotective Effects of Naringenin (NGN) in Gestational Pregnancy.

INTRODUCTION: Gestational diabetes mellitus (GDM) is defined as glucose intolerance that is first diagnosed during pregnancy, a condition risking the health of both the mother and the baby. Naringenin (NGN) has been demonstrated to have multiple therapeutic functions, while it is also considered to exhibit antidiabetic properties. The present study aimed to investigate the protective effects of NGN in pregnant diabetic rats. METHODS: GDM was induced by feeding the rats with a high-fat diet for 5 weeks, followed by intraperitoneal injection of streptozotocin (35 mg/kg). The fasting blood glucose were determined with a glucometer and the 24-h urine protein (24-UPro) were determined by the sulfonyl salicylic acid method. The pathological morphological changes and apoptosis of glomeruli cells of kidney tissue using hematoxylin and eosin (H&E) staining and TUNEL analysis. Enzyme-linked immunosorbent assay (ELISA) kits were used to detect the serum T-AOC, the activity of SOD, the levels of GSH-Px, CAT and MDA, TNF-α, IL-6, TGF-ß, ICAM-1.The expression of related genes were measured by RT-qPCR and Western blot analyses. RESULTS: In the NGN-treated group, it was observed that the general status of the rats was improved, while the levels of blood glucose and 24-UPro were significantly decreased. In addition, the histopathological changes in renal tissues and renal cell apoptosis were significantly improved upon treatment with NGN. The expression levels of oxidative stress and inflammation-associated factors also differed signifigcantly between the model and NGN-treated groups. Upon treatment with NGN, the levels of peroxisome proliferator-activated receptor α were significantly increased, while the activity of enzymes involved in the oxidative metabolism of fatty acids was significantly decreased. CONCLUSION: These preliminary experimental findings demonstrate that NGN has a certain renoprotective effect on GDM, which provides a novel therapeutic option for this condition.

Amino acid content in rice grains is affected by high temperature during the early grain-filling period.

Amino acid content in grains is an important nutritional quality trait in rice. High temperature can affect rice quality by accelerating grain filling. However, there is limited information available on the influence of high temperature on amino acid content in rice grains, especially under natural conditions. In this study, grain-filling traits and amino acid content in the grain of two rice cultivars (Luliangyou 996 and Lingliangyou 268) were compared between two years (2016 and 2017) with contrasting temperatures during the early grain-filling period under field conditions. Average daily mean temperature during the period of 0-5 days after full heading in 2016 (30.1 °C) was 5.4 °C higher than that in 2017. Initial, maximum, and mean grain-filling rates were 42-307% higher in 2016 than in 2017 for Luliangyou 996 and Lingliangyou 268. The time taken to reach the maximum grain-filling rate and active grain-filling duration were 6.3-10.7 d shorter in 2016 compared to 2017 for Luliangyou 996 and Lingliangyou 268. Grain weight was equal to or significantly higher in 2016 than in 2017 for Luliangyou 996 and Lingliangyou 268. N accumulation and N content in the grain were significantly lower in 2016 than in 2017 for both cultivars. The grain contents of all detected amino acids, except for methionine in Luliangyou 996, were significantly lower in 2016 than in 2017. Our study suggests that high temperature during the early grain-filling period can result in an accelerated grain-filling process, reduced N accumulation and content in rice grains, and consequently reduced amino acid content in the grain.

Ceria nanoparticles enhance endochondral ossification-based critical-sized bone defect regeneration by promoting the hypertrophic differentiation of BMSCs via DHX15 activation.

Central ischemic necrosis is one of the biggest obstacles in the clinical application of traditional tissue-engineered bone (TEB) in critical-sized bone defect regeneration. Because of its ability to promote vascular invasion, endochondral ossification-based TEB has been applied for bone defect regeneration. However, inadequate chondrocyte hypertrophy can hinder vascular invasion and matrix mineralization during endochondral ossification. In light of recent studies suggesting that ceria nanoparticles (CNPs) improve the blood vessel distribution within TEB, we modified TEB scaffold surfaces with CNPs and investigated the effect and mechanism of CNPs on endochondral ossification-based bone regeneration. The CNPs used in this study were synthesized by the microemulsion method and modified with alendronate-anchored polyethylene glycol 600. We showed that CNPs accelerated new bone formation and enhanced endochondral ossification-based bone regeneration in both a subcutaneous ectopic osteogenesis model and a mouse model of critical-sized bone defects. Mechanistically, CNPs significantly promoted endochondral ossification-based bone regeneration by ensuring sufficient hypertrophic differentiation via the activation of the RNA helicase, DEAH (Asp-Glu-Ala-His) box helicase 15, and its downstream target, p38 MAPK. These results suggested that CNPs could be applied as a biomaterial to improve the efficacy of endochondral ossification-based bone regeneration in critical-sized bone defects.-Li, J., Kang, F., Gong, X., Bai, Y., Dai, J., Zhao, C., Dou, C., Cao, Z., Liang, M., Dong, R., Jiang, H., Yang, X., Dong, S. Ceria nanoparticles enhance endochondral ossification-based critical-sized bone defect regeneration by promoting the hypertrophic differentiation of BMSCs via DHX15 activation.

MicroRNA-29b regulates hypertrophy of murine mesenchymal stem cells induced toward chondrogenesis.

OBJECTIVE: Chondrocyte hypertrophy, a terminal stage of chondrocyte differentiation, is essential to the endochondral bone formation and is one of the major pathological factors in osteoarthritis. This study investigated the role of microRNA-29b (miR-29b), which is involved in chondrogenesis, in the regulation of hypertrophy in chondrocytes. METHODS: miR-29b expression was assessed during murine mesenchymal stem cells (mMSCs) chondrogenesis. To detect whether miR-29b affects chondrocyte hypertrophy, the mMSCs induced toward chondrogenesis were transfected with miR-29b or its antisense inhibitor (antagomiR-29b). Finally, the differential effects of antagomiR-29b on chondrocytes at different differentiation stages were evaluated by loss-of-function experiments. RESULTS: miR-29b expression was low-level during the early chondrogenic differentiation, however, it was changed to high level during hypertrophy. Subsequently, the gain-of-function and loss-of-function experiments had confirmed that miR-29b promoted hypertrophy in mMSC-derived chondrocytes. In addition, we confirmed that on day 7, when cells were treated with antagomiR-29b, was the optimal intervention time for preventing hypertrophic phenotype of mMSCs in vitro. CONCLUSION: miR-29b regulated chondrogenesis homeostasis and enhance hypertrophic phenotype. These data suggest that miR-29b is a key regulator of the chondrocyte phenotype derived from mMSCs and it might be a potential target for articular cartilage repair.

LncRNA AK077216 promotes RANKL-induced osteoclastogenesis and bone resorption via NFATc1 by inhibition of NIP45.

Osteoclasts derived from the monocyte/macrophage hematopoietic lineage regulate bone resorption, a process balanced by bone formation in the continual renewal of the skeletal system. As dysfunctions of these cells result in bone metabolic diseases such as osteoporosis and osteopetrosis, the exploration of the mechanisms regulating their differentiation is a priority. A potential mechanism may involve long noncoding RNAs (lncRNAs), which are known to regulate various cell biology activities, including proliferation, differentiation, and apoptosis. The expression of the lncRNA AK077216 (Lnc-AK077216) is significantly upregulated during osteoclastogenesis identified by microarray and verified by qPCR. Up- and downregulation of Lnc-AK077216, respectively promotes and inhibits osteoclast differentiation, bone resorption, and the expression of related genes on the basis of tartrate-resistant acid phosphatase staining, qPCR, and western blot results. In addition, Lnc-AK077216 suppresses NIP45 expression and promotes the expression of NFATc1, an essential transcription factor during osteoclastogenesis. Besides, it was found that the expression of Lnc-AK077216 and Nfatc1 is upregulated, whereas Nip45 expression is downregulated in bone marrow and spleen tissues of ovariectomized mice. The results suggest that Lnc-AK077216 regulates NFATc1 expression and promotes osteoclast formation and function, providing a novel mechanism of osteoclastogenesis and a potential biomarker or a new drug target for osteoporosis.

Chemical Self-Assembly of Multifunctional Hydroxyapatite with a Coral-like Nanostructure for Osteoporotic Bone Reconstruction.

Bone defects/fractures are common in older people suffering from osteoporosis. Traditional hydroxyapatite (HA) materials for osteoporotic bone repair face many challenges, including limited bone formation and aseptic loosening of orthopedic implants. In this study, a new multifunctional HA is synthesized by spontaneous assembly of alendronate (AL) and Fe3O4 onto HA nanocrystals for osteoporotic bone regeneration. The chemical coordination of AL and Fe3O4 with HA does not induce lattice deformation, resulting in a functionalized HA (Func-HA) with proper magnetic property and controlled release manner. The Func-HA nanocrystals have been encapsulated in polymer substrates to further investigate their osteogenic capability. In vitro and in vivo evaluations reveal that both AL and Fe3O4, especially the combination of two functional groups on HA, can inhibit osteoclastic activity and promote osteoblast proliferation and differentiation, as well as enhance implant osseointegration and accelerate bone remodeling under osteoporotic condition. The as-developed Func-HA with coordinating antiresorptive ability, magnetic property, and osteoconductivity might be a desirable biomaterial for osteoporotic bone defect/fracture treatment.

Yield effect of applying earthworm castings produced during the oilseed rape-growing season in rice-oilseed rape cropping fields to rice.

In-field earthworm density can be increased by planting oilseed rape during the non-rice growing season as compared to maintaining the rice-growing fields in fallow. This study was conducted to determine the effect on rice yield of earthworm castings produced during the oilseed rape-growing season in rice-oilseed rape cropping fields and to identify the critical factors that contribute to the yield effect. Field microplot experiments were conducted in 2016 and 2017. In 2016, a rice cultivar was grown under a factorial combination of absence (EC0: 0 kg m-2) and presence of earthworm castings (EC1: 17 kg m-2) with three N application rates (9, 12 and 15 g m-2). In 2017, nine rice cultivars were grown under EC0 and EC1 with the moderate N rate as was used in 2016. Results showed that application of earthworm castings produced during the oilseed rape-growing season in rice-oilseed rape cropping fields had a significant positive yield effect on rice. This was attributed to increased panicle m-2 and total aboveground biomass while spikelets panicle-1, spikelet filling percentage, grain weight, and harvest index were not affected. Our study indirectly provides a new evidence that oilseed rape is an excellent previous crop for cereals.

Mangiferin enhances endochondral ossification-based bone repair in massive bone defect by inducing autophagy through activating AMP-activated protein kinase signaling pathway.

Endochondral ossification is crucial for bone formation in both adult bone repair process and embryo long-bone development. In endochondral ossification, bone marrow-derived mesenchymal stem cells (BMSCs) first differentiate to chondrocytes, then BMSC-derived chondrocytes endure a hypertrophic process to generate new bone. Endochondral ossification-based bone repair is a promising strategy to cure massive bone defect, which is a major clinical issue in orthopedics. However, challenges still remain for this novel strategy. One challenge is to ensure the sufficient hypertrophic differentiation. Another is to maintain the survival of the above hypertrophic chondrocytes under the hypoxic environment of massive bone defect. To solve this issue, mangiferin (MAG) was introduced to endochondral ossification-based bone repair. In this report, we proved MAG to be a novel autophagy inducer, which promoted BMSC-derived hypertrophic chondrocyte survival against hypoxia-induced injury through inducing autophagy. Furthermore, MAG enhances hypertrophic differentiation of BMSC-derived chondrocytes via upregulating key hypertrophic markers. Mechanistically, MAG induced autophagy in BMSC-derived chondrocytes by promoting AMPKα phosphorylation. Additionally, MAG balanced the expression of sex-determining region Y-box 9 and runt-related transcription factor 2 to facilitate hypertrophic differentiation. These results indicated that MAG was a potential drug to improve the efficacy of endochondral ossification-based bone repair in massive bone defects.-Bai, Y., Liu, C., Fu, L., Gong, X., Dou, C., Cao, Z., Quan, H., Li, J., Kang, F., Dai, J., Zhao, C., Dong, S. Mangiferin enhances endochondral ossification-based bone repair in massive bone defect by inducing autophagy through activating AMP-activated protein kinase signaling pathway.

Estrogen Deficiency-Mediated M2 Macrophage Osteoclastogenesis Contributes to M1/M2 Ratio Alteration in Ovariectomized Osteoporotic Mice.

In this study, for the first time we discovered that the M1/M2 macrophage phenotype ratio is increased in bone marrow of ovariectomized (OVX) osteoporotic C57BL/6 mice. Considering estrogen is the main variable, we assumed that estrogen participated in this alteration. To determine whether and how estrogen contributes to the change of the M1/M2 ratio, we first isolated bone marrow macrophages (BMMs) from mice femur and stimulated the cells with lipopolysaccharide (LPS)/interferon γ (IFN-γ) for M1 polarization and interleukin 4 (IL-4)/IL-13 for M2 polarization. M1 and M2 macrophages were then exposed to RANKL stimulation, we found that M2 macrophage but not M1 macrophage differentiated into functional osteoclast leading to increased M1/M2 ratio. Intriguingly, 17ß-estradiol (E2) pretreatment prevented osteoclastogenesis from M2 macrophages. By constructing shRNA lentivirus interfering the expression of different estrogen receptors in M2 macrophages, we found that estrogen protects M2 macrophage from receptor activator of nuclear factor κB ligand (RANKL) stimulation selectively through estrogen receptor α (ERα) and the downstream blockage of NF-κB p65 nuclear translocation. Animal studies showed that ERα selective agonist 4,4',4″-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol (PPT) was able to replicate the therapeutic effects of E2 in treating osteoporotic OVX mice. Together, our findings reveal that estrogen deficiency-mediated M2 macrophage osteoclastogenesis leads to increased M1/M2 ratio in OVX mice. Reducing the M1/M2 ratio is a potential therapeutic target in treating postmenopausal osteoporosis. © 2017 American Society for Bone and Mineral Research.