Increased levels of villus-derived exosomal miR-29a-3p in normal pregnancy than uRPL patients suppresses decidual NK cell production of interferon-γ and exerts a therapeutic effect in abortion-prone mice.

OBJECTIVE: Recurrent pregnancy loss (RPL) patients have higher absolute numbers of decidual natural killer (dNK) cells with elevated intracellular IFN-γ levels leading to a pro-inflammatory cytokine milieu, which contributes to RPL pathogenesis. The main objective of this study was twofold: first to explore the regulatory effects and mechanisms of villus-derived exosomes (vEXOs) from induced abortion patients or RPL patients at the level of intracellular IFN-γ in dNK cells; second to determine the validity of application of vEXOs in the treatment of unexplained RPL (uRPL) through in vitro experiments and mouse models. METHODS: Exosomes were isolated from villus explants by ultracentrifugation, co-cultured with dNK cells, and purified by enzymatic digestion and magnetically activated cell sorting. Flow cytometry, enzyme-linked immunosorbent assays, and RT-qPCR were used to determine IFN-γ levels. Comparative miRNA analysis of vEXOs from induced abortion (IA) and uRPL patients was used to screen potential candidates involved in dNK regulation, which was further confirmed by luciferase reporter assays. IA-vEXOs were electroporated with therapeutic miRNAs and encapsulated in a China Food and Drug Administration (CFDA)-approved hyaluronate gel (HA-Gel), which has been used as a clinical biomaterial in cell therapy for > 30 years. In vivo tracking was performed using 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyaine iodide (DiR) labelling. Tail-vein and uterine horn injections were used to evaluate therapeutic effects of the engineered exosomes in an abortion-prone mouse model (CBA/J × DBA/2 J). Placental growth was evaluated based on placental weight. IFN-γ mRNA levels in mouse placentas were measured by RT-qPCR. RESULTS: IFN-γ levels were significantly higher in dNK cells of uRPL patients than in IA patients. Both uRPL-vEXOs and IA-vEXOs could be efficiently internalized by dNK cells, whereas uRPL-vEXOs could not reduce the expression of IFN-γ by dNK cells as much as IA-vEXOs. Mechanistically, miR-29a-3p was delivered by vEXOs to inhibit IFN-γ production by binding to the 3' UTR of IFN-γ mRNA in dNK cells. For in vivo treatment, application of the HA-Gel effectively prolonged the residence time of vEXOs in the uterine cavity via sustained release. Engineered vEXOs loaded with miR-29a-3p reduced the embryo resorption rate in RPL mice with no signs of systemic toxicity. CONCLUSION: Our study provides the first evidence that villi can regulate dNK cell production of IFN-γ via exosome-mediated transfer of miR-29a-3p, which deepens our understanding of maternal-fetal immune tolerance for pregnancy maintenance. Based on this, we developed a new strategy to mix engineered vEXOs with HA-Gel, which exhibited good therapeutic effects in mice with uRPL and could be used for potential clinical applications in uRPL treatment.

TSG6-Exo@CS/GP Attenuates Endometrium Fibrosis by Inhibiting Macrophage Activation in a Murine IUA Model.

Intrauterine adhesion (IUA) is characterized by the formation of fibrous scar tissue within the uterine cavity, which significantly impacts female reproductive health and even leads to infertility. Unfortunately, severe cases of IUA currently lack effective treatments. This study presents a novel approach that utilizes tumor necrosis factor-(TNF) stimulated gene 6 (TSG6)-modified exosomes (Exos) in conjunction with an injectable thermosensitive hydrogel (CS/GP) to mitigate the occurrence of IUA by reducing endometrium fibrosis in a mouse IUA model. This study demonstrate that TSG6-modified Exos effectively inhibits the activation of inflammatory M1-like macrophages during the initial stages of inflammation and maintains the balance of macrophage phenotypes (M1/M2) during the repair phase. Moreover, TSG6 inhibits the interaction between macrophages and endometrial stromal fibroblasts, thereby preventing the activation of stromal fibroblasts into myofibroblasts. Furthermore, this research indicates that CS/GP facilitates the sustained release of TSG6-modified Exos, leading to a significant reduction in both the manifestations of IUA and the extent of endometrium fibrosis. Collectively, through the successful construction of CS/GP loaded with TSG6-modified Exos, a reduction in the occurrence and progression of IUA is achieved by mitigating endometrium fibrosis. Consequently, this approach holds promise for the treatment of IUA.

High estrogen during ovarian stimulation induced loss of maternal imprinted methylation that is essential for placental development via overexpression of TET2 in mouse oocytes.

BACKGROUND: Ovarian stimulation (OS) during assisted reproductive technology (ART) appears to be an independent factor influencing the risk of low birth weight (LBW). Previous studies identified the association between LBW and placenta deterioration, potentially resulting from disturbed genomic DNA methylation in oocytes caused by OS. However, the mechanisms by which OS leads to aberrant DNA methylation patterns in oocytes remains unclear. METHODS: Mouse oocytes and mouse parthenogenetic embryonic stem cells (pESCs) were used to investigate the roles of OS in oocyte DNA methylation. Global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) levels were evaluated using immunofluorescence or colorimetry. Genome-wide DNA methylation was quantified using an Agilent SureSelectXT mouse Methyl-Seq. The DNA methylation status of mesoderm-specific transcript homologue (Mest) promoter region was analyzed using bisulfite sequencing polymerase chain reaction (BSP). The regulatory network between estrogen receptor alpha (ERα, ESR1) and DNA methylation status of Mest promoter region was further detected following the knockdown of ERα or ten-eleven translocation 2 (Tet2). RESULTS: OS resulted in a significant decrease in global 5mC levels and an increase in global 5hmC levels in oocytes. Further investigation revealed that supraphysiological ß-estradiol (E2) during OS induced a notable decrease in DNA 5mC and an increase in 5hmC in both oocytes and pESCs of mice, whereas inhibition of estrogen signaling abolished such induction. Moreover, Tet2 may be a direct transcriptional target gene of ERα, and through the ERα-TET2 axis, supraphysiological E2 resulted in the reduced global levels of DNA 5mC. Furthermore, we identified that MEST, a maternal imprinted gene essential for placental development, lost its imprinted methylation in parthenogenetic placentas originating from OS, and ERα and TET2 combined together to form a protein complex that may promote Mest demethylation. CONCLUSIONS: In this study, a possible mechanism of loss of DNA methylation in oocyte caused by OS was revealed, which may help increase safety and reduce epigenetic abnormalities in ART procedures.

Prodrug-based nanomedicines for rheumatoid arthritis.

Most antirheumatic drugs with high toxicity exhibit a narrow therapeutic window due to their nonspecific distribution in the body, leading to undesirable side effects and reduced patient compliance. To in response to these challenges, prodrug-based nanoparticulate drug delivery systems (PNDDS), which combines prodrug strategy and nanotechnology into a single system, resulting their many advantages, including stability for prodrug structure, the higher drug loading capacity of the system, improving the target activity and bioavailability, and reducing their untoward effects. PNDDS have gained attention as a method for relieving arthralgia syndrome of rheumatoid arthritis in recent years. This article systematically reviews prodrug-based nanocarriers for rheumatism treatment, including Nano systems based on prodrug-encapsulated nanomedicines and conjugate-based nanomedicines. It provides a new direction for the clinical treatment of rheumatoid arthritis.

Alpha-lipoic Acid Prevents Bone Loss in Type 2 Diabetes and Postmenopausal Osteoporosis Coexisting Conditions by Modulating the YAP/Glut4 Pathway.

This study aims to characterize the bone-protecting effects of Alpha-lipoic acid (ALA), a potent antioxidant, against the detrimental effects of the coexistence of type 2 diabetes mellitus (T2DM) and postmenopausal osteoporosis (POP) and identify the possible mechanisms with particular reference to its modulation of YAP/Glut4 pathway. The T2DM and POP coexisting model was induced in mice by high fat diet (HFD) + Streptozocin (STZ) + ovariectomy (OVX). The mice in the treatment groups were given ALA for 10 weeks. In the in vitro study, MC3T3-E1 cells were induced with 500 µM methylglyoxal for 24 h with or without pretreatment with ALA for 24 h. The oxidative and antioxidative biomarkers, bone microarchitecture, histo-morphology, and related protein expression of apoptosis, osteogenic differentiation and the YAP/Glut4 pathway were detected. The results showed ALA could improve glucose tolerance, inhibit oxidative stress and apoptosis and alleviate bone loss. Further study by siRNA technology revealed that the YAP/Glut4 pathway was implicated in the pathogenesis of bone loss due to the coexistence of T2DM and POP. Taken together, the present study has demonstrated for the first time that ALA exerts potent protective effects against bone loss in T2DM and POP coexisting conditions by modulating the YAP/Glut4 pathway.

Coenzyme Q10 Protects Against Hyperlipidemia-Induced Osteoporosis by Improving Mitochondrial Function via Modulating miR-130b-3p/PGC-1α Pathway.

In hyperlipidemia-induced osteoporosis, bone marrow mesenchymal stem cells (BMSCs) differentiate into more adipocytes than osteoblasts, leading to decreased bone formation. It is vital to elucidate the effects of hyperlipidemia on bone metabolism and seek new agents that regulate adipocyte-osteoblast lineage allocation. CoQ10, a rate-limiting coenzyme of the mitochondrial respiratory chain, has been reported to decrease oxidative stress and lipid peroxidation by functioning as a mitochondrial antioxidant. However, its effect on hyperlipidemia-induced osteoporosis remains unknown. Here, we analyzed the therapeutic mechanisms of CoQ10 on hyperlipidemia-induced osteoporosis by using high-fat diet (HFD)-treated ApoE-/- mice or oxidized low-density lipoprotein (ox-LDL)-treated BMSCs. The serum lipid levels were elevated and bone formation-related markers were decreased in HFD-treated ApoE-/- mice and ox-LDL-treated BMSCs, which could be reversed by CoQ10. Additionally, PGC-1α protein expression was decreased in HFD-treated ApoE-/- mice and ox-LDL-treated BMSCs, accompanied by mitochondrial dysfunction, decreased ATP content and overgeneration of reactive oxygen species (ROS), which could also be antagonized by CoQ10. Furthermore, PGC-1α knockdown in vitro promoted ROS generation, BMSC apoptosis, and adipogenic differentiation while attenuating osteogenic differentiation in BMSCs. Mechanistically, it suggested that the expression of PGC1-α protein was increased with miR-130b-3p inhibitor treatment in osteoporosis under hyperlipidemia conditions to improve mitochondrial function. Collectively, CoQ10 alleviates hyperlipidemia-induced osteoporosis in ApoE-/- mice and regulates adipocyte-osteoblast lineage allocation. The possible underlying mechanism may involve the improvement of mitochondrial function by modulating the miR-130b-3p/PGC-1α pathway.

Identifying a panel of nine genes as novel specific model in endometriosis noninvasive diagnosis.

OBJECTIVE: To study biomarkers to develop a novel diagnosis model for endometriosis and validate it using clinical samples. DESIGN: We used publicly available data sets and weighted gene coexpression network analysis to identify differentially expressed genes. Ten machine learning algorithms were used to develop an integrative model for predicting endometriosis. The accuracy and robustness of the model were validated using data sets and clinical samples. SETTING: Department of Obstetrics and Gynecology, Tangdu Hospital, Air Force Medical University, Xi'an, Shaanxi, China. PATIENT(S): The study included clinical patients between the ages of 20 and 40 years who required laparoscopic surgery and who had not undergone hormone therapy within the previous 3 months. All the healthy individuals had given birth to a child at least once in their lives. Patients with inflammatory conditions, malignant diseases, immune diseases, myoma, or adenomyosis were excluded. Paraffin blocks of the samples were collected (case, n = 5; control, n = 5). Blood samples of 58 individuals were collected (case, n = 28; control, n = 30). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The areas under the receiver operator characteristic curve of our diagnostic model were measured for data sets and clinical samples. Multiplex immunohistochemical staining and real-time quantitative polymerase chain reaction assays were used for the validation of the model from tissue slides and peripheral blood samples. RESULT(S): A nine-gene panel endometriosis messenger RNA score (EMScore), was constructed to distinguish the patients with endometriosis from healthy individuals using algorithms. The EMScore accurately predicted endometriosis, and the areas under the receiver operator characteristic curve of our diagnostic model were 0.920, and 0.942 for tissue and blood samples, respectively. Moreover, the EMScore outperformed other acknowledged signatures for predicting endometriosis across seven clinical cohorts. Overall, the EMScore constitutes a sensitive and specific noninvasive diagnostic method for endometriosis. CONCLUSION(S): We developed the EMScore, a novel model that can aid in the diagnosis of endometriosis using peripheral blood samples. This study will contribute to the development of improved clinical noninvasive and sensitive diagnostic tools for endometriosis. These nine genes might be potential target molecules for treating endometriosis.

Bio-inspired nacre-like zirconia/PMMA composites for chairside CAD/CAM dental restorations.

OBJECTIVES: To introduce a versatile fabrication process to fabricate zirconia/PMMA composites for chairside CAD/CAM dental restorations. These zirconia composites have nacre-like lamellar microstructures, competent and tooth-matched mechanical properties, as well as crack resistance behaviours. METHODS: Bi-directional freeze casting was used to fabricate ceramic green bodies with highly aligned lamellar structure. Pressure was then applied to control the ceramic volume fraction. PMMA was infiltrated into the ceramic scaffold. Mechanical tests including 3-point bending, Vickers hardness, and fracture toughness were performed on the composites. The machinability of the composites was also characterised. RESULTS: Two types of nacre-like zirconia/PMMA composites, i.e., 3Y-YZP/PMMA and 5Y-PSZ/PMMA composites were fabricated. The microstructure created was similar to the 'brick and mortar' structure of nacre. Excellent flexural strength (up to 400 MPa and 290 MPa for 3Y-TZP/PMMA and 5Y-PSZ/PMMA composite, respectively), tuneable hardness and elastic modulus within the range similar to enamel, along with improved crack-resistance behaviour were demonstrated on both zirconia composites. In addition, both zirconia/PMMA composites showed acceptable machinability, being easy to mill, as would be required to produce a dental crown. SIGNIFICANCE: Nacre-like zirconia/PMMA composites therefore exhibit the potential for use in the production of chairside CAD/CAM dental restorations.

Epigenetic modification of TWIST1 in macrophages promotes hypertension-induced atherosclerotic plaque instability.

It is accepted that hypertension is a major, independent risk factor for atherosclerotic cardiovascular ischemic events, which are mainly attributed to the formation of unstable, vulnerable atherosclerotic lesions. But the mechanisms by which hypertension aggravates atherosclerosis (AS) through increased macrophage recruitment are unknown. It has been reported that TWIST1 can regulate the shear stress of blood flow in endothelial cells to promote the development of atherosclerosis, but the function of TWIST1 in macrophage recruitment during hypertension remains undefined. Here, the roles of TWIST1 in macrophage activation during N w -nitro-l-arginine-methyl ester (L-NAME; NO-synthase (NOS) inhibitor)-induced hypertension were investigated in ApoE-/- mice fed a high-fat diet (HFD) and RAW264.7 cells treated with oxidized low-density lipoprotein(ox-LDL). Oil Red O staining and hematoxylin and eosin staining were adopted to analyze atherosclerotic lesions and plaque instability. Chromatin immunoprecipitation (ChIP)-PCR was used to explore whether Lysine-specific histone demethylase 1A (LSD1/KDM1A) and Variegated suppressor 3-9 homolog 1 (SUV39H1) could regulate histone modification of the TWIST1 promoter. We reported that L-NAME increased the expression of TWIST1 in the aortic tissues of ApoE-/- mice fed a high-fat diet (HFD) and RAW264.7 cells treated with ox-LDL. TWIST1 accelerated the development of an unstable atherosclerotic phenotype by promoting macrophage activation, inflammatory factor secretion, macrophage polarization, and lipid phagocytosis. Moreover, we found that H3K9me2 and H3K9me3 in the TWIST1 promoter could be coregulated by LSD1 and SUV39H1, and this process was modulated by CK2α. Taken together, these results revealed that TWIST1 in macrophages is a critical factor that mediates foam cell formation and enhances atherosclerotic plaque vulnerability during hypertension, and targeting TWIST1 may be a promising new therapeutic approach for delaying the progression of AS in hypertension.

Catalpol ameliorates dexamethasone-induced osteoporosis by promoting osteogenic differentiation of bone marrow mesenchymal stem cells via the activation of PKD1 promoter.

OBJECTIVE: To investigate the effects of CA on glucocorticoid-induced osteoporosis (GIOP) and lucubrate the underlying mechanism of CA via the activation of polycystic kidney disease-1(PKD1) in bone marrow mesenchymal stem cells (BMSCs). METHODS: In vivo, a GIOP model in mice treated with dexamethasone (Dex) was established. Biomechanical, micro-CT, immunofluorescence staining of OCN, ALP and PKD1 and others were severally determined. qRT-PCR and Western blot methods were adopted to elucidate the particular mechanisms of CA on GIOP. In addition, BMSCs cultured in vitro were also induced by Dex to verify the effects of CA. Finally, siRNA and luciferase activity assays were performed to confirm the mechanisms. RESULTS: We found that CA could restore the destroyed bone microarchitecture and increase the bone mass in GIOP mice. CA could also upregulate PKD1 protein expression, reduce oxidative stress, and promote mRNA expression of bone formation-associated markers in GIOP mice. Furthermore, it was also observed that CA reduced oxidative stress and promoted osteogenic differentiation in Dex-induced BMSCs. Mechanically, CA could promote protein expression via increasing the activity of PKD1 promoter. CONCLUSION: This study provides important evidences for CA in the further clinical treatment of GIOP, reveals the activation of PKD1 promoter as the underlying mechanism.

The Improvement in Function of Poststroke Spasticity by Vibrational and Heated Stone-Needle Therapy and Meridian Dredging Exercise: A Randomized, Controlled, Preliminary Trial.

BACKGROUND: Poststroke spasticity (PSS) is a common complication of stroke. Current PSS treatments have been linked to high costs, lack of long-term effectiveness, and undesirable side effects. Vibrational and heated stone-needle therapy (VHS) has not been utilized to treat PSS, and its safety and effectiveness have yet to be proven by high-quality clinical research. OBJECTIVE: The aim of this study was to determine the effectiveness of VHS combined with meridian dredging exercise (MDE) in patients with PSS. METHODS: One hundred participants with stroke were included and randomly assigned to a treatment group (VHS plus MDEs) and a control group (MDEs alone). Patients in both groups were treated for 4 weeks. The primary outcome measures were the Modified Ashworth Scale (MAS) and Fugl-Meyer Assessment (FMA), while the secondary outcome measures were the Activity of Daily Living (ADL) Scale and Stroke-Specific Quality of Life Scale (SS-QOL). The evaluations were at baseline (T0) at 4 weeks of treatment (T1) and at 12 weeks of follow-up without treatment (T2). RESULTS: At T1 and T2, there were significant differences in MAS between the two groups (p = 0.001). From the perspective of distribution, the VHS plus MDE group had significant changes, and the group-time interactions of upper and lower extremities in FMA, ADL, and SS-QOL were statistically significant (p < 0.001), indicating that patients' symptoms improved after treatment. But the overall effect size is small, especially the effect size of improvement in SS-QOL at T1. CONCLUSION: VHS in combination with MDE can consistently alleviate PSS, enhance limb function, and improve the quality of life of patients with PSS. But we need to optimize the device further and observe the improvement of patients for a more extended period.Spastik nach Schlaganfall (PSS; post-stroke spasticity) ist eine häufige Komplikation des Schlaganfalls. Gegenwärtige PSS-Behandlungen sind mit hohen Kosten, mangelnder langfristiger Wirksamkeit und unerwünschten Nebenwirkungen in Verbindung gebracht worden. Vibrierende und erhitzte Steinnadeln (VHS) sind bisher nicht zur Behandlung des PSS eingesetzt worden, und der Nachweis ihrer Sicherheit und Wirksamkeit durch hochwertige klinische Forschung steht noch aus.Beurteilung der Wirksamkeit von vibrierenden und erhitzten Steinnadeln (VHS) in Kombination mit Meridian-Ausbagger-Übungen (MDE) bei Patienten mit PSS.100 Patienten mit Schlaganfall wurden eingeschlossen und per Randomisierung auf eine Behandlungsgruppe (VHS plus MDEs) und eine Kontrollgruppe (nur MDE) aufgeteilt. In beiden Gruppen wurden die Patienten 4 Wochen lang behandelt. Die primären Messinstrumente waren die Modified Ashworth Scale (MAS) und das Fugl-Meyer Assessment (FMA), als sekundäre Messinstrumente wurden die Activity of Daily Living Scale (ADL) und die Stroke-Specific Quality of Life Scale (SS-QOL) erhoben. Die Beurteilungszeitpunkte waren bei Baseline (T0) nach 4 Wochen Behandlung (T1) und nach 12 Wochen Nachbeobachtung ohne Behandlung (T2).Bei T1 und T2 bestanden signifikante Unterschiede bei der MAS zwischen den Gruppen (p = 0.001). Aus der Perspektive der Distribution zeigte die "VHS plus MDE"-Gruppe signifikante Veränderungen, und die Gruppe*Zeit-Interaktionen der oberen and unteren Extremitäten bei FMA, ADL und SS-QOL waren statistisch signifikant (p < 0.001), was darauf hindeutet, dass die Beschwerden der Patienten sich nach der Behandlung besserten. Die Effektstärke ist allerdings gering, insbesondere die der SS-QOL-Verbesserung bei T1.Die Anwendung von vibrierenden und erhitzten Steinnadeln in Kombination mit Meridian-Ausbagger-Übungen kann PSS durchgängig lindern, die Funktion der Extremitäten verbessern und die Lebensqualität der Patienten mit PSS erhöhen. Jedoch muss das Produkt weiter optimiert werden, und die Verbesserungen bei den Patienten müssen über einen längeren Zeitraum beobachtet werden.

The experimental approach for the interleaved joint modulation of PHIP and NMR.

Nuclear spin hyperpolarization derived from parahydrogen is a technique for enhancing nuclear magnetic resonance (NMR) sensitivity. The key to hyperpolarization experiments is to achieve rapid transfer and detection to minimize relaxation losses, while also avoiding bubbles or turbulence to guarantee high spectral resolution. In this article, we describe an experimental approach for the interleaved joint modulation of parahydrogen-induced polarization and NMR. We provide schematic diagrams of parahydrogen-based polarizer with in situ high-pressure detection capability and low-field polarization transfer. This approach can help to control the experimental process and acquire experimental information, one example of which is the attainment of the highest hyperpolarization signal intensity at 3.6 s after closing the valve. The polarizer demonstrates in situ detection capability, allowing sample to be restabilized within 0.3 ± 0.1 s and high-resolution NMR sampling under a pressure of 3 bars. Moreover, it can transfer polarized samples from the polarization transfer field to the detection region of NMR within 1 ± 0.3 s for completing signal amplification by reversible exchange experiments.

The Wnt/ß-catenin signaling pathway inhibits osteoporosis by regulating the expression of TERT: an in vivo and in vitro study.

Our study was performed to investigate whether the Wingless and int-1 (Wnt) signaling pathway promotes osteogenic differentiation and inhibits apoptosis in bone marrow mesenchymal stem cells (BMSCs) by regulating telomerase reverse transcriptase (TERT) expression. An in vivo model of osteoporosis (OP) in C57BL/6J mice by bilateral ovariectomy (OVX) and an in vitro model of H2O2-induced BMSCs were established separately. Western blotting was used to detect the expression of the pathway-related proteins TERT, ß-catenin, and phosphorylated-glycogen synthase kinase-3beta (p-GSK3ß)/GSK3ß, the osteogenic-related markers osteopontin (OPN), bone morphogenetic protein 2 (BMP2), and runt-related transcription factor 2 (Runx2), and the apoptosis-related indicators B-cell lymphoma-2 (Bcl-2) and BAX. Osteoblastic phenotypes were also evaluated by alkaline phosphatase (ALP) staining and serum ALP activity assays. Osteogenic differentiation phenotypes in mice were verified by H&E staining, micro-CT, and parameter analysis of the femur. Western blotting results showed that the expression of the pathway-related proteins TERT, ß-catenin, p-GSK3ß/GSK3ß was reduced in OVX mice and H2O2-induced BMSCs, accompanied by downregulated protein expression of osteogenic-related markers and antiapoptotic indicators and upregulated protein expression of apoptotic proteins compared to those in the control group. Mechanistic studies showed that the activation of Wnt signaling pathway in BMSCs promoted ß-catenin translocation to the nucleus, as verified by immunofluorescence and facilitated colocalization between ß-catenin and TERT, as verified by double-labeling immunofluorescence, thereby promoting osteogenic differentiation and reducing apoptosis. In summary, our experiments confirmed that the GSK3ß/ß-catenin/TERT pathway could regulate the osteogenic differentiation and apoptosis of BMSCs and that TERT might be a promising target for the future treatment of osteoporosis.

Circ_0114581 promotes osteogenic differentiation of BMSCs via the MiR-155-5p/HNRNPA3 axis.

Osteoporosis (OP) is a common metabolic bone disease characterized by deterioration of bone tissue structure, reduction of bone mass, and susceptibility to fracture. More and new suitable therapeutic targets need to be discovered. The purpose of this study was to explore the ceRNA mechanisms of circRNAs involved in osteoporosis. In this study, a competing endogenous RNA (ceRNA) regulatory network was obtained through the application of OP-related high throughput data sets. Our results provided evidence that HNRNPA3 was involved in the regulation of osteogenic differentiation in BMSCs. Testing of human bone tissues and ovariectomized mice bones proved that its expression level was negatively correlated with OP. The utilization of miRNA mimic or inhibitor proved that miR-155-5p could negatively regulate the expression of HNRNPA3, while overexpression of hsa_circ_0114581 with a circRNA overexpression vector proved that hsa_circ_0114581 could indirectly promoted HNRNPA3 expression and osteogenic differentiation by sponging hsa-miR-155-5p. A serious of luciferase reporter assay experiments further verified the binding site between miR-155-5p and HNRNPA3 and the binding site between miR-155-5p and hsa_circ_0114581. This study proved that the hsa_circ_0114581/hsa-miR-155-5p/HNRNPA3 axis was related with OP. The results reveal valuable insights into the pathogenesis of OP and noncoding RNA markers that may have a treatment role and will help to provide hypotheses for future studies.

Biomimetic Nacre-like Hydroxyapatite/Polymer Composites for Bone Implants.

One of the most ambitious goals for bone implants is to improve bioactivity, incapability, and mechanical properties; to reduce the need for further surgery; and increase efficiency. Hydroxyapatite (HA), the main inorganic component of bones and teeth, has high biocompatibility but is weak and brittle material. Cortical bone is composed of 70% calcium phosphate (CaP) and 30% collagen and forms a complex hierarchical structure with anisotropic and lamellar microstructure (osteons) which makes bone a light, strong, tough, and durable material that can support large loads. However, imitation of concentric lamellar structure of osteons is difficult to achieve in fabrication. Nacre from mollusk shells with layered structures has now become the archetype of the natural "model" for bio-inspired materials. Incorporating a nacre-like layered structure into bone implants can enhance their mechanical strength, toughness, and durability, reducing the risk of implant catastrophic failure or fracture. The layered structure of nacre-like HA/polymer composites possess high strength, toughness, and tunable stiffness which matches that of bone. The nacre-like HA/polymer composites should also possess excellent biocompatibility and bioactivity which facilitate the bonding of the implant with the surrounding bone, leading to improved implant stability and long-term success. To achieve this, a bi-directional freeze-casting technique was used to produce elongated lamellar HA were further densified and infiltrated with polymer to produce nacre-like HA/polymer composites with high strength and fracture toughness. Mechanical characterization shows that increasing the ceramic fractions in the composite increases the density of the mineral bridges, resulting in higher flexural and compressive strength. The nacre-like HA/(methyl methacrylate (MMA) + 5 wt.% acrylic acid (AA)) composites with a ceramic fraction of 80 vol.% showed a flexural strength of 158 ± 7.02 MPa and a Young's modulus of 24 ± 4.34 GPa, compared with 130 ± 5.82 MPa and 19.75 ± 2.38 GPa, in the composite of HA/PMMA, due to the higher strength of the polymer and the interface of the composite. The fracture toughness in the composition of 5 wt.% PAA to PMMA improves from 3.023 ± 0.98 MPa·m1/2 to 5.27 ± 1.033 MPa·m1/2 by increasing the ceramic fraction from 70 vol.% to 80 vol.%, respectively.

Ganoderma lucidum polysaccharide peptide (GLPP) attenuates rheumatic arthritis in rats through inactivating NF-κB and MAPK signaling pathways.

BACKGROUND: Not many drugs with fewer side effects are available for the treatment of rheumatoid arthritis (RA). Ganoderma lucidum polysaccharide peptide (GLPP) has good immunomodulatory effects, but whether it is effective in managing RA is not clear. PURPOSE: This study was conducted to examine the anti-RA activity and possible mechanisms of GLPP in collagen-induced arthritis (CIA) rats. METHODS: Male Wistar rats were intradermally injected with bovine type II collagen in the tail base to establish the CIA model and were orally administered 100 or 200 mg/kg GLPP for 35 days. Paw thickness, clinical arthritis scores, gait analysis, organ index determination, blood cell counts, micro-CT imaging and pathological staining were performed on the rats. Liver and kidney function were measured by commercial kits, and antibody levels were measured by ELISA kits. RA-related protein levels were detected by Western blotting. RESULTS: GLPP effectively alleviated CIA symptoms and reduced immune organ indexes, antibody levels and systemic organ injury. GLPP decreased the protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, matrix metalloproteinase (MMP)2, MMP9, MMP13, BCL-2, OPN, ß-Catenin, and hypoxia inducible factor (HIF)-1α and increased the protein expression of BAX in the joint tissues of CIA rats. Moreover, GLPP decreased the phosphorylation levels of p65, IκB-α and ERK1/2. CONCLUSION: GLPP effectively alleviated RA symptoms in CIA rats by inhibiting the NF-κB and MAPK pathways. This study suggests a promising therapeutic effect of mushroom-derived polysaccharide peptides on RA.

SABRE Hyperpolarization of Exchangeable Protons in Methanol-d4 through Dynamic Covalent Bonds.

Utilizing para-hydrogen (p-H2)-induced hyperpolarization to increase the sensitivity of nuclear magnetic resonance, especially signal amplification by reversible exchange (SABRE), has been widely studied. Here, we achieved hyperpolarization of exchangeable protons in methanol-d4 by introducing dynamic covalent bonds as reversible exchange following the SABRE process. To release the hyperpolarized CD3OH, the pyridine-based ligands with aldehyde groups underwent acetal exchange between the aldehyde and hydroxyl groups of CD3OH after being first hyperpolarized by SABRE. Our mechanistic study highlights the importance of the reversible exchange of functional groups and chemical kinetics in realizing hyperpolarization of exchangeable protons in methanol-d4. Our work broadens SABRE's chemical system compatibility and possible applications.

BMSC-derived extracellular vesicles promoted osteogenesis via Axin2 inhibition by delivering MiR-16-5p.

Osteoporosis (OP) is a systemic bone disease caused by an imbalance in osteogenesis and osteoclastic resorption. Extracellular vesicles (EVs)-encapsulated miRNAs from bone mesenchymal stem cells (BMSCs) have been reported to participate in osteogenesis. MiR-16-5p is one of the miRNAs that regulates osteogenic differentiation; however, studies have shown that its role in osteogenesis is controversial. Thus, this study aims to investigate the role of miR-16-5p from BMSC-derived extracellular vesicles (EVs) in osteogenic differentiation and uncover the underlying mechanisms. In this study, we used an ovariectomized (OVX) mouse model and an H2O2-treated BMSCs model to investigate the effects of BMSC-derived EVs and EV-encapsulated miR-16-5p on OP and the underlying mechanisms. Our results proved that the miR-16-5p level was significantly decreased in H2O2-treated BMSCs, bone tissues of OVX mice, and lumbar lamina tissues from osteoporotic women. EVs-encapsulated miR-16-5p from BMSCs could promote osteogenic differentiation. Moreover, the miR-16-5p mimics promoted osteogenic differentiation of H2O2-treated BMSCs, and the effects exerted by miR-16-5p were mediated by targeting Axin2, a scaffolding protein of GSK3ß that negatively regulates the Wnt/ß-catenin signaling pathway. This study provides evidence that EVs-encapsulated miR-16-5p from BMSCs could promote osteogenic differentiation by repressing Axin2.