AtomNet-Aided OTUD7B Inhibitor Discovery and Validation

Protein deubiquitinases play critical pathophysiological roles in cancer. Among all deubiquitinases, an oncogenic function for OTUD7B has been established in genetic NSCLC murine models. However, few deubiquitinase inhibitors have been developed due to technical challenges. Here, we report a putative small molecule OTUD7B inhibitor obtained from an AI-aided screen of a 4 million compound library. We validated the effects of the OTUD7B inhibitor (7Bi) in reducing Akt-pS473 signals in multiple NSCLC and HEK293 cells by blocking OTUD7B-governed GβL deubiquitination in cells, as well as inhibiting OTUD7B-mediated cleavage of K11-linked di-ub in an in vitro enzyme assay. Furthermore, we report in leukemia cells, either genetic depletion or 7Bi-mediated pharmacological inhibition of OTUD7B reduces Akt-pS473 via inhibiting the OTUD7B/GβL signaling axis. Together, our study identifies the first putative OTUD7B inhibitor showing activities both in cells and in vitro, with promising applications as a therapeutic agent in treating cancer with OTUD7B overexpression.

Recent Progress in Nanomaterial-Based Biosensors and Theranostic Nanomedicine for Bladder Cancer

Bladder cancer (BCa) is one of the most expensive and common malignancies in the urinary system due to its high progression and recurrence rate. Although there are various methods, including cystoscopy, biopsy, and cytology, that have become the standard diagnosis methods for BCa, their intrinsic invasive and inaccurate properties need to be overcome. The novel urine cancer biomarkers are assisted by nanomaterials-based biosensors, such as field-effect transistors (FETs) with high sensitivity and specificity, which may provide solutions to these problems. In addition, nanomaterials can be applied for the advancement of next-generation optical imaging techniques and the contrast agents of conventional techniques; for example, magnetic resonance imaging (MRI) for the diagnosis of BCa. Regarding BCa therapy, nanocarriers, including mucoadhesive nanoparticles and other polymeric nanoparticles, successfully overcome the disadvantages of conventional intravesical instillation and improve the efficacy and safety of intravesical chemotherapy for BCa. Aside from chemotherapy, nanomedicine-based novel therapies, including photodynamic therapy (PDT), photothermal therapy (PTT), chemodynamic therapy (CDT), sonodynamic therapy (SDT), and combination therapy, have afforded us new ways to provide BC therapy and hope, which can be translated into the clinic. In addition, nanomotors and the nanomaterials-based solid tumor disassociation strategy provide new ideas for future research. Here, the advances in BCa diagnosis and therapy mentioned above are reviewed in this paper.

Anesthesia with ciprofol in cardiac surgery with cardiopulmonary bypass: A case report

BACKGROUND

Ciprofol is a novel agent for intravenous general anesthesia. In February 2022, it was approved by the National Medical Products Administration for general anesthesia induction and maintenance. It has the advantages of fast onset, fast elimination, stable circulation, and few adverse reactions. However, the efficacy and safety of ciprofol in cardiac surgery with cardiopulmonary bypass have not been reported. Here we describe a case where ciprofol was successfully used for anesthesia in cardiac surgery with cardiopulmonary bypass.

CASE SUMMARY

A 72-year-old man (height 176 cm; weight 70 kg) was diagnosed with coronary atherosclerotic cardiomyopathy requiring coronary artery bypass grafting and left ventricular aneurysmectomy. Ciprofol was administered for induction (0.4 mg/kg) and maintenance (0.6-1.0 mg/kg/h) of general anesthesia. During the entire operation, the bispectral index, hemodynamics, and blood oxygen saturation were maintained at normal levels. The patient recovered well after surgery, with no serious adverse events related to ciprofol.

CONCLUSION

Ciprofol is safe and effective for anesthesia in cardiac surgery with cardiopulmonary bypass.

Habitat quality dynamics in China's first group of national parks in recent four decades: Evidence from land use and land cover changes

As the most biodiversity-rich part of the protected areas system, habitats within the pilot national parks have long been threatened by drastic human-induced land use and land cover changes. The growing concern about habitat loss has spurred China's national park project to shift from pilot to construction phase with the official establishment of China's first group of national parks (CFGNPs) in October 2021. But far too little attention has been paid to the synergistic work concerning the habitat quality (HQ) dynamics of all five national parks. Here, the InVEST model, combined with a satellite-derived land use and land cover product and a hot spot analysis (HSA) method, was used to investigate the HQ dynamics at the park- and pixel-scale within the CFGNPs. Our results demonstrate that the past ecological conservation practices within national parks have been unpromising, especially in Giant Panda National Park, Northeast China Tiger and Leopard National Park (NCTL), and Wuyi Mountain National Park (WYM), where HQ as a whole showed a significant decline. Furthermore, more than half of Hainan Tropical Rainforest National Park (87.2%), WYM (77.4%), and NCTL (52.9%) showed significant HQ degradation from 1980 to 2019. Besides, increasing trends in the area shares of HQ degraded pixels were observed in all five national parks from 1980-1999 to 2000-2019. The HSA implied that the hot spots of high HQ degradation rates tend to occur in areas closer to urban settlements or on the edge of national parks, where human activities are intensive. Despite these disappointing findings, we highlighted from the observed local successes and the HQ plateau that the construction of CFGNPs is expected to reverse the deteriorating HQ trends. Thus, we concluded our paper by proposing an HSA-based regulatory zoning scheme that includes five subzones to guide the future construction of China's national park system.

Identification of NETs-related biomarkers and molecular clusters in systemic lupus erythematosus

Neutrophil extracellular traps (NETs) is an important process involved in the pathogenesis of systemic lupus erythematosus (SLE), but the potential mechanisms of NETs contributing to SLE at the genetic level have not been clearly investigated. This investigation aimed to explore the molecular characteristics of NETs-related genes (NRGs) in SLE based on bioinformatics analysis, and identify associated reliable biomarkers and molecular clusters. Dataset GSE45291 was acquired from the Gene Expression Omnibus repository and used as a training set for subsequent analysis. A total of 1006 differentially expressed genes (DEGs) were obtained, most of which were associated with multiple viral infections. The interaction of DEGs with NRGs revealed 8 differentially expressed NRGs (DE-NRGs). The correlation and protein-protein interaction analyses of these DE-NRGs were performed. Among them, HMGB1, ITGB2, and CREB5 were selected as hub genes by random forest, support vector machine, and least absolute shrinkage and selection operator algorithms. The significant diagnostic value for SLE was confirmed in the training set and three validation sets (GSE81622, GSE61635, and GSE122459). Additionally, three NETs-related sub-clusters were identified based on the hub genes' expression profiles analyzed by unsupervised consensus cluster assessment. Functional enrichment was performed among the three NETs subgroups, and the data revealed that cluster 1 highly expressed DEGs were prevalent in innate immune response pathways while that of cluster 3 were enriched in adaptive immune response pathways. Moreover, immune infiltration analysis also revealed that innate immune cells were markedly infiltrated in cluster 1 while the adaptive immune cells were upregulated in cluster 3. As per our knowledge, this investigation is the first to explore the molecular characteristics of NRGs in SLE, identify three potential biomarkers (HMGB1, ITGB2, and CREB5), and three distinct clusters based on these hub biomarkers.

3D-US and CBCT Dual-guided Radiotherapy for Postoperative Uterine Malignancy: A Primary Workflow Set-up

Introduction: The consistency of clinical target volume is essential to guiding radiotherapy with precision for postoperative uterine malignancy patients. By introducing a three-dimensional ultrasound system (3D-US) into image-guided radiation therapy (IGRT), this study was designed to investigate the initial workflow set-up, the therapeutic potential, and the adverse events of 3D-US and cone-beam computed tomography (CBCT) dual-guided radiotherapy in postoperative uterine malignancy treatment. Methods: From April 2021 to December 2021, postoperative uterine malignancy patients were instructed to follow the previously standard protocol of daily radiation treatment, particularly a 3D-US (Clarity system) guiding was involved before CBCT. Soft-tissue-based displacements resulting from the additional US-IGRT were acquired in the LT (left)/RT (right), ANT (anterior)/POST (posterior), and SUP (superior)/INF(inferior) directions of the patient before fractional treatment. Displacement distributions before and after treatment either from 3D-US or from CBCT were also estimated and compared subsequently, and the urinary and rectal toxicity was further evaluated. Results: All the patients completed radiation treatment as planned. The assessment of 170 scans resulted in a mean displacement of (0.17 ± 0.24) cm, (0.19 ± 0.23) cm, (0.22 ± 0.26) cm for bladder in LT/RT, ANT/POST, and SUP/INF directions. A mean deviation of (0.26 ± 0.22) cm, (0.58 ± 0.5) cm, and (0.3 ± 0.23) cm was also observed for the bladder centroid between the CBCT and computed tomography -simulation images in three directions. Paired comparison between these two guidance shows that the variations from 3D-US are much smaller than those from CBCT in three directions, especially in ANT/POST and SUP/INF directions with significance (P = 0.000, 0.001, respectively). During treatment, and 0, 3, 6, 9, and 12 months after treatment, there was no severe urinary and rectal toxicity happened. Conclusion: A primary workflow of 3D-US and CBCT dual-guided radiotherapy has been established, which showed great therapeutic potential with mild to moderate urinary and rectal toxicity for postoperative uterine malignancy patients. But the clinical outcomes of this non-invasive technique need to be investigated further.

Polyaniline coated Pt/CNT as highly stable and active catalyst for catalytic hydrogenation reduction of Cr(VI)

Liquid phase catalytic hydrogenation reduction is a feasible method to eliminate Cr(VI) in water, while supported noble metal catalysts are liable to deactivation. In this study, carbon nanotube supported Pt catalyst (Pt/CNT) coated by polyaniline (Pt/CNT@PANI) was prepared and applied in the liquid phase catalytic hydrogenation of Cr(VI). Characterization results disclose that after coating Pt/CNT is completely wrapped by PANI layers and active Pt particles are no longer accessible. Despite complete embedment of Pt particles by PANI layers, Pt/CNT@PANI remains highly active for Cr(VI) reduction in liquid phase catalytic hydrogenation. The catalytic Cr(VI) reduction on Pt/CNT@PANI can be described by a PANI oxidation-reduction mechanism, by which PANI is first oxidized by Cr(VI) to form Cr(III), and oxidized PANI is reduced by catalytic hydrogenation. The Cr(VI) reduction on Pt/CNT@PANI complies with the Langmuir-Hinshelwood model, reflecting the pivotal role of Cr(VI) adsorption. Furthermore, the catalytic activity of Pt/CNT@PANI differs with PANI layer thickness and Cr(VI) reduction is positively correlated with reaction temperature. Catalyst recycling results show that after 4 cycles Pt/CNT loses 92.4% of catalytic activity, while the initial activity of Pt/CNT@PANI slightly decreases by 11.6%, demonstrating its high catalyst stability.

Spatiotemporal differences in riverine nitrogen and phosphorus fluxes and associated drivers across China from 1980 to 2018

Increases in nutrient loadings to waterways over the past four decades have led to widespread eutrophication and water quality impairments across China. Understanding the spatial, interannual and long-term variations in nutrient loadings and associated drivers at the national scale is crucial for developing effective nutrient reduction strategies. However, the controls on, and spatiotemporal variations in, nutrient fluxes remain a problem from both an academic and management perspective. This study provides spatially extensive and temporally contiguous estimates of changes in riverine total nitrogen (TN), ammonia nitrogen (NH₃-N) and total phosphorus (TP) fluxes for continental area of China based on machine learning stack models and empirical modeling over the period from 1980 to 2018. Results reveal considerable spatial, interannual and long-term variability in annual TN, NH₃-N and TP fluxes, with spatial variations in average TN and NH₃-N fluxes primarily driven by net anthropogenic nitrogen inputs. Interannual variability is dominated by precipitation across continental areas of China. Spatial variability in the estimated average annual TP flux in the undeveloped western and the developed middle east regions of China are primarily controlled by net anthropogenic phosphorus inputs and precipitation, respectively. We found that TN, NH₃-N and TP fluxes increased from 1980 to 2018 in watersheds in East China; the national mean annual TN, NH₃-N and TP fluxes increased before 2015 and decreased after 2015. This study illustrates the important role of precipitation and temperature variability in controlling the spatial, interannual and long-term variability of nutrient fluxes, and indicates that the influence of the meteorological conditions on annual loadings is needed when designing watershed nutrient reduction or management strategies.

The occupational anxiety of teachers caused by China's 'double reduction' policy-a study based on the grounded theory

Teachers' occupational anxiety is a kind of negative emotional state of teachers, which is prevalent in Chinese teachers. Unfortunately, in the existing research, teachers' occupational anxiety caused by China's 'double reduction' policy has not been paid attention to. Based on the grounded theory, this study conducted in-depth interviews with 45 in-service primary and junior high school teachers, and used NVivo 12 to process recording materials. Through a series of steps such as open coding, axial coding and selective coding, we found that the core feature of teachers' occupational anxiety caused by the 'double reduction' policy was that the implementation of the 'double reduction' policy was incomplete matching the actual educational ecology. Then we constructed a theoretical model of the formation mechanism of teachers' occupational anxiety caused by the 'double reduction' policy. The study showed that due to the influence of teachers' own personality characteristics and incomplete match between external factors, although teachers insisted on self-adjustment, it was difficult to fundamentally solve the teachers' occupational anxiety caused by the 'double reduction' policy.

Wheat yield estimation using remote sensing data based on machine learning approaches

Accurate predictions of wheat yields are essential to farmers'production plans and to the international trade in wheat. However, only poor approximations of the productivity of wheat crops in China can be obtained using traditional linear regression models based on vegetation indices and observations of the yield. In this study, Sentinel-2 (multispectral data) and ZY-1 02D (hyperspectral data) were used together with 15709 gridded yield data (with a resolution of 5 m × 5 m) to predict the winter wheat yield. These estimates were based on four mainstream data-driven approaches: Long Short-Term Memory (LSTM), Random Forest (RF), Gradient Boosting Decision Tree (GBDT), and Support Vector Regression (SVR). The method that gave the best estimate of the winter wheat yield was determined, and the accuracy of the estimates based on multispectral and hyperspectral data were compared. The results showed that the LSTM model, for which the RMSE of the estimates was 0.201 t/ha, performed better than the RF (RMSE = 0.260 t/ha), GBDT (RMSE = 0.306 t/ha), and SVR (RMSE = 0.489 t/ha) methods. The estimates based on the ZY-1 02D hyperspectral data were more accurate than those based on the 30-m Sentinel-2 data: RMSE = 0.237 t/ha for the ZY-1 02D data, which is about a 5% improvement on the RSME of 0.307 t/ha for the 30-m Sentinel-2 data. However, the 10-m Sentinel-2 data performed even better, giving an RMSE of 0.219 t/ha. In addition, it was found that the greenness vegetation index SR (simple ratio index) outperformed the traditional vegetation indices. The results highlight the potential of the shortwave infrared bands to replace the visible and near-infrared bands for predicting crop yields Our study demonstrates the advantages of the deep learning method LSTM over machine learning methods in terms of its ability to make accurate estimates of the winter wheat yield.

Comparing clinical characteristics of systemic sclerosis with or without interstitial lung disease: A cross-sectional study from a single center of the Chinese Rheumatism Data Center

Background

We aimed to compare the clinical characteristics of patients with systemic sclerosis (SSc) with or without interstitial lung disease (ILD) to identify relationships with the presence of ILD in SSc at a single center in China.

Methods

A cross-sectional study was conducted using retrospective data from the Chinese Rheumatology Data Center. Patients diagnosed with SSc at the Second Affiliated Hospital of Nanchang University between 2013 and 2022 were included. Demographic and clinical characteristics were compared between patients with SSc with and without ILD. Logistic regression analyses were performed to explore these associations.

Results

A total of 227 patients with SSc were included (male:female ratio = 1:4.82), of which 121 (53.3%) were accompanied with ILD. SSc patients with ILD had a higher percentage of diffuse cutaneous systemic sclerosis (dcSSc), sclerodactyly, loss of finger pad, muscle involvement, left ventricular diastolic dysfunction (LVDD), and pulmonary hypertension (PAH), elevated Krebs von den Lungen-6 (KL-6), and elevated ferritin than those without ILD, and a higher modified Rodnan skin score (mRSS), neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) (all P < 0.05). Antinuclear antibody (ANA) and anti-scleroderma-70 (anti-Scl-70) positivity was presented frequently in SSc patients with ILD, while SSc patients without ILD were more often anti-centromere antibody (ACA) positive (all P < 0.05). On the multivariable analysis, muscle involvement [OR 2.551 (95% CI 1.054-6.175), P = 0.038], LVDD [OR 2.360 (95% CI 1.277-4.361), P = 0.006], PAH [OR 9.134 (95% CI 2.335-35.730), P = 0.001], dcSSc [OR 2.859 (95% CI 1.489-5.487), P = 0.002], PLR [OR 1.005 (95% CI 1.001-1.008), P = 0.020], elevated KL-6 [OR 2.033 (95% CI 1.099-3.763), P = 0.024], and anti-Scl-70 [OR 3.101 (95% CI 1.647-5.840), P < 0.001] were statistically significant associations with SSc patients with ILD.

Conclusion

Systemic sclerosis was found mainly in females. Several important differences in clinical and laboratory characteristics have been demonstrated between SSc patients with or without ILD. Muscle involvement, LVDD, PAH, dcSSc, PLR, elevated KL-6, and Anti-Scl-70 antibody may be associated with SSc in patients with ILD.

Effects of airflow rate and plant species on formaldehyde removal by active green walls

Formaldehyde is a hazardous volatile organic compound (VOC) listed as a Group 1 carcinogen by the International Agency for Research on Cancer. The active green wall system is a promising technology that utilizes active airflow passing through plants grown along a vertical alignment to increase their mass exposure to pollutants. However, few studies have investigated the effect of airflow rate on their efficacy for formaldehyde removal, and plant-mediated effects are unknown. This study assessed the formaldehyde removal ability of the active green wall using dynamic experiments. Three levels of airflow rate (30, 50, and 65 m³·h^-1) and inlet formaldehyde concentration (1.0, 2.0, and 3.5 mg·m^-3) were used and three plant species were investigated. The removal of formaldehyde by active green walls was significantly (P < 0.01) affected by the airflow rate, formaldehyde concentration, and plant species. The single pass removal efficiency varying from 38.18 to 94.42% decreased as the airflow rate and formaldehyde concentration increased. The elimination capacity varied from 189 to 1154 mg·m^-2·h^-1 and increased with the inlet formaldehyde loading rate. Significant differences in formaldehyde removal effectiveness among the plant species were observed with Chlorophytum comosum performing the best, followed by Schefflera octophylla, with Chamaedorea elegans being the worst.

High-Rate Organic Cathode Constructed by Iron-Hexaazatrinaphthalene Tricarboxylic Acid Coordination Polymer for Li-Ion Batteries

The sluggish ion-transport in electrodes and low utilization of active materials are critical limitations of organic cathodes, which lead to the slow reaction dynamics and low specific capacity. In this study, the hierarchical tube is constructed by iron-hexaazatrinaphthalene tricarboxylic acid coordination polymer (Fe-HATNTA), using HATNTA as the self-engaged template to coordinate with Fe²⁺ ions. This Fe-HATNTA tube with hierarchical porous structure ensures the sufficient contact between electrolyte and active materials, shortens the diffusion distance, and provides more favorable transport pathways for ions. When employed as the cathode for rechargeable Li-ion batteries, Fe-HATNTA delivers a high specific capacity (244 mAh g^-1 at 50 mA g^-1 , 91% of theoretical capacity), excellent rate capability (128 mAh g^-1 at 9 A g^-1 ), and a long-term cycle life (73.9% retention over 3000 cycles at 5 A g^-1 ). Moreover, the Li⁺ ions storage and conduction mechanisms are further disclosed by the ex situ and in situ characterizations, kinetic analyses, and theoretical calculations. This work is expected to boost further enthusiasm for developing the hierarchical structured metal-organic coordination polymers with superb ionic storage and transport as high-performance organic cathodes.

CDH17 nanobodies facilitate rapid imaging of gastric cancer and efficient delivery of immunotoxin

BACKGROUND

It is highly desirable to develop new therapeutic strategies for gastric cancer given the low survival rate despite improvement in the past decades. Cadherin 17 (CDH17) is a membrane protein highly expressed in cancers of digestive system. Nanobody represents a novel antibody format for cancer targeted imaging and drug delivery. Nanobody targeting CHD17 as an imaging probe and a delivery vehicle of toxin remains to be explored for its theragnostic potential in gastric cancer.

METHODS

Naïve nanobody phage library was screened against CDH17 Domain 1-3 and identified nanobodies were extensively characterized with various assays. Nanobodies labeled with imaging probe were tested in vitro and in vivo for gastric cancer detection. A CDH17 Nanobody fused with toxin PE38 was evaluated for gastric cancer inhibition in vitro and in vivo.

RESULTS

Two nanobodies (A1 and E8) against human CDH17 with high affinity and high specificity were successfully obtained. These nanobodies could specifically bind to CDH17 protein and CDH17-positive gastric cancer cells. E8 nanobody as a lead was extensively determined for tumor imaging and drug delivery. It could efficiently co-localize with CDH17-positive gastric cancer cells in zebrafish embryos and rapidly visualize the tumor mass in mice within 3 h when conjugated with imaging dyes. E8 nanobody fused with toxin PE38 showed excellent anti-tumor effect and remarkably improved the mice survival in cell-derived (CDX) and patient-derived xenograft (PDX) models. The immunotoxin also enhanced the anti-tumor effect of clinical drug 5-Fluorouracil.

CONCLUSIONS

The study presents a novel imaging and drug delivery strategy by targeting CDH17. CDH17 nanobody-based immunotoxin is potentially a promising therapeutic modality for clinical translation against gastric cancer.

The role of the immune microenvironment in bone, cartilage, and soft tissue regeneration: from mechanism to therapeutic opportunity

Bone, cartilage, and soft tissue regeneration is a complex spatiotemporal process recruiting a variety of cell types, whose activity and interplay must be precisely mediated for effective healing post-injury. Although extensive strides have been made in the understanding of the immune microenvironment processes governing bone, cartilage, and soft tissue regeneration, effective clinical translation of these mechanisms remains a challenge. Regulation of the immune microenvironment is increasingly becoming a favorable target for bone, cartilage, and soft tissue regeneration; therefore, an in-depth understanding of the communication between immune cells and functional tissue cells would be valuable. Herein, we review the regulatory role of the immune microenvironment in the promotion and maintenance of stem cell states in the context of bone, cartilage, and soft tissue repair and regeneration. We discuss the roles of various immune cell subsets in bone, cartilage, and soft tissue repair and regeneration processes and introduce novel strategies, for example, biomaterial-targeting of immune cell activity, aimed at regulating healing. Understanding the mechanisms of the crosstalk between the immune microenvironment and regeneration pathways may shed light on new therapeutic opportunities for enhancing bone, cartilage, and soft tissue regeneration through regulation of the immune microenvironment.

Alternative Pathway to Phase Down Coal Power and Achieve Negative Emission in China

Although widely recognized as the key to climate goals, coal "phase down" has long been argued for its side effects on energy security and social development. Retrofitting coal power units with biomass and coal co-firing with a carbon capture and storage approach provides an alternative way to avoid these side effects and make deep carbon dioxide emission cuts or even achieve negative emission. However, there is a lack of clear answers to how much the maximum emission reduction potential this approach can unlock, which is the key information to promote this technology on a large scale. Here, we focus on helping China's 4536 coal power units make differentiated retrofit choices based on unit-level heterogeneity information and resource spatial matching results. We found that China's coal power units have the potential to achieve 0.4 Gt of negative CO₂ emission in 2025, and the cumulative negative CO₂ emission would reach 10.32 Gt by 2060. To achieve negative CO₂ emission, the biomass resource amount should be 1.65 times the existing agricultural and forestry residues, and the biomass and coal co-firing ratio should exceed 70%. Coal power units should grasp their time window; otherwise, the maximum negative potential would decrease at a rate of 0.35 Gt per year.

Identifying ecosystem service value and potential loss of wilderness areas in China to support post-2020 global biodiversity conservation

Preserving wilderness areas is one of the key goals in the Post-2020 Global Biodiversity Framework(GBF). However, far too little attention has been paid to identifying wilderness conservation priorities on the national scale. In this study, we developed a methodological framework to evaluate the ecosystem service values, potential loss and conservation priorities of wilderness areas in China, providing guidance for wilderness conservation. First, we assessed the conservation value of wilderness areas and found that wilderness areas provided more ecosystem services than non-wilderness areas per unit area in most ecoregions. Then we identified threatened wilderness areas under multiple scenarios due to land use and land cover change. We found that 5.82 % of the existing wilderness areas were projected to be lost by 2100. Finally, wilderness conservation priorities were identified considering both conservation values and potential loss, and 11.24 % of existing wilderness areas were highlighted as conservation priorities. This methodological framework could be applied to other countries to support post-2020 global biodiversity conservation.

Extracellular vesicles derived from mesenchymal stem cells confer protection against intervertebral disc degeneration through a microRNA-217-dependent mechanism

OBJECTIVE

Extracellular vesicles released by mesenchymal stem cells (MSC-EVs) can be applied to alleviate intervertebral disc degeneration (IVDD) by curbing apoptosis of nucleus pulposus cells (NPCs). The current study aims to evaluate the effect of MSC-EVs on NPC apoptosis and IVDD and the related regulatory mechanisms involving microRNA (miR)-217.

METHOD

Expression of miR-217 was examined in tumor necrosis factor-α (TNF-α)-induced NPCs and MSC-EVs, followed by identification in the relationship between miR-217, enhancer of zeste homolog 2 (EZH2) and forkhead box O-3 (FOXO3). After isolation of EVs from MSCs and subsequent co-culture with NPCs, we assessed effects of miR-217 on NPC viability, autophagy, senescence and apoptosis along with extracellular matrix (ECM) degradation. Further in vivo experiments were conducted in rat models of IVDD to substantiate the effect of miR-217 on IVDD.

RESULTS

Poor miR-217 expression was found in TNF-α-induced NPCs, while high miR-217 expression was identified in MSC-EVs (P < 0.05). MSC-EVs transferred miR-217 to NPCs and increased its expression, thus attenuating NPC apoptosis and ECM degradation (elevated collagen II and aggrecan but reduced MMP13 and ADAMTS5) (P < 0.05). miR-217 targeted EZH2, and EZH2 bound to the FOXO3 promoter and consequently downregulated its expression. FOXO3 restrained NPC apoptosis and ECM degradation by stimulating cell autophagy (P < 0.05). Furthermore, in vivo experimental results confirmed the suppressive role of miR-217 shuttled by MSC-EVs in IVDD.

CONCLUSION

Overall, the delivery of miR-217 may be a novel mechanism underlying the effect of MSC-EVs on NPC apoptosis and ECM degradation following IVDD.