An integrated multi-omics analysis reveals osteokines involved in global regulation

Bone secretory proteins, termed osteokines, regulate bone metabolism and whole-body homeostasis. However, fundamental questions as to what the bona fide osteokines and their cellular sources are and how they are regulated remain unclear. In this study, we analyzed bone and extraskeletal tissues, osteoblast (OB) conditioned media, bone marrow supernatant (BMS), and serum, for basal osteokines and those responsive to aging and mechanical loading/unloading. We identified 375 candidate osteokines and their changes in response to aging and mechanical dynamics by integrating data from RNA-seq, scRNA-seq, and proteomic approaches. Furthermore, we analyzed their cellular sources in the bone and inter-organ communication facilitated by them (bone-brain, liver, and aorta). Notably, we discovered that senescent OBs secrete fatty-acid-binding protein 3 to propagate senescence toward vascular smooth muscle cells (VSMCs). Taken together, we identified previously unknown candidate osteokines and established a dynamic regulatory network among them, thus providing valuable resources to further investigate their systemic roles.

Whitening of brown adipose tissue inhibits osteogenic differentiation via secretion of S100A8/A9

The mechanism by which brown adipose tissue (BAT) regulates bone metabolism is unclear. Here, we reveal that BAT secretes S100A8/A9, a previously unidentified BAT adipokine (batokine), to impair bone formation. Brown adipocytes-specific knockout of Rheb (RhebBAD KO), the upstream activator of mTOR, causes BAT malfunction to inhibit osteogenesis. Rheb depletion induces NF-κB dependent S100A8/A9 secretion from brown adipocytes, but not from macrophages. In wild-type mice, age-related Rheb downregulation in BAT is associated with enhanced S100A8/A9 secretion. Either batokines from RhebBAD KO mice, or recombinant S100A8/A9, inhibits osteoblast differentiation of mesenchymal stem cells in vitro by targeting toll-like receptor 4 on their surfaces. Conversely, S100A8/A9 neutralization not only rescues the osteogenesis repressed in the RhebBAD KO mice, but also alleviates age-related osteoporosis in wild-type mice. Collectively, our data revealed an unexpected BAT-bone crosstalk driven by Rheb-S100A8/A9, uncovering S100A8/A9 as a promising target for the treatment, and potentially, prevention of osteoporosis.

Chickpea-Derived Modified Antimicrobial Peptides KTA and KTR Inactivate Staphylococcus aureus via Disrupting Cell Membrane and Interfering with Peptidoglycan Synthesis

The widespread bacterial contamination caused by foodborne pathogens has continuously driven the development of advanced and potent food antimicrobial agents. In this study, two novel antimicrobial peptides (AMPs) named KTA and KTR were obtained by modifying a natural AMP, Leg2, from chickpea storage protein legumin hydrolysates. They were further predicted to be stable hydrophobic cationic AMPs of α-helical structure with no hemolytic toxicity by several online servers. Moreover, the AMPs exerted superior antibacterial activity against two representative Staphylococcus aureus strains thanks to the increased hydrophobicity and positive charge, with minimum inhibition concentration value (4.74-7.41 μM) significantly lower than that of Leg2 (>1158.70 μM). Further, this study sought to elucidate the specific antimicrobial mechanism against Gram-positive bacteria. It was found that the electrostatic interactions of the AMPs with peptidoglycan were vital for peptide activity in combating Gram-positive bacteria. Subsequently, the cell membrane of S. aureus cells was irreversibly disrupted by increasing permeability and impairing membrane components, which led to the massive release of intracellular substances and eventual cell death. Overall, this work demonstrated that KTA and KTR were active against Gram-positive bacteria via peptidoglycan targeting and membrane-disruptive mechanisms and paved the way for expanding their application potential to alleviate food contamination.

ANGPTL4 binds to the leptin receptor to regulate ectopic bone formation

Leptin protein was thought to be unique to leptin receptor (LepR), but the phenotypes of mice with mutation in LepR [db/db (diabetes)] and leptin [ob/ob (obese)] are not identical, and the cause remains unclear. Here, we show that db/db, but not ob/ob, mice had defect in tenotomy-induced heterotopic ossification (HO), implicating alternative ligand(s) for LepR might be involved. Ligand screening revealed that ANGPTL4 (angiopoietin-like protein 4), a stress and fasting-induced factor, was elicited from brown adipose tissue after tenotomy, bound to LepR on PRRX1+ mesenchymal cells at the HO site, thus promotes chondrogenesis and HO development. Disruption of LepR in PRRX1+ cells, or lineage ablation of LepR+ cells, or deletion of ANGPTL4 impeded chondrogenesis and HO in mice. Together, these findings identify ANGPTL4 as a ligand for LepR to regulate the formation of acquired HO.

Optimizing physico-chemical properties of hierarchical ZnO/TiO2 nano-film by the novel heating method for photocatalytic degradation of antibiotics and dye

The design of semiconductor catalysts with excellent photocatalytic properties, stability, recyclability, and good separation for the treatment of polluted water is still challenging. In this paper, the ZnO/TiO2 nano-thin films were fabricated using the magnetron sputtering technique and then heating the underlying ZnO layer and the upper TiO2 layer for their respective optimal heating time, i. e. heating ZnO for 3 h and heating TiO2 for 2 h. The as-prepared films were characterized. The results show that the preferred growth of TiO2 grains along the [001] axis, relatively large specific surface area, and increased amounts of surface oxygen vacancies (OVs) were induced to the heterojunction catalysts through this optimized heating strategy, which boosts the photocatalytic activity of ZnO/TiO2 nano-film. The degradation experiment inndicates that the ciprofloxacin (CIP) removal efficiency can reach 97.3% in 2 h duration, which was higher than that of the samples annealed for the same periods. Meanwhile, the prepared ZnO/TiO2 photocatalytic film exhibited favorable stability of 95.5% degradation efficiency after the fourth run and general applicability for the photodegradation of various contantains, whih removed 99.5% of ofloxacin (OFX) and 77.6% of tetracycline (TC) in 2 h and 94.1% of Rhodamine B (RhB) in 1 h. This work is expected to yields a novel insight into the production of heterojunction photocatalysts with excellen ability for photocatalytic degradation of pollutants in the practical industry.

Ultrasonically functionalized chitosan-gallic acid films inactivate Staphylococcus aureus through envelope-disruption under UVA light exposure

The significant threat of foodborne pathogens contamination has continuously promoted the development of efficient antimicrobial food packaging materials. Here, an antimicrobial film was prepared with gallic acid-grafted-chitosan (CS/GA) that obtained by a two-step ultrasound method. The resultant films exhibited good transparency, improved UV barrier performance, and enhanced mechanical strength. Specifically, with the grafting of 1.2 % GA, the UV blocking ability of CS/GA film at 400 nm was significantly increased by 19.7 % and the tensile strength was nearly two times higher than that of CS film. Moreover, the CS/GA films exhibited an inspiring photoactivated bactericidal ability under 400 nm UVA light irradiation that eradicated almost 99.9 % of Staphylococcus aureus (S. aureus) cells within 60 min. To gain more insights into the antibacterial mechanism, the treated S. aureus cells were further investigated by visualizing bacterial ultrastructure and analyzing membrane properties. The results pointed to the peptidoglycan layer as the primary action target when bacteria come into contact with CS/GA films. Afterward, the intracellular oxidative lesions, disrupted bacterial integrity, and disordered membrane functional properties collectively resulted in eventual cell death. The findings revealed the unique peptidoglycan targeting and membrane disruptive mechanisms of CS/GA films, confirming the application values in controlling foodborne pathogens.

Study on the correlation between dietary structure and sleep in patients with insomnia disorder

OBJECTIVE

Insomnia disorder (ID) is a persistent difficulty sleeping, often accompanied by anxiety and depression, which seriously reduces a person's quality of life. Dietary changes in insomnia patients have been a concern. To explore the rationality of diet in patients with ID and its correlation with insomnia in ID patients.

PATIENTS AND METHODS

This study included 216 patients diagnosed with ID and 197 individuals as the healthy control (HC) group who attended the neurology outpatient clinic or sleep clinic at Henan Provincial People's Hospital between September 2018 and November 2019. Through the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD), sleep and mental conditions were assessed in the ID and HC groups. The dietary intake structure of both groups was observed using the food frequency table. Meanwhile, the relationship between dietary intake and sleep quality was analyzed based on the logistics regression.

RESULTS

Individuals in the ID group had significantly higher age, weight, and body mass index compared to the HC group (p<0.01). Individuals within the ID category demonstrated a heightened daily consumption of carbohydrates, grains, tubers, and legumes relative to the healthy control group. In contrast, the intake levels of vegetables, fruits, and nuts were diminished compared to the HC group, with this difference being statistically significant (p<0.01). A positive correlation was observed between the daily consumption of grains, tubers, and legumes and PSQI scores. Conversely, a negative association was found between daily consumption of vegetables and fruits.

CONCLUSIONS

ID patients exhibit an elevated intake of carbohydrates, whereas the consumption of vegetables, fruits, and nuts is deficient in comparison to the healthy cohort, implying that a distorted dietary structure might be a contributing factor to ID onset. Sensible and scientific dietary guidance is of considerable significance in preventing the onset of ID and facilitating its management. However, the derived conclusions warrant further extensive research.

Standard Therapy vs. Individualized Therapy in Elderly Locally Advanced Nasopharyngeal Carcinoma: A Real-World Study

PURPOSE/OBJECTIVE(S)

Concurrent chemoradiotherapy (CRT) with/without induction chemotherapy has been the standard therapy (ST) for locally advanced nasopharyngeal carcinoma (LA-NPC). However, most patients supporting these clinical trials were younger than 65 years of age. For the toxicity of CRT and the poor tolerance of elderly patients, it is still controversial whether ST could bring the most promising survival benefits for elderly NPC compared with individualized therapy (IT). Thus, in this real-world study we compared the survival and safety of ST with IT in elderly LA-NPC to explore an effective and tolerable treatment strategy for elderly LA-NPC.

MATERIALS/METHODS

A total of 109 newly diagnosed elderly LA-NPC (>65 years old) from Jan. 2013-Jul. 2020 were retrospectively enrolled and divided into the ST group and IT group according to the original treatment tendency. ST refers to CRT with/without induction chemotherapy. IT group included patients not suitable for CRT and were given individualized treatment fully discussed by at least two oncologists from our head and neck team. A 1:1 propensity score matching (PSM) generated a matched cohort of ST and IT. The survivals and treatment related toxicities were compared between the two groups.

RESULTS

There were 46 cases in the ST group and 63 cases in the IT group. The 5-year overall survival (OS) rate, cancer-specific survival (CSS) rate, progression- free survival (PFS) rate, local recurrence-free survival (LRFS) rate and distant metastasis-free survival (DMFS) rate were 68.64%, 76.42%, 73.69%, 85.67% and 86.82%, respectively. By 1:1PSM, 35 cases in each group were matched. No significant differences of OS, CSS, PFS, LRFS and DMFS were found between ST and IT groups in the PSM-matched cohorts (P = 0.87, P = 0.79, P = 0.51, P = 0.81 and P = 0.24, respectively). Compared with patients in the ST group, cases received IT were associated with less severe acute toxicities including anemia, leucopenia, neutropenia, and thrombocytopenia.

CONCLUSION

For elderly LA-NPC, IT had similar survivals while less severe toxicities compared with ST, which revolutionarily challenged the role of ST for elderly LA-NPC. In the future, more studies are need to explore a less toxic treatment modality with noninferior efficacy for elderly LA-NPC.

Data correction and verification of thermal simulation experiments under the influence of bulging belly

During the thermal simulation compression test, the formation of an obvious bulge in the specimen leads to a certain deviation between the calculated and actual values of the true stress. The finite element method was used to simulate the single-pass compression of specimens of 34CrNi3MoV steel and obtain the actual nonuniform deformation of the bulging belly during the compression process, and the results were applied to correct experimental flow curves. The results showed that the deformation conditions had a significant influence on the nonuniformity of the specimen deformation during the compression process, and all the modified flow curves were lower than the original ones. The size of the bulge and the metal flow line in the finite element simulation were consistent with the test results. The load value obtained by using the modified flow curve was similar to the load value measured in the test, which indicated that the modified flow curve was very close to the real flow force curve of the material. The method used to modify the flow force curve is simple and practical.

Exosome Release Delays Senescence by Disposing of Obsolete Biomolecules

Accumulation of obsolete biomolecules can accelerate cell senescence and organism aging. The two efficient intracellular systems, namely the ubiquitin-proteasome system and the autophagy-lysosome system, play important roles in dealing with cellular wastes. However, how multicellular organisms orchestrate the processing of obsolete molecules and delay aging remains unclear. Herein, it is shown that prevention of exosome release by GW4869 or Rab27a^-/- accelerated senescence in various cells and mice, while stimulating exosome release by nutrient restriction delays aging. Interestingly, exosomes isolate from serum-deprived cells or diet-restricted human plasma, enriched with garbage biomolecules, including misfolded proteins, oxidized lipids, and proteins. These cellular wastes can be englobed by macrophages, eventually, for disintegration in vivo. Inhibition of nutrient-sensing mTORC1 signaling increases exosome release and delays senescence, while constitutive activation of mTORC1 reduces exosome secretion and exacerbates senescence in vitro and in mice. Notably, inhibition of exosome release attenuates nutrient restriction- or rapamycin-delayed senescence, supporting a key role for exosome secretion in this process. This study reveals a potential mechanism by which stimulated exosome release delays aging in multicellular organisms, by orchestrating the harmful biomolecules disposal via exosomes and macrophages.

Temperature management of intraoperative cardiopulmonary bypass in valve replacement surgery: a retrospective analysis of the impact on postoperative organ function

OBJECTIVE

This study aimed to systematically analyze the effects of cardiopulmonary bypass (CPB) at different temperatures on the function of different organs in patients after heart valve replacement and to investigate its safety and feasibility.

PATIENTS AND METHODS

The data of 275 heart valve replacement surgery patients who underwent static suction compound anesthesia under CPB between February 2018 and October 2019 were retrospectively analyzed and divided into normothermic CPB anesthesia group (group 0), shallow hypothermic CPB anesthesia group (group 1), medium hypothermic CPB anesthesia group (group 2), and deep hypothermic CPB anesthesia group (group 3) according to the different intraoperative CPB temperatures. The basic preoperative conditions, cardiac resuscitation, number of defibrillations, postoperative ICU stay, postoperative hospital stay, and postoperative evaluation of different organ functions, such as heart, lung, and kidney functions, were analyzed and studied in each group.

RESULTS

The comparison of preoperative and postoperative pulmonary artery pressure and left ventricular internal diameter (LVD) was statistically significant in each group (p < 0.05), and the postoperative pulmonary function pressure was statistically significant in group 0 compared with groups 1 and 2 (p < 0.05). The preoperative glomerular filtration rate (eGFR) and the eGFR on the first postoperative day were statistically significant in all the groups (p < 0.05), and the eGFR on the first postoperative day in groups 1 and 2 were statistically significant (p < 0.05).

CONCLUSIONS

The control of appropriate temperature during CPB was associated with the recovery of organ function in patients after valve replacement. Intravenous compound general anesthesia with superficial hypothermic CPB might be more beneficial in recovering cardiac, pulmonary, and renal functions.

Combating Escherichia coli O157:H7 with Functionalized Chickpea-Derived Antimicrobial Peptides

The rapid dissemination of antibiotic resistance accelerates the desire for new antibacterial agents. Here, a class of antimicrobial peptides (AMPs) is designed by modifying the structural parameters of a natural chickpea-derived AMP-Leg2, termed "functionalized chickpea-derived Leg2 antimicrobial peptides" (FCLAPs). Among the FCLAPs, KTA and KTR show superior antibacterial efficacy against the foodborne pathogen Escherichia coli (E. coli) O157:H7 (with MICs in the range of 2.5-4.7 µmol L^-1 ) and demonstrate satisfactory feasibility in alleviating E. coli O157:H7-induced intestinal infection. Additionally, the low cytotoxicity along with insusceptibility to antimicrobial resistance increases the potential of FCLAPs as appealing antimicrobials. Combining the multi-omics profiling andpeptide-membrane interaction assays, a unique dual-targeting mode of action is characterized. To specify the antibacterial mechanism, microscopical observations, membrane-related physicochemical properties studies, and mass spectrometry assays are further performed. Data indicate that KTA and KTR induce membrane damage by initially targeting the lipopolysaccharide (LPS), thus promoting the peptides to traverse the outer membrane. Subsequently, the peptides intercalate into the peptidoglycan (PGN) layer, blocking its synthesis, and causing a collapse of membrane structure. These findings altogether imply the great potential of KTA and KTR as promising antibacterial candidates in combating the growing threat of E. coli O157:H7.

[microRNA let-7g-3p regulates proliferation, migration, invasion and apoptosis of bladder cancer cells by targeting HMGB2]

OBJECTIVE

To explore the molecular mechanism by which microRNA let-7g-3p regulates biological behaviors of bladder cancer cells.

METHODS

The expression levels of let-7g-3p in bladder cancer and adjacent tissues, normal bladder epithelial cells (HUC cells) and bladder cancer cells (T24, 5637 and EJ cells) were detected using qRT- PCR. T24 cells were transfected with let-7g-3p mimic or inhibitor, and the changes in cell proliferation, migration, invasion, and apoptosis were examined. Transcriptome sequencing was carried out in cells overexpressing let-7g-3p, and the results of bioinformatics analysis, double luciferase reporter gene assay, qRT-PCR and Western blotting confirmed that HMGB2 gene was the target gene of let-7g-3p. The expression of HMGB2 was examined in HUC, T24, 5637 and EJ cells, and in cells with HMGB2 knockdown, the effect of let-7g-3p knockdown on the biological behaviors were observed.

RESULTS

qRT-qPCR confirmed that let-7g-3p expression was significantly lower in bladder cancer tissues and cells (P < 0.01). Overexpression of let-7g-3p inhibited cell proliferation, migration and invasion, and promoted cell apoptosis, while let-7g-3p knock-down produced the opposite effects. Bioinformatics and transcriptome sequencing results showed that HMGB2 was the key molecule that mediate the effect of let-7g-3p on bladder cancer cells. Luciferase reporter gene assay, qRT-PCR and Western blotting all confirmed that HMGB2 was negatively regulated by let-7g-3p (P < 0.01). Knocking down HMGB2 could partially reverse the effect of let-7g-3p knockdown on the biological behaviors of the bladder cancer cells.

CONCLUSION

The microRNA let-7g-3p can inhibit the biological behavior of bladder cancer cells by negatively regulating HMGB2 gene.

Deletion of Rheb1 in Osteocytes Leads to Osteopenia Characterized by Reduced Bone Formation and Enhanced Bone Resorption

Ras homologue enriched in brain 1 (Rheb1), an upstream activator of the mechanistic target of rapamycin complex 1 (mTORC1), is known to modulate various cellular processes. However, its impact on bone metabolism in vivo remains unknown. The study aimed at understanding the role of Rheb1 on bone homeostasis. We measured the serum parameters and performed histomorphometry, quantitative real-time polymerase chain reaction, and Western blotting, along with the generation of mouse gene knockout (KO) model, and conducted a microcomputed tomography analysis and tartrate-resistant acid phosphatase staining, to delineate the impacts of Rheb1 on bone homeostasis. In the Rheb1 KO mice, the results showed that Rheb1 KO caused significant damage to the bone microarchitecture, indicating that mTORC1 activity was essential for the regulation of bone homeostasis. Specifically, suppressed mineralization activity in primary osteoblasts and a decreased osteoblast number were observed in the Rheb1 KO mice, demonstrating that loss of Rheb1 led to impaired osteoblastic differentiation. Furthermore, the higher apoptotic ratio in Rheb1-null osteocytes could promote Tnfsf11 expression and lead to an increase in osteoclasts, indicating increased bone resorption activity in the KO mice. The findings confirmed that Rheb1 deletion in osteoblasts/osteocytes led to osteopenia due to impaired bone formation and enhanced bone resorption.

DNMT1 is a negative regulator of osteogenesis

The role and underlying mechanisms of DNA methylation in osteogenesis/chondrogenesis remain poorly understood. We here reveal DNA methyltransferase 1 (DNMT1), which is responsible for copying DNA methylation onto the newly synthesized DNA strand after DNA replication, is overexpressed in sponge bone of people and mice with senile osteoporosis and required for suppression of osteoblast (OB) differentiation of mesenchymal stem cells (MSCs) and osteoprogenitors. Depletion of DNMT1 results in demethylation at the promoters of key osteogenic genes such as RORA and Fgfr2, and consequent upregulation of their transcription in vitro. Mechanistically, DNMT1 binds exactly to the promoters of these genes and are responsible for their 5-mc methylation. Conversely, simultaneous depletion of RORA or Fgfr2 blunts the effects of DNMT1 silencing on OB differentiation, suggesting RORA or Fgfr2 may be crucial for modulating osteogenic differentiation downstream of DNMT1. Collectively, these results reveal DNMT1 as a key repressor of OB differentiation and bone formation while providing us a new rationale for specific inhibition of DNMT1 as a potential therapeutic strategy to treat age-related bone loss.

Summary: DNMT1 is overexpressed in sponge bone of people and mice with senile osteoporosis and required for suppression of osteoblast (OB) differentiation of mesenchymal stem cells (MSCs) and osteoprogenitors.

Anti-inflammatory activity of peptides derived from millet bran in vitro and in vivo

Various food-derived bioactive peptides have been found with potential anti-inflammatory effects. Millet bran peptide is a food-derived bioactive peptide extracted from millet bran, a by-product of millet processing. In this...

Associations between severe pulmonary function and residual CT abnormalities in rehabilitating COVID-19 patients

OBJECTIVE

Coronavirus disease 2019 (COVID-19) spread around the world in 2020. Abnormal pulmonary function and residual CT abnormalities were observed in COVID-19 patients during recovery. Appropriate rehabilitation training is around the corner. The correlation between spirometric impairment and residual CT abnormality remains largely unknown.

PATIENTS AND METHODS

A cross-sectional study conducted on the pulmonary function of 101 convalescent COVID-19 patients before discharge. Multivariate analysis was used to establish a scoring system to evaluate the spirometric abnormality based on residual chest CT.

RESULTS

Lung consolidation area >25% and severe-type COVID-19 were two independent risk factors for severe pulmonary dysfunction. Besides, a scoring system was established. People scoring more than 12 points have more chances (17 times) to get severe pulmonary function impairment before discharge.

CONCLUSIONS

For the first time, a chest CT characteristics-based grading system was suggested to predict the pulmonary dysfunction of COVID-19 patients during convalescence in this study. This study may provide suggestions for pulmonary rehabilitation.

Damaged brain accelerates bone healing by releasing small extracellular vesicles that target osteoprogenitors

Clinical evidence has established that concomitant traumatic brain injury (TBI) accelerates bone healing, but the underlying mechanism is unclear. This study shows that after TBI, injured neurons, mainly those in the hippocampus, release osteogenic microRNA (miRNA)-enriched small extracellular vesicles (sEVs), which targeted osteoprogenitors in bone to stimulate bone formation. We show that miR-328a-3p and miR-150-5p, enriched in the sEVs after TBI, promote osteogenesis by directly targeting the 3'UTR of FOXO4 or CBL, respectively, and hydrogel carrying miR-328a-3p-containing sEVs efficiently repaires bone defects in rats. Importantly, increased fibronectin expression on sEVs surface contributes to targeting of osteoprogenitors in bone by TBI sEVs, thereby implying that modification of the sEVs surface fibronectin could be used in bone-targeted drug delivery. Together, our work unveils a role of central regulation in bone formation and a clear link between injured neurons and osteogenitors, both in animals and clinical settings.

[Modulatory effect of 2-arachidonoylglycerol on voltage-gated sodium currents in rat caudate nucleus neurons with kainic acid-induced injury]

OBJECTIVE

To investigate the modulatory effect of 2-arachidonoylglycerol (2-AG) on voltage-gated sodium currents(VGSCs) in rat caudate nucleus (CN) neurons with kainic acid (KA)-induced injury and explore the molecular mechanism underlying the neuroprotective effect of 2-AG.

METHODS

Primary cultures of CN neurons isolated from neonatal SD rats were treated with KA, 2-AG+KA, RIM (a CB1 receptor antagonist) +2-AG+KA, or vehicle only (as control).After 7 days in primary culture, the neurons were treated with corresponding agents for 12 h (RIM and 2-AG were added at the same time; KA was added 30 min later) before recording of current density changes, current-voltage characteristics, activation and inactivation kinetics of VGSCs (I_Na) using whole-cell patch clamp technique.

RESULTS

In cultured CN neurons, KA significantly increased current density of VGSCs (P=0.009) as compared with vehicle treatment.KA also produced a hyperpolarizing shift in the activation curve of I_Na and significantly increased the absolute value of V_1/2 for activation (P=0.008).Addition of 2-AG in the culture medium obviously prevented KA-induced increase of I_Na (P=0.009) and hyperpolarizing shift in the activation curve of I_Na, and significantly reduced the value of V_1/2 for activation(P=0.009)in a CB1 receptor-dependent manner.2-AG alone did not affect the density, activation or deactivation of VGSCs in rat CN neurons.

CONCLUSION

In excitotoxic events, endogenous 2-AG can offer neuroprotection by modulating VGSCs in the CN neurons through a CB1 receptor-dependent pathway.

Whole exome sequencing in molecular diagnostics of cancer decreases over time: evidence from a cost analysis in the French setting

OBJECTIVES

Although high-throughput sequencing is revolutionising medicine, data on the actual cost of whole exome sequencing (WES) applications are needed. We aimed at assessing the cost of WES at a French cancer institute in 2015 and 2018.

METHODS

Actual costs of WES application in oncology research were determined using both micro-costing and gross-costing for the years 2015 and 2018, before and after the acquisition of a new sequencer. The entire workflow process of a WES test was tracked, and the number and unit price of each resource were identified at the most detailed level, from library preparation to bioinformatics analyses. In addition, we conducted an ad hoc analysis of the bioinformatics storage costs of data issued from WES analyses.

RESULTS

The cost of WES has decreased substantially, from €1921 per sample (i.e. cost of €3842 per patient) in 2015 to €804 per sample (i.e. cost of €1,608 per patient) in 2018, representing a decrease of 58%. In the meantime, the cost of bioinformatics storage has increased from €19,836 to €200,711.

CONCLUSION

This study suggests that WES cost has decreased significantly in recent years. WES has become affordable, even though clinical utility and efficiency still need to be confirmed.

Vangl2 limits chaperone-mediated autophagy to balance osteogenic differentiation in mesenchymal stem cells

Lysosomes are the recycling center and nutrient signaling hub of the cell. Here, we show that lysosomes also control mesenchymal stem cell (MSC) differentiation by proteomic reprogramming. The chaperone-mediated autophagy (CMA) lysosome subgroup promotes osteogenesis, while suppressing adipogenesis, by selectively removing osteogenesis-deterring factors, especially master transcriptional factors, such as adipogenic TLE3, ZNF423, and chondrogenic SOX9. The activity of the CMA-committed lysosomes in MSCs are controlled by Van-Gogh-like 2 (Vangl2) at lysosomes. Vangl2 directly binds to lysosome-associated membrane protein 2A (LAMP-2A) and targets it for degradation. MSC-specific Vangl2 ablation in mice increases LAMP-2A expression and CMA-lysosome numbers, promoting bone formation while reducing marrow fat. The Vangl2:LAMP-2A ratio in MSCs correlates inversely with the capacity of the cells for osteoblastic differentiation in humans and mice. These findings demonstrate a critical role for lysosomes in MSC lineage acquisition and establish Vangl2-LAMP-2A signaling as a critical control mechanism.

Analysis of the mTOR Interactome using SILAC technology revealed NICE-4 as a novel regulator of mTORC1 activity

The evolutionarily conserved mechanistic target of rapamycin (mTOR) forms two functionally distinct complexes, -the mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2)-which differ in their subunit composition. Although the function of mTORC1 has been studied extensively, the interaction between mTORC1 and the ubiquitin-proteasome system (UPS) remains unclear. To facilitate a thorough understanding of the mechanismby which UPS regulates mTORC1 activity, steady isotope labeling with amino acids in cell culture (SILAC) technology was used to screen for potential mTORC1-interacting UPS members. Fourteen previously unknown proteins bound to mTOR in HEK293 cells with a SILAC ratio (heavy/light, H/L) above 2, five of which are components of the UPS. Subsequent immunoprecipitation analysis confirmed that ubiquitin-relevant protein 2-like (UBAP2L, also known as NICE-4) binds to both mTOR and Raptor, but not Rictor, suggesting that NICE-4 specifically interacts with mTORC1, but not mTORC2. Interestingly, NICE-4 is essential for basic mTORC1 activity in both HeLa cancer cells and HEK293 cells. In addition, NICE-4 depletion markedly suppressed proliferation of both HeLa and HEK293 cells as well as survival of HeLa cells. Collectively, these results revealed the identity of novel mTOR-interacting UPS proteins and established NICE-4 as a critical UPS member that maintains mTORC1 activity.

Circ-DONSON promotes malignant progression of glioma through modulating FOXO3

OBJECTIVE

The aim of this study was to investigate the expression level of circ-DONSON in glioma and to explore its effect on glioma metastasis and the underlying mechanism.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine circ-DONSON expression in 40 paired glioma tumor tissues and adjacent tissues. Meanwhile, the relation between circ-DONSON level and clinical parameters of glioma and the prognosis of patients was analyzed. The expression of circ-DONSON in glioma cell lines was analyzed by qRT-PCR as well. In addition, circs-DONSON silencing model was constructed in glioma cell lines. Cell counting kit-8 (CCK-8), cell scratch, and transwell migration assays were performed to investigate the effect of circ-DONSON on biological functions of glioma cells. Finally, the interplay between FOXO3 and circ-DONSON was explored.

RESULTS

QRT-PCR results revealed that the expression level of circ-DONSON in glioma tumor tissues was remarkably higher than that of adjacent tissues, and the difference was statistically significant (p<0.05). Compared with patients with low expression of circ-DONSON, significantly higher prevalence of lymph node or distant metastasis and worse prognosis were observed in patients with high expression of circ-DONSON (p<0.05). The proliferation and migration abilities of glioma cells in circ-DONSON silenced group were remarkably suppressed when compared with NC group (p<0.05). Additionally, FOXO3 expression was remarkably down-regulated in glioma cell lines and tissues. FOXO3 expression was negatively correlated with circ-DONSON expression. In addition, cell reverse experiment demonstrated that circ-DONSON and FOXO3 can regulate each other, thereby together affecting the malignant progression of glioma.

CONCLUSIONS

Circ-DONSON was remarkably associated with lymph node or distant metastasis, as well as poor prognosis of patients with glioma. Furthermore, it promoted the metastasis of glioma cells via regulating FOXO3.

DEPTOR Prevents Osteoarthritis Development Via Interplay With TRC8 to Reduce Endoplasmic Reticulum Stress in Chondrocytes

Endoplasmic reticulum (ER) stress has been shown to promote chondrocyte apoptosis and osteoarthritis (OA) progression, but the precise mechanisms via which ER stress is modulated in OA remain unclear. Here we report that DEP domain-containing mTOR-interacting protein (DEPTOR) negatively regulated ER stress and OA development independent of mTOR signaling. DEPTOR is ubiquitinated in articular chondrocytes and its expression is markedly reduced along with OA progression. Deletion of DEPTOR in chondrocytes significantly promoted destabilized medial meniscus (DMM) surgery-induced OA development, whereas intra-articular injection of lentivirus-expressing DEPTOR delayed OA progression in mice. Proteomics analysis revealed that DEPTOR interplayed with TRC8, which promoted TRC8 auto-ubiquitination and degraded by the ubiquitin-proteasome system (UPS) in chondrocytes. Loss of DEPTOR led to TRC8 accumulation and excessive ER stress, with subsequent chondrocyte apoptosis and OA progression. Importantly, an inhibitor of ER stress eliminated chondrocyte DEPTOR deletion-exacerbated OA in mice. Together, these findings establish a novel mechanism essential for OA pathogenesis, where decreasing DEPTOR in chondrocytes during OA progression relieves the auto-ubiquitination of TRC8, resulting in TRC8 accumulation, excessive ER stress, and OA progression. Targeting this pathway has promising therapeutic potential for OA treatment. © 2020 American Society for Bone and Mineral Research (ASBMR).

Discharge of a silo through a lateral orifice: Role of the bottom inclination versus friction

In this work we propose to identify the relative role of the inclination of gravitational acceleration and friction on the discharge flow rate of a granular media from a rectangular silo by varying the silo geometry thanks to an inclined bottom which ends up at a lateral outlet. The study is motivated by a nuclear safety problem: a fuel rod (modeled by an elongated silo) accidentally releases fuel fragments (modeled by grains). We performed experiments where we independently measured the mass flow rate and the velocity profiles, together with discrete particle simulations and continuum simulations with a frictional rheology described by a μ(I) constitutive law and taking into account the wall friction. We study monolayer flows and three-dimensional flows, and we propose an analytical model that predicts the discharge flow rate of particles from a rectangular silo with an inclined bottom according to its outlet aspect ratio and the bottom inclination angle.

Osteocyte TSC1 promotes sclerostin secretion to restrain osteogenesis in mice

Osteocytes secrete the glycoprotein sclerostin to inhibit bone formation by osteoblasts, but how sclerostin production is regulated in osteocytes remains unclear. Here, we show that tuberous sclerosis complex 1 (TSC1) in osteocytes promotes sclerostin secretion through inhibition of mechanistic target of rapamycin complex 1 (mTORC1) and downregulation of Sirt1. We generated mice with DMP1-Cre-directed Tsc1 gene deletion (Tsc1 CKO) to constitutively activate mTORC1 in osteocytes. Although osteocyte TSC1 disruption increased RANKL expression and osteoclast formation, it markedly reduced sclerostin production in bone, resulting in severe osteosclerosis with enhanced bone formation in mice. Knockdown of TSC1 activated mTORC1 and decreased sclerostin, while rapamycin inhibited mTORC1 and increased sclerostin mRNA and protein expression levels in MLO-Y4 osteocyte-like cells. Furthermore, mechanical loading activated mTORC1 and prevented sclerostin expression in osteocytes. Mechanistically, TSC1 promotes sclerostin production and prevents osteogenesis through inhibition of mTORC1 and downregulation of Sirt1, a repressor of the sclerostin gene Sost. Our findings reveal a role of TSC1/mTORC1 signalling in the regulation of osteocyte sclerostin secretion and bone formation in response to mechanical loading in vitro. Targeting TSC1 represents a potential strategy to increase osteogenesis and prevent bone loss-related diseases.

[Efficacy comparison between robot-assisted and laparoscopic surgery for mid-low rectal cancer: a prospective randomized controlled trial]

Objective: To compare the short- and long-term outcomes of robot-assisted and laparoscopic radical resection for mid-low rectal cancer. Methods: A prospective randomized controlled trial was conducted. A total of 130 patients with mid-low rectal cancer (inclusion criteria: age > 18 or ≤80 years old; pathological diagnosis of rectal adenocarcinoma by colonoscopy; distance from tumor to the anal verge ≤12 cm; no distant metastasis; cT1-3N0-1 or ycT1-3 after neoadjuvant radiotherapy and chemotherapy; suitable for laparoscopic and robotic surgery) at the Department of Colorectal Surgery of the First Affiliated Hospital of Nanchang University from October 2016 to September 2018 were prospectively enrolled. According to computer-generated random number method, patients were randomly divided into the robot group (n=66) and laparoscopy group (n=64), and underwent robot-assisted surgery or laparoscopic surgery respectively. Clinicopathological data of all the patients were collected and analyzed. The demographic parameters, short- and long-term outcomes were compared between two groups. Results: One patient in robot group whose postoperative sample was diagnosed as rectal adenoma by pathology was excluded. There were no statistically significant differences in age, sex, BMI, ASA classification, distance from tumor to the anal verge, serum CEA level, CA199 level between two groups (all P>0.05). Operations were successfully performed in all the patients without conversion to open operation. Robotic surgery was found to be associated with less intraoperative blood loss than laparoscopic surgery [(73.4±49.7) ml vs. (119.1±65.7) ml, t=-4.461, P<0.001], while there were no statistically significant differences in surgical procedures, operation time, time to first flatus, time to first liquid intake, time to removal of catheter or postoperative hospital stay between two groups (all P>0.05). Besides, there was no significant difference in the morbidity of postoperative complication between two groups [10.8% (7/65) vs. 12.5 (8/64), χ(2)=4.342, P=0.720]. The median number of harvested lymph node in the robot group and the laparoscopy group was 15.7±6.2 and 13.8±6.1 (t=1.724, P=0.087). There were no significant differences between two groups in tumor sample length, distance between proximal and distal resection margin, integrity grade of TME specimen, number of positive lymph nodes, postoperative pathological stage and tumor differentiation (all P>0.05). The distal resection margin of samples in two groups was all negative. One case in the robot group was found to have positive circumferential resection margin. The median follow up was 24 (9 to 31) months. In the robot group and the laparoscopy group, the 2-year overall survival rate was 95.4% and 90.6% respectively; the 2-year disease-free survival rate was 90.8% and 85.9% respectively, whose differences were not significant (both P>0.05). Conclusion: Robot-assisted radical resection for mid-low rectal cancer can achieve similar short-term and long-term outcomes of laparoscopic resection, while robot-assisted surgery can decrease blood loss during operation, leading to more precise practice in minimally invasive surgery.

Antihypertensive and antioxidant activities of enzymatic wheat bran protein hydrolysates

Bioactive peptides from plant protein sources have been continuously identified as nutrient supplements for low toxicity but multiple physiological activities such as antihypertensive, antioxidant, and anti-inflammatory. In this study, wheat bran protein isolate was digested with alcalase to produce wheat bran protein hydrolysate (WPH) that was then separated into different peptide fractions (<1, 1-3, 3-5, and 5-10 kDa) by membrane ultrafiltration. WPH and the peptide fractions were evaluated for in vitro activities such as antioxidant, renin inhibition, and angiotensin-converting enzyme (ACE) inhibition. In addition, the blood pressure-lowering effects of WPH and the <1 kDa peptides were determined by oral administration to spontaneously hypertensive rats (SHRs). Results showed that the ACE and renin inhibitions were significantly (p < .05) higher for the <1 kDa fraction (84.25% ± 2.45%, 75.19% ± 1.75%, respectively) when compared to the WPH and >1 kDa fractions. The <1 kDa fraction also showed significantly (p < .05) higher oxygen radical antioxidant activity with 2044.73 ± 37.45 (μM TE/g protein) when compared to lower values obtained for the >1 kDa membrane fractions and WPH. Oral administration (100 mg/kg body weight) of the <1 kDa membrane fraction to SHRs resulted in a better decrease (-35 mmHg) in the systolic blood pressure when compared to the WPH (-20 mmHg) after 6 hr. And seven peptides (NL, QL, FL, HAL, AAVL, AKTVF, and TPLTR) were identified and amino acid sequence was determined by tandem mass spectrometry. We conclude that the WPH could be considered as a suitable natural antihypertensive and antioxidant resource. PRACTICAL APPLICATIONS: The results of the present study indicate that WPH and its ultrafiltration fractions possess potential as a source of antihypertensive and strong antioxidant peptides. It has been proved that wheat bran has a good blood pressure lowering and antioxidation and other biological activities, and the <1 kDa fraction showing high oxygen radical absorbance capacity level also has better in vitro ACE inhibition and renin-inhibitory activity. The higher antihypertensive efficiency of the <1 kDa fraction may be because the peptides can be better absorbed from the gastrointestinal tract or an increased ability to interact with the enzyme (ACE or renin) protein structure to change the active conformation and lead to decreased catalysis. The results of this study indicate that WPH, especially <1 kDa peptide, can be used as a component in formulating antihypertensive functional foods and nutraceuticals, thus improving the industrial production efficiency and bioavailability of wheat bran.

Raptor directs Sertoli cell cytoskeletal organization and polarity in the mouse testis

Sertoli cells (SCs) play a central role in testis development, and their normal number and functions are required for spermatogenesis. Although the canonical tuberous sclerosis complex-mammalian target of rapamycin complex 1(TSC-mTORC1) pathway is critical for testis development and spermatogenesis, the signaling mechanisms governing SC functions remain unclear. In this study, we generated two SC-specific mouse mutants using the Cre-LoxP system. Loss of Raptor (a key component of mTORC1) caused severe tubular degeneration in the neonatal testis and adult mice displayed azoospermia, while adult Rheb (an upstream activator for mTORC1) mutant mice had intact tubules and many sperm in their epididymides. Disruption of cytoskeletal organization, including actin, microtubules, and SC-intrinsic vimentin, was observed in Raptor but not Rheb mutant mice. We investigated the reasons for these different effects by whole-transcriptome sequencing, and found that expression of the tight junction adaptor protein cingulin was significantly reduced in Raptor mutant mice. The expression profile of cingulin was synchronous with the differentiation and cytoskeletal dynamics of SCs in control mice, but was disordered in Raptor mutant mice. Furthermore, activity of the small GTPase Rac1 was reduced and expression of the guanine exchange factor for Rac1, Asef, was decreased in Raptor but not Rheb mutant mice. Collectively, these findings establish novel functions of Raptor, independent of the canonical Rheb/mTORC1 pathway, in controlling cytoskeletal homeostasis and cell polarity in SCs, by affecting cingulin expression and Rac1 activity.

[Application of multiple nucleotide polymorphism analysis in chimerism detection after allogeneic hematopoietic stem cell transplantation]

目的

建立一种利用多核苷酸多态性高通量测序（MNPseq）分析异基因造血干细胞移植后嵌合状态的新方法，并探讨其可行性及优越性。

方法

筛选100个MNP片段，采用高通量测序技术，通过模拟嵌合样本和临床移植后样本，与STR法、融合基因定量检测和流式细胞术微小残留病检测进行对比，验证方法的准确性和敏感性。

结果

MNPseq的准确性和敏感性均优于STR法，其中敏感性为0.01%，较STR法敏感约100倍；MNPseq可以进一步区分STR完全嵌合的42份样本，且经Cutoff值校正后，与融合基因定量检测结果相关；MNPseq可以纠正因为影子峰所造成的STR法的假阳性，并且可以用于检测缺乏供者和（或）患者移植前信息的嵌合体标本。

结论

基于高通量测序的MNPseq分析是一种更加准确和敏感的嵌合体检测方法，而且解决了缺乏移植前信息无法检测嵌合体的问题，具有极高的临床应用价值。

miR-191 is involved in renal dysfunction in arsenic-exposed populations by regulating inflammatory response caused by arsenic from burning arsenic-contaminated coal

Chronic exposure to arsenic may result in the manifestation of damage in multiple organs or systems of the body. Arsenic-induced renal dysfunction has been determined, but their pathogenesis has not been fully examined. In this study, we measured the expression levels of miR-191 in plasma, the contents of pro-inflammatory (interleukin (IL)-6 and tumor necrosis factor alpha) and anti-inflammatory (IL-2 and transforming growth factor beta) cytokines, and renal dysfunction indicators (blood urea nitrogen, blood creatinine, uric acid, and cystatin C) in serum from control and arsenic poisoning populations and analyzed the relationship between the miR-191, cytokines, and renal dysfunction indicators. The results clearly show the alteration of miR-191 expression was significantly associated with arsenic-induced renal dysfunction. Overall, the association of miR-191, inflammatory response and renal dysfunction, is clearly supported by the current findings. In other words, miR-191 is involved in renal dysfunction in exposed populations by regulating inflammatory response caused by coal-burning arsenic. The study provides a scientific basis for further studies of the causes of the arsenic-induced renal dysfunction, the biological role of miR-191, and targeted prevention strategies.

Exosome Release Is Regulated by mTORC1

Exosomes are small membrane-bound vesicles released into extracellular spaces by many types of cells. These nanovesicles carry proteins, mRNA, and miRNA, and are involved in cell waste management and intercellular communication. In the present study, it is shown that exosome release, which leads to net loss of cellular membrane and protein content, is negatively regulated by mechanistic target of rapamycin complex 1 (mTORC1). It is found that in cells and animal models exosome release is inhibited by sustained activation of mTORC1, leading to intracellular accumulation of CD63-positive exosome precursors. Inhibition of mTORC1 by rapamycin or nutrient and growth factor deprivation stimulates exosome release, which occurs concomitantly with autophagy. The drug-stimulated release is blocked by siRNA-mediated downregulation of small GTPase Rab27A. Analysis of the cargo content in exosomes released from rapamycin-treated cells reveals that inhibition of mTORC1 does not significantly alter its majority protein and miRNA profiles. These observations demonstrate that exosome release, like autophagy, is negatively regulated by mTORC1 in response to changes in nutrient and growth factor conditions.

Colonic epithelial mTORC1 promotes ulcerative colitis through COX-2-mediated Th17 responses

The functional role of colonic epithelium in the pathogenesis of ulcerative colitis (UC) remains unclear. Here, we reveal a novel mechanism by which colonic epithelia recruit T helper-17 (Th17) cells during the onset of UC. mTOR complex 1 (mTORC1) was hyper-activated in colonic epithelia of UC mice. While colonic epithelial TSC1 (mTORC1 negative regulator) disruption induced constitutive mTORC1 activation in the colon epithelia and aggravated UC, RPTOR (essential mTORC1 component) depletion inactivated mTORC1 and ameliorated UC. TSC1 deficiency enhanced, whereas RPTOR ablation reduced the expression of cyclooxygenase 2 (COX-2), interleukin-1 (IL-1), IL-6, and IL-23, as well as Th17 infiltration in the colon. Importantly, inhibition of COX-2 reversed the elevation in the expression of these proinflammatory mediators induced by TSC1 deficiency, and subsequently reduced the symptoms and pathological characteristics of UC in mouse models. Mechanistically, mTORC1 activates COX-2 transcription via phosphorylating STAT3 and enhancing it's binding to the COX-2 promoter. Consistently, enhanced mTORC1 activity and COX2 expression, as well as strong positive correlation between each other, were observed in colonic epithelial tissues of UC patients. Collectively, our study demonstrates an essential role of epithelial mTORC1 in UC pathogenesis and establishes a novel link between colonic epithelium, Th17 responses, and UC development.

Loss of DEPTOR in renal tubules protects against cisplatin-induced acute kidney injury

DEP domain containing mTOR-interacting protein (DEPTOR) was originally identified as an in vivo dual inhibitor of mechanistic target of rapamycin (mTOR). It was recently reported to be involved in renal physiology and pathology in vitro; however, its detailed roles and mechanisms in vivo are completely unknown. We observed that DEPTOR expression in the kidney was markedly increased on day 3 after cisplatin treatment, at which time cell apoptosis peaked, implicating DEPTOR in cisplatin-induced acute kidney injury (AKI). We then used the Cre–LoxP system to generate mutant mice in which the DEPTOR gene was specifically deleted in the proximal tubule cells. DEPTOR deficiency did not alter the renal histology or functions in the saline-treated group, indicating that DEPTOR is not essential for kidney function under physiological conditions. Interestingly, DEPTOR deletion extensively preserved the renal histology and maintained the kidney functions after cisplatin treatment, suggesting that the absence of DEPTOR ameliorates cisplatin-induced AKI. Mechanistically, DEPTOR modulated p38 MAPK signaling and TNFα production in vivo and in vitro, rather than mTOR signaling, thus moderating the inflammatory response and cell apoptosis induced by cisplatin. Collectively, our findings demonstrate the roles and mechanisms of DEPTOR in the regulation of the renal physiology and pathology, and demonstrate that the loss of DEPTOR in the proximal tubules protects against cisplatin-induced AKI.