No evidence of genetic causality between diabetes and osteonecrosis: a bidirectional two-sample Mendelian randomization analysis.

OBJECTIVE: This study aimed to examine whether diabetes mellitus is causally associated with osteonecrosis. METHOD: Using publicly accessible genome-wide association study statistics, a bidirectional two-sample Mendelian randomization analysis was carried out. In order to determine whether diabetes has a causal effect on osteonecrosis and whether osteonecrosis has a causal effect on diabetes, we extracted six date on diabetes in Europeans from IEU OpenGWAS and GWAS Catalogue and osteonecrosis in Europeans from FinnGen. We then evaluated the data using inverse variance weighting, MR-Egger regression, weighted median, weighted mode, and simple mode. The results' stability and dependability were then evaluated using sensitivity analysis and heterogeneity analysis. Finally, meta-analysis is used to further confirm if there is a relationship between diabetes and osteonecrosis. RESULTS: When diabetes was used as an exposure factor, MR-Egger regression showed that directional fold product was unlikely to bias the results. Cochran's Q test showed only minor heterogeneity in a few data sets. Multidirectional tests Egger-intercept, MR-PRESSO and funnel plots for most data did not show multidirectional and asymmetry at the gene level. Most of the IVW results showed no causal relationship between diabetes mellitus and osteonecrosis. The results of meta-analysis of IVW methods further confirmed the absence of a causal relationship. Inverse MR analysis also showed no causal relationship between osteonecrosis and diabetes. CONCLUSION: Results of bidirectional MR analysis show no evidence of causal relationship between diabetes and osteonecrosis.

Exploration of Antimicrobial Ingredients in Psoralea corylifolia L. Seed and Related Mechanism against Methicillin-Resistant Staphylococcus aureus.

With the abuse of antibiotics, bacterial antibiotic resistance is becoming a major public healthcare issue. Natural plants, especially traditional Chinese herbal medicines, which have antibacterial activity, are important sources for discovering potential bacteriostatic agents. This study aimed to develop a fast and reliable method for screening out antimicrobial compounds targeting the MRSA membrane from Psoralea corylifolia Linn. seed. A UPLC-MS/MS method was applied to identify the prenylated flavonoids in major fractions from the extracts of Psoralea corylifolia Linn. seed. The broth microdilution method was used to determine the minimum inhibitory concentrations (MICs) of different fractions and compounds. The morphological and ultrastructural changes of MRSA were determined by scanning electron microscopy (SEM). The membrane-targeting mechanism of the active ingredients was explored by membrane integrity assays, membrane fluidity assays, membrane potential assays, ATP, and ROS determination. We identified eight prenylated flavonoids in Psoralea corylifolia Linn. seed. The antibacterial activity and mechanism studies showed that this type of compound has a unique destructive effect on MRSA cell membranes and does not result in drug resistance. The results revealed that prenylated flavonoids in Psoralea corylifolia Linn. seeds are promising candidates for the development of novel antibiotic agents to combat MRSA-associated infections.

Anti-Respiratory Syncytial Virus Mechanism of Houttuynia cordata Thunb Exploration based on Network Pharmacology.

BACKGROUND AND OBJECTIVE: Respiratory Syncytial Virus (RSV) is the leading cause of infant lower respiratory tract infections with no mature vaccines and medicines available. Pneumonia caused by RSV kills many infants every year. There are unique advantages of Traditional Chinese Medicine (TCM) to fight against the virus. Houttuynia cordata Thunb is a commonly used antivirus medicine in TCM, but its mechanism has not been investigated. The current study explores the anti-RSV mechanism of H. cordata Thunb by means of network pharmacology and bioinformatics. METHODS: The candidate compounds of H. cordata Thunb and the potential targets were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), PubMed, CNKI, PubChem Database, and Swiss Target Prediction database. Then the potential targets and pathways of H. cordata Thunb against RSV were screened by GeneCards, GenCLiP 3, and NCBI Database. We developed a Protein-Protein Interactions (PPI) Network and Compound-Target-Pathway Network through the Cytoscape software. Furthermore, core targets were preliminary verified by Gene Expression Omnibus (GEO) database by bioinformatics methods. At last, the first six pathways were screened out to draw a map of the main target signal pathways. RESULTS: A total of 12 potentially active compounds and 47 potential interaction targets were screened. PPI Network and data from GEO showed that IL-6, STAT3, TNF, AKT1, PTGS2, SRC, and MAPK3 may play a core role in the antivirus process. KEGG enrichment pathway analysis predicted that H. cordata Thunb exerted its anti-RSV effect by regulating TNF, Rap1, HIF-1, PI3KAkt, MAPK, and VEGF signaling pathways. CONCLUSION: This study preliminarily predicted the main active compounds, targets and related pathways of H. cordata Thunb in the treatment of RSV-induced diseases, which laid a good foundation for further revealing its mechanism.

The Separation of Antler Polypeptide and Its Effects on the Proliferation and Osteogenetic Differentiation of Bone Marrow Mesenchymal Stem Cells.

BACKGROUND: Colla Cornus Cervi (CCC) has been used as a traditional Chinese medicine in the treatment of osteoporosis and osteonecrosis of the femoral head. However, the bioavailability of CCC is seriously limited owing to its large molecular weight and complex ingredients. In the present study, antler polypeptide was separated from CCC, and the effects of antler polypeptide on rat bone marrow mesenchymal stem cells (BMSCs) were investigated. METHODS: Antler polypeptide was separated from Colla Cornus Cervi by ultrafiltration into different samples according to the molecular weight. The total peptide content of these samples was determined by the biuret method. The content of antler polypeptide in different samples was quantified by high-performance liquid chromatography (HPLC). The effects of antler polypeptide at different concentrations on the proliferation, cell cycle, alkaline phosphatase activity, and BMP7 expression of BMSCs were investigated. RESULTS: Antler polypeptide was separated by ultrafiltration into different samples: A (molecular weight <800 Da), B (molecular weight 800-1500 Da), and C (molecular weight >1500 Da). The total peptide contents of A, B, and C were 0.602 mg/mL, 8.976 mg/mL, and 38.88 mg/mL. Antler polypeptide B eluted at 14.279∼15.351 min showed that the content of antler polypeptide was significantly higher than that of A and C with a peak area of 933.80927. The BMSCs proliferation rate (84.66%) of polypeptide B was the highest at the concentration of 1.578 × 10-2 g/mL. Antler polypeptide B significantly promoted the proliferation of BMSCs with a proliferation index of 38.68%, which was significantly higher than that of the other groups. Antler polypeptide B significantly enhanced the activity of alkaline phosphatase in BMSCs compared to that of the blank group (P < 0.001). Antler polypeptide B increased the BMP7 protein expression in BMSCs. CONCLUSIONS: Results suggested that antler polypeptide may promote the proliferation and osteogenic differentiation of BMSCs. Our study lays an experimental foundation for the further development and application of antler polypeptide in medicine.

Repair of osteonecrosis of the femoral head : 3D printed Cervi cornus Colla deproteinized bone scaffolds.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is a common joint disease and a major cause of morbidity. OBJECTIVE: In this study Cervi cornus Colla (CCC) deproteinized bone scaffolds were designed and three dimensional (3D)-printed for the repair of ONFH in rats. MATERIAL AND METHODS: The CCC-deproteinized bone scaffolds were 3D-printed using polycaprolactone mixed with the CCC-deproteinized bone powder. The scaffolds were viewed under a scanning electron microscope and subjected to compression analysis. Osteoblasts were isolated from rats and coated onto the scaffolds. Cell proliferation assays were performed with the MTT (3­[4,5-dimethylthiazole­2]-2,5-diphenyltetrazolium bromide) kit from Promega. An ONFH was induced in rats and a CCC-deproteinized bone scaffold was implanted into the necrotic femoral head. General observations, X­ray imaging, and pathological examination of the femoral head were performed to evaluate the treatment of ONFH in the rats. RESULTS: The scaffolds were porous with a mean pore diameter of 315.70 ± 41.52 nm and a porosity of 72.86 ± 5.45% and exhibited favorable mechanical properties and degradation. In vitro assays showed that osteoblasts accumulated in the pores and adhered to the scaffolds. The CCC-deproteinized bone scaffolds enhanced the proliferation of osteoblasts. The in vivo experiments revealed that the general observation score of rats in the CCC-scaffold implanted group was significantly higher than that in the control group. The X­ray images showed significant alleviation of ONFH in the CCC-deproteinized bone scaffold implanted rats. The femoral heads of rats in the treatment group showed less destruction or ossification of cartilage cells, few bone cement lines, very little necrosis or irregularities on the cartilage surface and only a small amount of inflammatory cell infiltration in the medullary cavity. CONCLUSION: These results suggest that CCC-deproteinized bone scaffold implants facilitated the repair of ONFH in rats. This research provides a new therapeutic approach for the repair of early and mid-term ONFH.

Regulation of Stomatal Immunity by Interdependent Functions of a Pathogen-Responsive MPK3/MPK6 Cascade and Abscisic Acid.

Activation of mitogen-activated protein kinases (MAPKs) is one of the earliest responses after plants sense an invading pathogen. Here, we show that MPK3 and MPK6, two Arabidopsis thaliana pathogen-responsive MAPKs, and their upstream MAPK kinases, MKK4 and MKK5, are essential to both stomatal and apoplastic immunity. Loss of function of MPK3 and MPK6, or their upstream MKK4 and MKK5, abolishes pathogen/microbe-associated molecular pattern- and pathogen-induced stomatal closure. Gain-of-function activation of MPK3/MPK6 induces stomatal closure independently of abscisic acid (ABA) biosynthesis and signaling. In contrast, exogenously applied organic acids such as malate or citrate are able to reverse the stomatal closure induced by MPK3/MPK6 activation. Gene expression analysis and in situ enzyme activity staining revealed that malate metabolism increases in guard cells after activation of MPK3/MPK6 or inoculation of pathogen. In addition, pathogen-induced malate metabolism requires functional MKK4/MKK5 and MPK3/MPK6. We propose that the pathogen-responsive MPK3/MPK6 cascade and ABA are two essential signaling pathways that control, respectively, the organic acid metabolism and ion channels, two main branches of osmotic regulation in guard cells that function interdependently to control stomatal opening/closure.

Pathogen-Responsive MPK3 and MPK6 Reprogram the Biosynthesis of Indole Glucosinolates and Their Derivatives in Arabidopsis Immunity.

Antimicrobial compounds have critical roles in plant immunity; for example, Arabidopsis thaliana and other crucifers deploy phytoalexins and glucosinolate derivatives in defense against pathogens. The pathogen-responsive MITOGEN-ACTIVATED PROTEIN KINASE3 (MPK3) and MPK6 have essential functions in the induction of camalexin, the major phytoalexin in Arabidopsis. In search of cyanide, a coproduct of ethylene and camalexin biosynthesis, we found that MPK3 and MPK6 also affect the accumulation of extracellular thiocyanate ion derived from the indole glucosinolate (IGS) pathway. Botrytis cinerea infection activates MPK3/MPK6, which promote indole-3-yl-methylglucosinolate (I3G) biosynthesis and its conversion to 4-methoxyindole-3-yl-methylglucosinolate (4MI3G). Gain- and loss-of-function analyses demonstrated that MPK3/MPK6 regulate the expression of MYB51 and MYB122, two key regulators of IGS biosynthesis, as well as CYP81F2 and IGMT1/IGMT2, which encode enzymes in the conversion of I3G to 4MI3G, through ETHYLENE RESPONSE FACTOR6 (ERF6), a substrate of MPK3/MPK6. Under the action of PENETRATION2 (PEN2), an atypical myrosinase, and PEN3, an ATP binding cassette transporter, 4MI3G is converted to extracellular unstable antimicrobial compounds, possibly isothiocyanates that can react with nucleophiles and release the stable thiocyanate ion. Recent studies demonstrated the importance of PEN2/PEN3-dependent IGS derivatives in plant immunity. Here, we report that MPK3/MPK6 and their substrate ERF6 promote the biosynthesis of IGSs and the conversion of I3G to 4MI3G, a target of PEN2/PEN3-dependent chemical defenses in plant immunity.

EFFECT OF COLLA CORNUS CERVI COMBINED WITH LV-MEDIATED BMP7 TRANSFECTED BMSCs ON ANFH IN RATS.

In the present study, we investigated the combined effect of Colla Comus Cervi (CCC) and BMP7-overexpressing bone marrow-derived mesenchymal stem cells (BMSCs) on osteogenic induction and the treatment of avascular necrosis of the femoral head (ANFH). BMSCs were isolated from rats. BMP7-overexpressing BMSCs were generated by lentiviral-mediated gene transduction. Cell proliferation, alkaline phosphatase (ALP) activity, osteogenesis related gene expression, osteocalcin levels, and calcified nodules were quantified and compared between four groups: untreated controls, BMSCs cultured with CCC complex medium, BMP7-overexpressing BMSCs, and BMP7-overexpressing BMSCs cultured with CCC complex medium (CCC+BMP7). CCC+BMP7 BMSCs showed higher proliferation rate. ALP activity and osteaocalcin content were significantly increased in CCC+BMP7 BMSCs. The osteogenesis related genes, COLI, and integrin-α2, -α5, and -ß1, were expressed significantly higher in CCC+BMP7 BMSCs. The number of calcified nodules in the CCC+BMP7 group was significantly higher than that in other groups. For in vivo assays, ANFH was induced in rats, and BMSCs were injected into the femoral head of the lower left extremity. In rats with induced ANFH, general observation scores of the CCC+BMP7 injected group were significantly higher than the model group. X-ray and microscopic observations revealed that ANFH was significantly improved and femoral head cells gradually recovered in rats treated with CCC+BMP7 BMSCs. Our results suggest that CCC+BMP7 significantly promote the proliferation and osteogenic differentiation of BMSCs in vitm. CCC+BMP7 BMSCs promote the ability of repairing ANFH in rats, providing a new therapeutic paradigm for the treatment of ANFH.

Role and interrelationship of Gα protein, hydrogen peroxide, and nitric oxide in ultraviolet B-induced stomatal closure in Arabidopsis leaves.

Heterotrimeric G proteins have been shown to transmit ultraviolet B (UV-B) signals in mammalian cells, but whether they also transmit UV-B signals in plant cells is not clear. In this paper, we report that 0.5 W m(-2) UV-B induces stomatal closure in Arabidopsis (Arabidopsis thaliana) by eliciting a cascade of intracellular signaling events including Gα protein, hydrogen peroxide (H2O2), and nitric oxide (NO). UV-B triggered a significant increase in H2O2 or NO levels associated with stomatal closure in the wild type, but these effects were abolished in the single and double mutants of AtrbohD and AtrbohF or in the Nia1 mutants, respectively. Furthermore, we found that UV-B-mediated H2O2 and NO generation are regulated by GPA1, the Gα-subunit of heterotrimeric G proteins. UV-B-dependent H2O2 and NO accumulation were nullified in gpa1 knockout mutants but enhanced by overexpression of a constitutively active form of GPA1 (cGα). In addition, exogenously applied H2O2 or NO rescued the defect in UV-B-mediated stomatal closure in gpa1 mutants, whereas cGα AtrbohD/AtrbohF and cGα nia1 constructs exhibited a similar response to AtrbohD/AtrbohF and Nia1, respectively. Finally, we demonstrated that Gα activation of NO production depends on H2O2. The mutants of AtrbohD and AtrbohF had impaired NO generation in response to UV-B, but UV-B-induced H2O2 accumulation was not impaired in Nia1. Moreover, exogenously applied NO rescued the defect in UV-B-mediated stomatal closure in the mutants of AtrbohD and AtrbohF. These findings establish a signaling pathway leading to UV-B-induced stomatal closure that involves GPA1-dependent activation of H2O2 production and subsequent Nia1-dependent NO accumulation.