Spatholobus suberectus extract suppresses proliferation and EMT, and promotes apoptosis in palmitic acid induced vascular endothelial cells by inhibiting LncRNA MALAT1 via VEGF signaling pathway

Purpose: In type 2 diabetes, palmitic acid could damage vessels and induce insulin resistance. This present in vitro study evaluates the possible role of Spatholobus suberectus (FSS) extract in diabetes.Methods: Human HUVECc cells were treated with palmitic acid, palmitic acid and Spatholobus suberectus extract. MALAT1 overexpression plasmid (pcDNA-MALAT1) and blank vector were transfected into the cells using lipofectamine 2000. RT-qPCR assay was used to evaluated the expression changes of lncRNA, VEGFR2 and VEGFA in the cells as well as Epithelial-Mesenchymal Transition (EMT) biomarkers and apoptosis. CCK-8 was used to detect cell viabilities of HUVECs. Expressions of proteins in VEGF signaling pathway were analyzed using Western Blot.Results: LncRNA MALAT1 had high expression in diabetes-like cells and suppressed proliferation and EMT but promoted apoptosis. The SS extract promoted proliferation and EMT and repressed apoptosis in diabetes-like HUVECs cells. The promotion of apoptosis by LncRNA MALAT1, inhibition of apoptosis and regulated functions of diabetes-like HUVECs cells by SS extract occurred via the VEGF signaling pathwayConclusion: SS extract might contribute to survival of cells by inhibiting MALAT1 via VEGF signaling pathway in vitro, suggesting FSF might be a potential therapeutic agent in the treatment of diabetes. Keywords: flavone of Spatholobus suberectus, diabetes, vascular endothelial cell, LncRNA MALAT

Heteroepitaxial growth of ZnO branches selectively on TiO2 nanorod tips with improved light harvesting performance

A seeded heteroepitaxial growth of ZnO nanorods selectively on TiO2 nanorod tips was achieved by restricting crystal growth on highly hydrophobic TiO2 nanorod film surfaces. Intriguing light harvesting performance and efficient charge transport efficiency has been found, which suggest potential applications in photovoltaics and optoelectronics

DDX3 directly regulates TRAF3 ubiquitination and acts as a scaffold to coordinate assembly of signalling complexes downstream of MAVS

The human DEAD-box helicase 3 (DDX3) has been shown to contribute to type I interferon induction downstream of anti-viral pattern recognition receptors (PRRs). It binds to TANK-binding kinase 1 (TBK1) and IB-kinase- (IKK, the two key kinases mediating activation of Interferon regulatory factor (IRF) 3 and IRF7. We previously demonstrated that DDX3 facilitates IKK activation downstream of RIG-I and then links the activated kinase to IRF3. In this study, we probed the interactions between DDX3 and other key signalling molecules in the RIG-I pathway and identified a novel direct interaction between DDX3 and TRAF3 mediated by a TRAF-interaction motif in the N-terminus of DDX3, which was required for TRAF3 ubiquitination. Interestingly, we observed two waves of K63-linked TRAF3 ubiquitination following RIG-I activation by Sendai Virus infection (SeV), both of which were suppressed by DDX3 knockdown. We also investigated the spatiotemporal formation of endogenous downstream signalling complexes containing the MAVS adaptor, DDX3, IKK, TRAF3 and IRF3. DDX3 was recruited to MAVS early after SeV infection, suggesting it might mediate subsequent recruitment of other molecules. Indeed, knockdown of DDX3 prevented formation of TRAF3-MAVS and TRAF3-IKKcomplexes. Based on our data, we propose that early TRAF3 ubiquitination is required for formation of a stable MAVS-TRAF3 complex, while the second wave of TRAF3 ubiquitination mediates IRF3 recruitment and activation. Our study characterises DDX3 as a multifunctional adaptor molecule that coordinates assembly of different TRAF3, IKK and IRF3-containing signalling complexes downstream of MAVS. Additionally, it provides novel insights into the role of TRAF3 in RIG-I signalling

DDX3 directly regulates TRAF3 ubiquitination and acts as a scaffold to coordinate assembly of signalling complexes downstream of MAVS

The human DEAD-box helicase 3 (DDX3) has been shown to contribute to type I interferon induction downstream of anti-viral pattern recognition receptors (PRRs). It binds to TANK-binding kinase 1 (TBK1) and IB-kinase- (IKK, the two key kinases mediating activation of Interferon regulatory factor (IRF) 3 and IRF7. We previously demonstrated that DDX3 facilitates IKK activation downstream of RIG-I and then links the activated kinase to IRF3. In this study, we probed the interactions between DDX3 and other key signalling molecules in the RIG-I pathway and identified a novel direct interaction between DDX3 and TRAF3 mediated by a TRAF-interaction motif in the N-terminus of DDX3, which was required for TRAF3 ubiquitination. Interestingly, we observed two waves of K63-linked TRAF3 ubiquitination following RIG-I activation by Sendai Virus infection (SeV), both of which were suppressed by DDX3 knockdown. We also investigated the spatiotemporal formation of endogenous downstream signalling complexes containing the MAVS adaptor, DDX3, IKK, TRAF3 and IRF3. DDX3 was recruited to MAVS early after SeV infection, suggesting it might mediate subsequent recruitment of other molecules. Indeed, knockdown of DDX3 prevented formation of TRAF3-MAVS and TRAF3-IKKcomplexes. Based on our data, we propose that early TRAF3 ubiquitination is required for formation of a stable MAVS-TRAF3 complex, while the second wave of TRAF3 ubiquitination mediates IRF3 recruitment and activation. Our study characterises DDX3 as a multifunctional adaptor molecule that coordinates assembly of different TRAF3, IKK and IRF3-containing signalling complexes downstream of MAVS. Additionally, it provides novel insights into the role of TRAF3 in RIG-I signalling

Effects of different forms of nitrogen addition on microbial extracellular enzyme activity in temperate grassland soil

Funding Information: We want to thank the reviewers for their insightful comments towards improving the manuscript. We acknowledge the valuable help from all the staff of the Erguna Forest-Steppe Ecotone Ecosystem Research Station of IAE, CAS. Funding Information: The funding for this research was supported by the National Natural Science Foundation of China (32022054 and 31901137), and China Postdoctoral Science Foundation (2018M640263), Instrument Developing Project of CAS (YJKYYQ20190079), Strategic Priority Research Program of CAS (Grant No. XDA28120100) and Youth Innovation Promotion Association of CAS (2019198). Publisher Copyright: © 2022, The Author(s).Background: Nitrogen (N) deposition alters litter decomposition and soil carbon (C) sequestration by influencing the microbial community and its enzyme activity. Natural atmospheric N deposition comprises of inorganic N (IN) and organic N (ON) compounds. However, most studies have focused on IN and its effect on soil C cycling, whereas the effect of ON on microbial enzyme activity is poorly understood. Here we studied the effects of different forms of externally supplied N on soil enzyme activities related to decomposition in a temperate steppe. Ammonium nitrate was chosen as IN source, whereas urea and glycine were chosen as ON sources. Different ratios of IN to ON (Control, 10:0, 7:3, 5:5, 3:7, and 0:10) were mixed with equal total amounts of N and then used to fertilize the grassland soils for 6 years. Results: Our results show that IN deposition inhibited lignin-degrading enzyme activity, such as phenol oxidase (POX) and peroxidase (PER), which may restrain decomposition and thus induce accumulation of recalcitrant organic C in grassland soils. By contrast, deposition of ON and mixed ON and IN enhanced most of the C-degrading enzyme activities, which may promote the organic matter decomposition in grassland soils. In addition, the β-N-acetyl-glucosaminidase (NAG) activity was remarkably stimulated by fertilization with both IN and ON, maybe because of the elevated N availability and the lack of N limitation after long-term N fertilization at the grassland site. Meanwhile, differences in soil pH, soil dissolved organic carbon (DOC), and microbial biomass partially explained the differential effects on soil enzyme activity under different forms of N treatments. Conclusions: Our results emphasize the importance of organic N deposition in controlling soil processes, which are regulated by microbial enzyme activities, and may consequently change the ecological effect of N deposition. Thus, more ON deposition may promote the decomposition of soil organic matter thus converting C sequestration in grassland soils into a C source.Peer reviewe

N-acetylcysteine Protects against Apoptosis through Modulation of Group I Metabotropic Glutamate Receptor Activity

The activation of group I metabotropic glutamate receptor (group I mGlus) has been shown to produce neuroprotective or neurotoxic effects. In this study, we investigated the effects of N-acetylcysteine (NAC), a precursor of the antioxidant glutathione, on group I mGlus activation in apoptosis of glial C6 and MN9D cell lines, and a rat model of Parkinson's disease (PD). We demonstrated that NAC protected against apoptosis through modulation of group I mGlus activity. In glial C6 cells, NAC promoted phosphorylation of ERK induced by (s)-3,5- dihydroxy-phenylglycine (DHPG), an agonist of group I mGlus. NAC enhanced the group I mGlus-mediated protection from staurosporine (STS)-induced apoptosis following DHPG treatment. Moreover, in rotenone-treated MN9D cells and PD rat model, NAC protected against group I mGlus-induced toxicity by compromising the decrease in phosphorylation of ERK, phosphorylation or expression level of TH. Furthermore, the results showed that NAC prohibited the level of ROS and oxidation of cellular GSH/GSSG (Eh) accompanied by activated group I mGlus in the experimental models. Our results suggest that NAC might act as a regulator of group I mGlus-mediated activities in both neuroprotection and neurotoxicity via reducing the oxidative stress, eventually to protect cell survival. The study also suggests that NAC might be a potential therapeutics targeting for group I mGlus activation in the treatment of PD

A STUDY ON FOUR ANTIOXIDATION EFFECTS OF LYCIUM BARBARUM POLYSACCHARIDES IN VITRO

The objective of the study was to investigate the in vitro antioxidation activity of lycium barbarum polysaccharides (LBP). Ultraviolet spectrophotometry was adopted to determine the capability of LBP to clear superoxide anions, hydroxyl radicals, DPPH free radicals and ABTS free radicals. The result showed that the law for LBP to clear superoxide anions, hydroxyl radicals and DPPH free radicals was that the clearance rate increased gradually with the increase of the concentration, and when the concentration reached a certain value, the clearance rate leveled off, while the IC50 for clearing ABTS free radicals was 47.158±6.231μg/ml. The study concluded that LBP is a good in vitro antioxidant