Lignin bioconversion based on genome mining for ligninolytic genes in Erwinia billingiae QL-Z3.

BACKGROUND: Bioconversion of plant biomass into biofuels and bio-products produces large amounts of lignin. The aromatic biopolymers need to be degraded before being converted into value-added bio-products. Microbes can be environment-friendly and efficiently degrade lignin. Compared to fungi, bacteria have some advantages in lignin degradation, including broad tolerance to pH, temperature, and oxygen and the toolkit for genetic manipulation. RESULTS: Our previous study isolated a novel ligninolytic bacterial strain Erwinia billingiae QL-Z3. Under optimized conditions, its rate of lignin degradation was 25.24% at 1.5 g/L lignin as the sole carbon source. Whole genome sequencing revealed 4556 genes in the genome of QL-Z3. Among 4428 protein-coding genes are 139 CAZyme genes, including 54 glycoside hydrolase (GH) and 16 auxiliary activity (AA) genes. In addition, 74 genes encoding extracellular enzymes are potentially involved in lignin degradation. Real-time PCR quantification demonstrated that the expression of potential ligninolytic genes were significantly induced by lignin. 8 knock-out mutants and complementary strains were constructed. Disruption of the gene for ELAC_205 (laccase) as well as EDYP_48 (Dyp-type peroxidase), ESOD_1236 (superoxide dismutase), EDIO_858 (dioxygenase), EMON_3330 (monooxygenase), or EMCAT_3587 (manganese catalase) significantly reduced the lignin-degrading activity of QL-Z3 by 47-69%. Heterologously expressed and purified enzymes further confirmed their role in lignin degradation. Fourier transform infrared spectroscopy (FTIR) results indicated that the lignin structure was damaged, the benzene ring structure and groups of macromolecules were opened, and the chemical bond was broken under the action of six enzymes encoded by genes. The abundant enzymatic metabolic products by EDYP_48, ELAC_205 and ESOD_1236 were systematically analyzed via liquid chromatography-mass spectrometry (LC-MS) analysis, and then provide a speculative pathway for lignin biodegradation. Finally, The activities of ligninolytic enzymes from fermentation supernatant, namely, LiP, MnP and Lac were 367.50 U/L, 839.50 U/L, and 219.00 U/L by orthogonal optimization. CONCLUSIONS: Our findings provide that QL-Z3 and its enzymes have the potential for industrial application and hold great promise for the bioconversion of lignin into bioproducts in lignin valorization.

To explore the effect of kaempferol on non-small cell lung cancer based on network pharmacology and molecular docking.

Non-small cell lung cancer (NSCLC) is a common pathological type of lung cancer, which has a serious impact on human life, health, psychology and life. At present, chemotherapy, targeted therapy and other methods commonly used in clinic are prone to drug resistance and toxic side effects. Natural extracts of traditional Chinese medicine (TCM) have attracted wide attention in cancer treatment because of their small toxic and side effects. Kaempferol is a flavonoid from natural plants, which has been proved to have anticancer properties in many cancers such as lung cancer, but the exact molecular mechanism is still unclear. Therefore, on the basis of in vitro experiments, we used network pharmacology and molecular docking methods to study the potential mechanism of kaempferol in the treatment of non-small cell lung cancer. The target of kaempferol was obtained from the public database (PharmMapper, Swiss target prediction), and the target of non-small cell lung cancer was obtained from the disease database (Genecards and TTD). At the same time, we collected gene chips GSE32863 and GSE75037 in conjunction with GEO database to obtain differential genes. By drawing Venn diagram, we get the intersection target of kaempferol and NSCLC. Through enrichment analysis, PI3K/AKT is identified as the possible key signal pathway. PIK3R1, AKT1, EGFR and IGF1R were selected as key targets by topological analysis and molecular docking, and the four key genes were further verified by analyzing the gene and protein expression of key targets. These findings provide a direction for further research of kaempferol in the treatment of NSCLC.

Selenium-modified bone cement promotes osteoporotic bone defect repair in ovariectomized rats by restoring GPx1-mediated mitochondrial antioxidant functions.

Over-accumulation of reactive oxygen species (ROS) causes mitochondrial dysfunction and impairs the osteogenic potential of bone marrow-derived mesenchymal stem cells (BMMSCs). Selenium (Se) protects BMMSCs from oxidative stress-induced damage; however, it is unknown whether Se supplementation can promote the repair of osteoporotic bone defects by rescuing the impaired osteogenic potential of osteoporotic BMMSCs (OP-BMMSCs). In vitro treatment with sodium selenite (Na2SeO3) successfully improved the osteogenic differentiation of OP-BMMSCs, as demonstrated by increased matrix mineralization and up-regulated osteogenic genes expression. More importantly, Na2SeO3 restored the impaired mitochondrial functions of OP-BMMSCs, significantly up-regulated glutathione peroxidase 1 (GPx1) expression and attenuated the intracellular ROS and mitochondrial superoxide. Silencing of Gpx1 completely abrogated the protective effects of Na2SeO3 on mitochondrial functions of OP-BMMSCs, suggesting the important role of GPx1 in protecting OP-BMMSCs from oxidative stress. We further fabricated Se-modified bone cement based on silk fibroin and calcium phosphate cement (SF/CPC). After 8 weeks of implantation, Se-modified bone cement significantly promoted bone defect repair, evidenced by the increased new bone tissue formation and enhanced GPx1 expression in ovariectomized rats. These findings revealed that Se supplementation rescued mitochondrial functions of OP-BMMSCs through activation of the GPx1-mediated antioxidant pathway, and more importantly, supplementation with Se in SF/CPC accelerated bone regeneration in ovariectomized rats, representing a novel strategy for treating osteoporotic bone fractures or defects.

Anticancer effects and mechanisms of astragaloside­IV (Review).

Astragalus membranaceus Bunge is widely used in Traditional Chinese Medicine to treat various cancers. Astragaloside­IV (AS­IV) is one of the major compounds isolated from A. membranaceus Bunge and has been demonstrated to have antitumor effects by inhibiting cell proliferation, invasion and metastasis in various cancer types. Numerous studies have used in vitro cell culture and in vivo animal models of cancer to explore the antitumor activities of AS­IV. In the present study, the antitumor effects and mechanisms of AS­IV reported in studies recorded in the PubMed database were reviewed. First, the antitumor effects of AS­IV on proliferation, cell cycle, apoptosis, autophagy, invasion, migration, metastasis and epithelial­mesenchymal transition processes in cancer cells and the tumor microenvironment, including angiogenesis, tumor immunity and macrophage­related immune responses to cancer cells, were comprehensively discussed. Subsequently, the molecular mechanisms and related signaling pathways associated with antitumor effects of AS­IV as indicated by in vitro and in vivo studies were summarized, including the Wnt/AKT/GSK-3ß (glycogen synthase kinase­3ß)/ß­catenin, TGF­ß/PI3K/AKT/mTOR, PI3K/MAPK/mTOR, PI3K/AKT/NF­κB, Rac family small GTPase 1/RAS/MAPK/ERK, TNF­α/protein kinase C/ERK1/2­NF­κB and Tregs (T­regulatory cells)/IL­11/STAT3 signaling pathways. Of note, several novel mechanisms of Toll­like receptor 4 (TLR4)/NF­κB/STAT3, pSmad3C/3L, nuclear factor erythroid 2­related factor (NrF2)/heme oxygenase 1, circDLST/microRNA­489­3p/eukaryotic translation initiation factor 4A1 and macrophage­related high­mobility group box 1­TLR4 signaling pathways associated with the anticancer activity of AS­IV were also included. Finally, the limitations of current studies that must be addressed in future studies were pointed out to facilitate the establishment of AS­IV as a potent therapeutic drug in cancer treatment.

Flavonoid-Like Components of Peanut Stem and Leaf Extract Promote Sleep by Decreasing Neuronal Excitability.

SCOPE: Peanut stem and leaf (PSL), a traditional Chinese medicine, is widely used as a dietary supplement to improve sleep quality; however, the underlying mechanism is unclear. Here, the study aims to determine whether active compounds in PSL extract exert their effects by mediating neuronal excitability. METHODS AND RESULTS: Aqueous PSL extract (500 mg kg-1 BW) increases the duration of total sleep (TS), slow wave sleep (SWS) and rapid eye movement sleep (REMS) in BALB/c mice after 7 and 14 continuous days of intragastric administration. Two PSL extract components with flavonoid-like structures: 4',7-di-O-methylnaringenin (DMN, 61 µg kg-1 BW) and 2'-O-methylisoliquiritigenin (MIL, 12 µg kg-1 BW), show similar effects on sleep in BALB/c mice. Moreover, incubation with DMN (50 µM) and MIL (50 µM) acutely reduces voltage-gated sodium and potassium currents and suppresses the firing of evoked action potential in mouse cortical neurons, indicating the inhibition on neuronal excitability. Meanwhile, RNA-seq analysis predicts the potential regulation of voltage-gated channels, which is according with the molecular docking simulation that both MIL and DMN can bind to voltage gated sodium channels 1.2 (Nav 1.2). CONCLUSIONS: DMN and MIL are the active ingredients of PSL that improve sleep quality, suggesting that PSL promotes sleep by regulating the excitability of neurons.

Optimal Bands Combination Selection for Extracting Garlic Planting Area with Multi-Temporal Sentinel-2 Imagery.

Garlic is one of the main economic crops in China. Accurate and timely extraction of the garlic planting area is critical for adjusting the agricultural planting structure and implementing rural policy actions. Crop extraction methods based on remote sensing usually use spectral-temporal features. Still, for garlic extraction, most methods simply combine all multi-temporal images. There has been a lack of research on each band's function in each multi-temporal image and optimal bands combination. To systematically explore the potential of the multi-temporal method for garlic extraction, we obtained a series of Sentinel-2 images in the whole garlic growth cycle. The importance of each band in all these images was ranked by the random forest (RF) method. According to the importance score of each band, eight different multi-temporal combination schemes were designed. The RF classifier was employed to extract garlic planting area, and the accuracy of the eight schemes was compared. The results show that (1) the Scheme VI (the top 39 bands in importance score) achieved the best accuracy of 98.65%, which is 6% higher than the optimal mono-temporal (February, wintering period) result, and (2) the red-edge band and the shortwave-infrared band played an essential role in accurate garlic extraction. This study gives inspiration in selecting the remotely sensed data source, the band, and phenology for accurately extracting garlic planting area, which could be transferred to other sites with larger areas and similar agriculture structures.

Epimedium flavonoids protect neurons and synapses in the brain via activating NRG1/ErbB4 and BDNF/Fyn signaling pathways in a chronic cerebral hypoperfusion rat model.

Cerebral hypoperfusion is a common feature of cerebral small vascular disease (CSVD), which has been considered as one of the causes of cognitive decline in recent years. Epimedium flavonoids (EF) are the main ingredients extracted from Epimedium. The purpose of this study was to investigate the effects of EF on cognitive impairment, and the underlying mechanisms in rats with permanent occlusion of the bilateral common carotid artery (2VO). EF (50, 100, and 200 mg/kg) was intragastrically administered for 12 weeks starting 2 weeks after 2VO surgery. The results showed that EF treatment improved learning and memory impairment in 2VO rats evaluated by novel object recognition and Y-maze tests. NeuN immunohistochemical staining indicated that EF alleviated neuronal loss in the hippocampus and cerebral cortex of 2VO rats. MAP-2 immunofluorescence staining and western blotting showed that EF protected neuronal dendrites and increased the expression of cytoskeleton proteins MAP-2 and NF200 in the hippocampus of 2VO rats. Moreover, EF protected the synapse ultrastructure detected by transmission electron microscopy, and increased the expression of synaptic plasticity-related proteins, including synaptophysin, synaptotagmin-I, synapsin I, PSD-95, p-NMDA2B, and p-CaMKII-α in the hippocampus of 2VO rats. In addition, EF increased the expression of neuregulin-1 (NRG-1), p-ErbB4, brain-derived neurotrophic factor (BDNF), p-Fyn, PI3K, p-Akt, and p-CREB in the hippocampus of 2VO rats. These results suggest that EF may protect neurons and synapses by activating the NRG1/ErbB4, BDNF/Fyn, and P13 K/Akt/CREB pathways in the hippocampus and cerebral cortex, thus improving cognitive impairment induced by chronic cerebral hypoperfusion. EF may be a potential candidate drug for chronic cerebral hypoperfusion and CSVD therapy.

Immunostimulatory Potential of MoS2 Nanosheets: Enhancing Dendritic Cell Maturation, Migration and T Cell Elicitation.

BACKGROUND: Due to their extraordinary physical and chemical properties, MoS2 nanosheets (MSNs) are becoming more widely used in nanomedicine. However, their influence on immune systems remains unclear. MATERIALS AND METHODS: Two few-layered MSNs at sizes of 100-250 nm (S-MSNs) and 400-500 nm (L-MSNs) were used in this study. Bone marrow-derived dendritic cells (DCs) were exposed to both MSNs at different doses (0, 8, 16, 32, 64, 128 µg/mL) for 48 h and subjected to analyses of surface marker expression, cytokine secretion, lymphoid homing and in vivo T cell priming. RESULTS: Different-sized MSNs of all doses did not affect the viability of DCs. The expression of CD40, CD80, CD86 and CCR7 was significantly higher on both S-MSN- and L-MSN-treated DCs at a dose of 128 µg/mL. As the dose of MSN increased, the secretion of IL-12p70 remained unchanged, the secretion of IL-1ß decreased, and the production of TNF-α increased. A significant increase in IL-6 was observed in the 128 µg/mL L-MSN-treated DCs. In particular, MSN treatment dramatically improved the ex vivo movement and in vivo homing ability of both the local resident and blood circulating DCs. Furthermore, the cytoskeleton rearrangement regulated by ROS elevation was responsible for the enhanced homing ability of the MSNs. More robust CD4+ and CD8+ T cell proliferation and activation (characterized by high expression of CD107a, CD69 and ICOS) was observed in mice vaccinated with MSN-treated DCs. Importantly, exposure to MSNs did not interrupt LPS-induced DC activation, homing and T cell priming. CONCLUSION: Few-layered MSNs ranging from 100 to 500 nm in size could play an immunostimulatory role in enhancing DC maturation, migration and T cell elicitation, making them a good candidate for vaccine adjuvants. Investigation of this study will not only expand the applications of MSNs and other new transition metal dichalcogenides (TMDCs) but also shed light on the in vivo immune-risk evaluation of MSN-based nanomaterials.

Efficacy and Side Effects of Drugs Commonly Used for the Treatment of Lower Urinary Tract Symptoms Associated With Benign Prostatic Hyperplasia.

Benign prostatic hyperplasia (BPH) is the most common benign disease of the prostate gland and is caused by benign hyperplasia of the smooth muscle cells and stromal cells in this important gland. BPH is also the most common disease underlying lower urinary tract symptoms (LUTS). The incidence of BPH increases with age and affects more than half of all men 50 years or older. BPH mainly exerts effects on urinary function and can seriously reduce a patient's quality of life. At present, treatment for BPH aims primarily to improve the quality of life and reduce the risk of BPH-related complications. Pharmacological therapy is recommended for moderate-to-severe cases of LUTS that are suggestive of BPH. A range of drugs is currently available to treat this condition, including α1-adrenoceptor antagonists, 5α-reductase inhibitors (5-ARIs), phosphodiesterase type 5 inhibitors (PDE5Is), muscarinic receptor antagonists (MRAs), ß3-adrenoceptor agonists, and plant extracts. Of these, the most commonly used drugs in the clinic are α1-adrenoceptor antagonists, 5-ARIs, and combination therapy. However, these drugs exert their effects via various mechanisms and are associated with adverse reactions. The purpose of this review is to provide current comprehensive perspectives on the mechanisms of action, efficacy, and adverse reactions associated with the drugs most commonly used for the treatment of BPH.

Epimedium flavonoids improve cognitive impairment and white matter lesions induced by chronic cerebral hypoperfusion through inhibiting the Lingo-1/Fyn/ROCK pathway and activating the BDNF/NRG1/PI3K pathway in rats.

Chronic cerebral hypoperfusion is a common cause of cerebral small vascular disease (CSVD). White matter (WM) lesions are the typical pathological manifestation of CSVD and contribute to cognitive decline. Epimedium flavonoids (EF) are the main component in Epimedium brevicornu Maxim., which is commonly used in traditional Chinese medicine. The purpose of this study was to investigate the effects of EF on cognitive impairment and the underlying mechanisms in a CSVD rat model induced with chronic cerebral hypoperfusion. The model was established by permanent bilateral common carotid artery occlusion (2VO) in rats. EF (50, 100, and 200 mg/kg) was intragastrically administered once a day for 12 weeks starting 2 weeks after 2VO surgery. The learning and memory capacity of the rats were measured using the Morris water maze and step-through tests. WM lesions were observed by MRI-diffusion tensor imaging, transmission electron microscopy, and LFB staining. Oligodendrocytes were detected by immunohistochemistry. Western blotting assay was used to determine the level of protein expression. The results showed that EF significantly improved learning and memory impairment, alleviated WM nerve fiber injuries and demyelination, and increased the number of mature oligodendrocytes in the corpus callosum, subcortical WM, and periventricular WM in 2VO rats. Mechanistically, EF reduced the expression of Lingo-1 and ROCK2 and increased the levels of phosphorylated (p-) Fyn, brain-derived neurotrophic factor (BDNF), TrkB, neuregulin-1 (NRG-1), p-ErbB4, PI3K p85 and p110α, p-Akt, and p-CREB in the corpus callosum of 2VO rats. These results suggest that EF may improve cognitive impairment and WM lesions induced by chronic cerebral hypoperfusion through inhibiting the Lingo-1/Fyn/ROCK pathway and activating the BDNF/TrkB, NRG-1/ErbB4, and the downstream PI3K/Akt/CREB pathways in WM. Thus, EF can be used as a potential neuroprotective agent in CSVD therapy.

Sanhua Decoction, a Classic Herbal Prescription, Exerts Neuroprotection Through Regulating Phosphorylated Tau Level and Promoting Adult Endogenous Neurogenesis After Cerebral Ischemia/Reperfusion Injury.

Background: Ischemia stroke is the leading cause of death and long-term disability. Sanhua Decoction (SHD), a classic Chinese herbal prescription, has been used for ischemic stroke for about thousands of years. Here, we aim to investigate the neuroprotective effects of SHD on cerebral ischemia/reperfusion (CIR) injury rat models. Methods: The male Sprague-Dawley rats (body weight, 250-280 g; age, 7-8 weeks) were randomly divided into sham group, CIR group, and SHD group and were further divided into subgroups according to different time points at 6 h, 1, 3, 7, 14, 21, and 28 d, respectively. The SHD group received intragastric administration of SHD at 10 g kg-1 d-1. The focal CIR models were induced by middle cerebral artery occlusion according to Longa's method, while sham group had the same operation without suture insertion. Neurological deficit score (NDS) was evaluated using the Longa's scale. BrdU, doublecortin (DCX), and glial fibrillary acidic protein (GFAP) were used to label proliferation, migration, and differentiation of nerve cells before being observed by immunofluorescence. The expression of reelin, total tau (t-tau), and phosphorylated tau (p-tau) were evaluated by western blot and RT-qPCR. Results: SHD can significantly improve NDS at 1, 3, 7, and 14 d (p < 0.05), increase the number of BrdU positive and BrdU/DCX positive cells in subventricular zone at 3, 7, and 14 d (p < 0.05), upregulate BrdU/GFAP positive cells in the ischemic penumbra at 28 d after CIR (p < 0.05), and reduce p-tau level at 1, 3, 7, and 14 d (p < 0.05). There was no significant difference on reelin and t-tau level between three groups at each time points after CIR. Conclusions: SHD exerts neuroprotection probably by regulating p-tau level and promoting the proliferation, migration, and differentiation of endogenous neural stem cells, accompanying with neurobehavioral recovery.

Cornel Iridoid Glycoside Suppresses Hyperactivity Phenotype in rTg4510 Mice through Reducing Tau Pathology and Improving Synaptic Dysfunction.

rTg4510 mice are transgenic mice expressing P301L mutant tau and have been developed as an animal model of tauopathies including Alzheimer's disease (AD). Besides cognitive impairments, rTg4510 mice also show abnormal hyperactivity behavior. Cornel iridoid glycoside (CIG) is an active ingredient extracted from Cornus officinalis, a traditional Chinese herb. The purpose of the present study was to investigate the effects of CIG on the emotional disorders such as hyperactivity, and related mechanisms. The emotional hyperactivity was detected by locomotor activity test and Y maze test. Immunofluorescent and immunohistochemical analyses were conducted to measure neuron loss and phosphorylated tau. Western blotting was used to detect the expression of related proteins. The results showed that intragastric administration of CIG for 3 months decreased the hyperactivity phenotype, prevented neuronal loss, reduced tau hyperphosphorylation and aggregation in the amygdala of rTg4510 mice. Meanwhile, CIG alleviated the synaptic dysfunction by increasing the expression of N-methyl-D-aspartate receptors (NMDARs) subunits GluN1 and GluN2A and αamino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) subunits GluA1 and GluA2, and increased the level of phosphorylated Ca2+/calmodulin dependent protein kinase II α (p-CaMK IIα) in the brain of rTg4510 mice. In conclusion, CIG may have potential to treat the emotional disorders in tauopathies such as AD through reducing tau pathology and improving synaptic dysfunction.

Update on treatment and preventive interventions against COVID-19: an overview of potential pharmacological agents and vaccines.

The outbreak of coronavirus disease 2019 (COVID-19) triggered by the new member of the coronaviridae family, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has created an unprecedented challenge for global health. In addition to mild to moderate clinical manifestations such as fever, cough, and fatigue, severe cases often developed lethal complications including acute respiratory distress syndrome (ARDS) and acute lung injury. Given the alarming rate of infection and increasing trend of mortality, the development of underlying therapeutic and preventive treatment, as well as the verification of its effectiveness, are the top priorities. Current research mainly referred to and evaluated the application of the empirical treatment based on two precedents, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), including antiviral drugs targeting different stages of virus replication, immunotherapy modulating the overactivated inflammation response, and other therapies such as herbal medicine and mesenchymal stem cells. Besides, the ongoing development of inventing prophylactic interventions such as various vaccines by companies and institutions worldwide is crucial to decline morbidity and mortality. This review mainly focused on promising candidates for the treatment of COVID-19 and collected recently updated evidence relevant to its feasibility in clinical practice in the near future.

Dynamics of soil microbial C:N:P stoichiometry and its driving mechanisms following natural vegetation restoration after farmland abandonment.

Vegetation restoration after farmland abandonment has increased greatly and is commonly used to improve soil fertility and ecosystem service. Knowledge of soil community-level elemental homeostasis following natural vegetation restoration is specially limited for the abandoned farmlands. This study examined the changes in soil microbial biomass stoichiometry and homeostasis with a chronosequence of 3, 8, 13, 18, 23 and 30 years following natural vegetation restoration since farmland abandonment on the Loess Plateau, China. Vegetation communities, soil properties, microbial communities, and enzyme activities were analyzed to study the drivers on soil microbial C:N:P stoichiometry. The results showed that soil microbial biomass C: N ratios had little change following natural vegetation restoration since farmland abandonment, natural vegetation >23 years had significantly enhanced the microbial biomass C:P and N:P ratios by 26.1%-133.9% and 31.7%-67.4%, respectively. However, microbial biomass C:N, C:P and N:P ratios were constrained following natural vegetation restoration. Vegetation restoration for 30 years enhanced urease and alkaline phosphatase activities by 125.4% and 42.9%, respectively, which showed synchronous changes with N and P contents in microbial biomass. Soil fungi, urease and alkaline phosphatase were the drivers to the changes in microbial C:N:P stoichiometry. The results suggest that long-term vegetation restoration (>23 years) will aggravate microbial P limitation, however, soil microorganism maintained the homeostatic regulation of stoichiometric ratios to mitigate P limitation. Fungi played a strong role in shaping microbial community-level elemental homeostasis and nutrient cycling through releasing N-converting and P-converting enzymes into soil following natural vegetation restoration.

Patterns of soil microbial nutrient limitations and their roles in the variation of soil organic carbon across a precipitation gradient in an arid and semi-arid region.

The effects of precipitation patterns on the metabolism of soil microbes are poorly understood, especially in water-limited ecosystems where soil microorganisms play crucial roles in the turnover of soil organic carbon (SOC) and nutrients. We investigated the influence of the gradient levels of mean annual precipitation (MAP from 300 to 900 mm) on soil microbial metabolism in an arid and semi-arid grassland region located in Loess Plateau, China and identified relationships between microbial metabolic limitations and the variation of soil organic matter (SOM). Microbial metabolism in this arid and semi-arid region was limited by soil C and phosphorus (P) or nitrogen (N). Microbial C and P limitations decreased with the increase of MAP. Microbial C and P limitations were lowest in the areas with MAPs of 700-900 mm, whereas N limitation was observed in the areas with MAPs >700 mm. The results of a variation-partitioning analysis and partial least squares path modeling indicated that the microbial C and N/P limitations on regional scales were mainly determined by climate factors (MAP and mean annual temperature (MAT)), followed by vegetation biomass and soil properties. The extents of soil drying-rewetting processing caused by different MAPs directly affected microbial nutrient limitation. Our results suggested that the influence of precipitation variation on microbial metabolic limitation strongly governed SOM stability and that an increase in the rate of SOM decomposition with increasing precipitation could be caused by increased microbial nutrient limitation. SOM may be most stable at a MAP of 700 mm in the arid and semi-arid regions (300-900 mm MAP) where microbial nutrient limitation was lowest. This study provided novel insights into the responses of soil microbial metabolism to precipitation change and is an important step toward understanding the mechanisms of SOM stability in an arid and semi-arid grassland ecosystem under scenarios of precipitation variation.

Sedative-hypnotic and anxiolytic effects and the mechanism of action of aqueous extracts of peanut stems and leaves in mice.

INTRODUCTION: Peanut stems and leaves (PSL) have traditionally been used as both a special food and a herbal medicine in Asia. The sedative-hypnotic and anxiolytic effects of PSL have been recorded in classical traditional Chinese literature, and more recently by many other researchers. In a previous study, four sleep-related ingredients (linalool, 5-hydroxy-4',7-dimethoxyflavanone, 2'-O-methylisoliquiritigenin and ferulic acid), among which 5-hydroxy-4',7-dimethoxyflavanone and 2'-O-methylisoliquiritigenin were newly found in Arachis species, were screened by ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC/QTOF-MS). In the current study, quantitative examination of the above four ingredients was conducted. Serious fundamental functional studies were done in mice, including locomotor activity, direct sleep tests, pentobarbital-induced sleeping time tests, subthreshold dose of pentobarbital tests and barbital sodium sleep incubation period tests, to determine the material base for the sedative-hypnotic and anxiolytic effects of aqueous extracts of PSL. Furthermore, neurotransmitter levels in three brain regions (cerebrum, cerebellum and brain stem) were determined using UHPLC coupled with triple-quadrupole mass spectrometry (UHPLC/QQQ-MS) in order to elucidate the exact mechanism of action. RESULTS: Aqueous extract of PSL at a dose of 500 mg kg-1 (based on previous experience), along with different concentrations of the above four functional ingredients (189.86 µg kg-1 linalool, 114.75 mg kg-1 5-hydroxy-4',7-dimethoxyflavanone, 32.4mg kg-1 2'-O-methylisoliquiritigenin and 44.44 mg kg-1 ferulic acid), had a sedative-hypnotic effect by affecting neurotransmitter levels in mice. CONCLUSION: The data demonstrate that these four ingredients are the key functional factors for the sedative-hypnotic and anxiolytic effects of PSL aqueous extracts and that these effects occur via changes in neurotransmitter levels and pathways. © 2018 Society of Chemical Industry.

Cornel Iridoid Glycoside Improves Locomotor Impairment and Decreases Spinal Cord Damage in Rats.

Purpose. This study was to investigate the effects of cornel iridoid glycoside (CIG) on spinal cord injury (SCI) in rats. Methods. The thoracic cord (at T9) of rats was injured by clip compression for 30 sec. Locomotor function was assessed using the Basso, Beattie, and Bresnahan (BBB) rating scale. Neuroanatomic stereological parameters as well as Nogo-A, p75 neurotrophin receptor (p75NTR), and ROCKII expression were measured by histological processing, immunohistochemistry, and stereological analyses. The axons passing through the lesion site were detected by BDA tracing. Results. Intragastric administration of CIG (60 and 180 mg/kg) improved the locomotor impairment at 10, 17, 24, and 31 days post-injury (dpi) compared with untreated SCI model rats. CIG treatment decreased the volume of the lesion epicenter (LEp) and increased the volume of spared tissue and the number of surviving neurons in the injured spinal cord at 31 dpi. CIG promoted the growth of BDA-positive axons and their passage through the lesion site and decreased the expression of Nogo-A, p75NTR, and ROCKII both in and around the LEp. Conclusion. CIG improved the locomotor impairment, decreased tissue damage, and downregulated the myelin-associated inhibition signaling pathway in SCI rats. The results suggest that CIG may be beneficial for SCI therapy.

Identification of chemical ingredients of peanut stems and leaves extracts using UPLC-QTOF-MS coupled with novel informatics UNIFI platform.

Peanut stems and leaves have been used traditionally as both herbal medicines and special food in Asia. In this study, the main functional compounds of peanut stems and leaves extracts were identified using UPLC separation coupled to high resolution mass spectrometry (QTOF-MS), and a traditional medicine library. Three different extraction solvents (ethyl acetate, petroleum ether and n-butanol) were evaluated to prepare the extracts of peanut stems and leaves. A total of 283 chemical compounds were identified in peanut stems and leaves extracts, of which 207 compounds are tentatively new identifications in Genus Arachis. The integration of data acquisition and processing with the traditional medicine library provides a simple, efficient process to effectively facilitate the identification of chemical ingredients in complex natural product extracts. The integrated workflow for separation, detection and identification of functional compounds in natural products using UPLC/QTOF-MS greatly improves productivity for development of traditional herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd.

Effect of desertification on productivity in a desert steppe.

Desertification, one of the most severe types of land degradation in the world, is of great importance because it is occurring, to some degree, on approximately 40% of the global land area and is affecting more than 1 billion people. In this study, we used a space-for-time method to quantify the impact of five different desertification regimes (potential (PD), light (LD), moderate (MD), severe (SD), and very severe (VSD)) on a desert steppe ecosystem in northern China to examine the relationship between the productivity of the vegetation and soil properties and to determine the mechanism underlying the effects of desertification on productivity. Our results showed that the effects of desertification on TP (total phosphorus) and AP (available phosphorus) were not significant, and desertification decreased productivity in the desert steppe as a result of direct changes to soil physical properties, which can directly affect soil chemical properties. Therefore, intensive grassland management to improve soil quality may result in the long-term preservation of ecosystem functions and services.

Electroacupuncture for Acute Ischemic Stroke: A Meta-Analysis of Randomized Controlled Trials.

Electroacupuncture (EA) is an extension technique of acupuncture based on traditional acupuncture combined with modern electrotherapy. Here, we conducted a systematic review specifically to assess the effectiveness and safety of EA for acute ischemic stroke. Eight databases were searched for randomized-controlled clinical trials (RCTs) of EA for acute ischemic stroke published from inception to June 2013. Ultimately, 67 studies claimed to be RCTs. Eighteen studies with 1411 individuals were selected for the analyses, which got ≥ 4 "yes" in the domains of Cochrane risk of bias tool. The meta-analysis showed a significant effect of EA for improving Barthel Index (p < 0.00001), Fugl-Meyer Assessment (p < 0.00001), National Institutes of Health Stroke Scale (p < 0.00001), and Revised Scandinavian Stroke Scale (p < 0.00001) compared with western conventional treatments (WCTs). In an analysis of the total clinical efficacy rate, there was a significant difference between EA and WCTs (p=0.0002). Adverse effects were monitored in 6 studies, and were well tolerated in all stroke patients. According to the GRADE approach, the quality of evidence was mostly high or moderate. In conclusion, this systematic review revealed the evidence in support of the use of EA for acute ischemic stroke, although further larger sample-size and rigorously designed RCTs are required.