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.