Targeting Mitochondrial Dysfunction With LncRNAs in a Wistar Rat Model of Chronic Obstructive Pulmonary Disease.

BACKGROUND/AIM: Chronic obstructive pulmonary disease (COPD) has become a prominent healthcare issue in recent years. Cigarette smoking (CS) and fine particulate matter (PM2.5) are important causative factors for COPD. This study assessed the aberrant lncRNA profiles in the tissue of rats with COPD caused by CS or PM2.5 Materials and Methods: A COPD rat model was developed using CS (CSM) or PM2.5 (PMM), and lung tissue RNA was extracted. The Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) were used to investigate the correlations between the distinct lncRNAs and mRNA pathways. A coding-non-coding gene co-expression network (CNC) was constructed by establishing connections between differentially expressed long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) associated with mitochondrial dysfunction and the inflammatory response. RESULTS: A quantitative real-time reverse transcription PCR (qRT-PCR) experiment was performed to verify the expression of the particular lncRNAs. Microarray analysis of lung tissue from the COPD model revealed that 123 and 444 lncRNAs were substantially raised and reduced in PMM vs. the control group (Ctrl), respectively, as were 621 and 1,178 mRNAs. Meanwhile, 81 and 340 lncRNAs were consistently raised and lowered in CSM vs. Ctrl, respectively, as were 408 and 931 mRNAs. GO enrichment and KEGG pathway analysis indicated that the COPD model was connected to inflammatory responses, mitochondrial dysfunction, and others. CONCLUSION: XR_340674, ENSRNOT00000089642, XR_597045, and XR_340651 were decreased, and XR_592469 was elevated. These lncRNAs were shown to be related to mitochondrial dysfunction in the lung tissue of animals exposed to CS or PM2.5.

Involvement of NEAT1/PINK1-mediated mitophagy in chronic obstructive pulmonary disease induced by cigarette smoke or PM2.5.

Background: This study sought to explore the underlying mechanism of long non-coding ribonucleic acid nuclear enriched abundant transcript 1 (NEAT1) and PTEN-induced kinase 1 (PINK1)-mediated mitophagy in chronic obstructive pulmonary disease (COPD) induced by cigarette smoke (CS) or fine particular matter (PM2.5). Methods: In total, 30 male Wistar Rats were divided into the following 3 groups: (I) the COPD group exposed to CS (CSM); (II) the COPD group exposed to PM2.5 (PMM); and (III) the control (Ctrl) group. Pulmonary function, the enzyme-linked immunoassay analysis results, the histopathology results, and the ultrastructures of the lung tissues were examined in the 3 groups, and NEAT1 expression levels and the mitophagy-related protein PINK1, Parkin, LC3B, and p62 levels were assessed by quantitative reverse transcription PCR (RT-qPCR) and Western blotting. The A549 cells were transfected with small interfering ribonucleic acid (siRNA) targeting NEAT1, and subsequently stimulated with CS extract (CSE) and PM2.5 suspension (PMS). Mitochondrial dysfunction and enhanced mitophagy were observed, and the expression of the NEAT1/PINK1 pathway was assessed by RT-qPCR and Western blotting. Results: Both the CSM and PMM groups had a lower tidal volume (VT), minute ventilation (MV), and a higher respiratory rate (f) than the Ctrl group. The interleukin (IL)-6, IL-8, and tumor necrosis factor-alpha levels in the serum and bronchoalveolar lavage fluid of the CSM and PMM groups were significantly increased. The histological examination results revealed airway remodeling, the formation of pulmonary bullae, and emphysema in the CSM and PMM groups. Subsequently, the ultrastructures of the lung tissues in the CSM and PMM groups showed mitochondrial swelling and autophagosomes. Additionally, NEAT1 expression, the level of the mitophagy-related protein PINK1, Parkin, and the ratio of LC3-II/I increased synchronously. Further, NEAT1 siRNA blocked PINK1 expression, inhibited mitochondrial dysfunctions, and mitophagy activation in the A549 cells exposed to CSE or PMS. Conclusions: Our results suggest that CS and PM2.5 exposure induce mitochondrial dysfunction, and the NEAT1/PINK1 pathway plays a critical role in the occurrence and development of COPD by regulating mitophagy.

Dendrocrepidamine, a novel octahydroindolizine alkaloid from the roots of Dendrobium crepidatum.

A novel octahydroindolizine alkaloid, named dendrocrepidamine (1) with an unusual 18,19,19'-cyclopropanone-dendrocrepine skeleton, was isolated from the ethanol extract of the roots of Dendrobium crepidatum, along with six known compounds (2-7). The structure of 1 was elucidated through HR-ESIMS, NMR spectroscopic data and computational calculations. All compounds were examined for their inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 cells with IC50 values in the range of 3.04-54.89 µM. In vivo, crepidatin (6) (80, 40 and 10 mg/kg) showed a significant protective effect against LPS-induced acute lung injury (ALI) in mice.

Rapid generation of inoculum of a plant RNA virus using overlap PCR.

We have developed an efficient method to rapidly generate infectious inoculum of a plant RNA virus and confirmed its infectivity by mechanical inoculation. The method takes advantage of overlap PCR to bypass the cloning steps, which makes it relatively simple, rapid, and inexpensive compared to the traditional methods. Using this approach, inoculum of a tobamovirus, Turnip vein clearing virus (TVCV), was generated. PCR products specific for the 35S promoter and TVCV genome were used as templates for overlap PCR to form a single product containing the full-length TVCV cDNA under the control of the double 35S promoter, and the entire process took only 8 h. This inoculum was infectious in Nicotiana benthamiana, and its infectivity was ca. 67% compared to 0% and 100% with negative and positive controls, respectively. Thus, this rapid method generates efficient infectious inoculum for a plant RNA virus.

Enantioselective Cascade Biocatalysis for Deracemization of Racemic ß-Amino Alcohols to Enantiopure (S)-ß-Amino Alcohols by Employing Cyclohexylamine Oxidase and ω-Transaminase.

Optically active ß-amino alcohols are very useful chiral intermediates frequently used in the preparation of pharmaceutically active substances. Here, a novel cyclohexylamine oxidase (ArCHAO) was identified from the genome sequence of Arthrobacter sp. TYUT010-15 with the R-stereoselective deamination activity of ß-amino alcohol. ArCHAO was cloned and successfully expressed in E. coli BL21, purified and characterized. Substrate-specific analysis revealed that ArCHAO has high activity (4.15 to 6.34 U mg-1 protein) and excellent enantioselectivity toward the tested ß-amino alcohols. By using purified ArCHAO, a wide range of racemic ß-amino alcohols were resolved, (S)-ß-amino alcohols were obtained in >99 % ee. Deracemization of racemic ß-amino alcohols was conducted by ArCHAO-catalyzed enantioselective deamination and transaminase-catalyzed enantioselective amination to afford (S)-ß-amino alcohols in excellent conversion (78-94 %) and enantiomeric excess (>99 %). Preparative-scale deracemization was carried out with 50 mM (6.859 g L-1 ) racemic 2-amino-2-phenylethanol, (S)-2-amino-2-phenylethanol was obtained in 75 % isolated yield and >99 % ee.

Limonoids and tricyclic diterpenoids from Azadirachta indica and their antitumor activities.

The chemical constituents of the roots, seeds, and bark of Azadirachta indica var. siamensis were investigated, leading to the isolation of six tricyclic diterpenoids and five limonoids, including two new compounds (2, 5). The structures were elucidated based on NMR spectroscopic techniques, mass spectrometry and single-crystal X-ray diffraction as well as comparison with the literature. Moreover, the cytotoxicity activities of the isolates were evaluated. The results indicated that the compounds 1-3, 5-9 exhibited cytotoxicities against one or more cancer cell lines tested, with IC50 values in the range of 1.7-88.1 µM. The mechanism of action studies indicated that the most active compound, compound 5, could induce the apoptosis of AZ521 cells. Furthermore, the Western blot analysis showed that compound 5 could reduce the expression levels of procaspases-3, -8, -9 and promote the expression of Bid and AIF.

Sauropus androgynus L. Merr.-A phytochemical, pharmacological and toxicological review.

ETHNOPHARMACOLOGICAL RELEVANCE: Sauropus androgynus L. Merr is an underexploited perennial shrub traditionally used as a medicinal plant in South Asia and Southeast Asia. The plant is regarded as not just a green vegetable for diet, but as a traditional herb for certain aliments. For instance, it has traditionally been used to relieve fever, to treat ulcers and diabetes, to promote lactation and eyesight, and to reduce obesity. AIM OF THE STUDY: This paper aims to review the botany, phytochemistry, ethnopharmacology, and pharmacological activities of S. androgynus, and discuss the known chemical constituents at work in S. androgynus-induced bronchiolitis obliterans for providing new ideas to the mechanism of the disease and pharmacology research of the plant. MATERIALS AND METHODS: The data presented in this review were collected from published literatures as well as the electronic databases of PubMed, CNKI, Web of Science, SCI finder, ACS, Science Direct, Wiley, Springer, Taylor, Google Scholar, and a number of unpublished resources, (e.g. books, and Ph.D. and M.Sc. dissertations). RESULTS: The scientific literature indicates that S. androgynus is a valuable and popular herbal medicine whose nutritional value is also higher than that of other commonly used vegetables. Phytochemical analyses identified high content of fatty acids, flavonoids, and polyphenols as the major bioactive components in S. androgynus. Crude extracts and phytochemical compounds isolated from S. androgynus show a wide spectrum of in vitro and in vivo pharmacological activities such as antioxidant, anti-inflammatory, anti-ulcer, skin whitening, anti-diabetic, and immunoregulatory activities. The traditional use, such as increasing lactation, treating ulcers and diabetes, and reducing obesity, have been evaluated and studied with various methods. Numerous reports have revealed the unusual link between the consumption of S. androgynus and the induction of a chronic and irreversible obstructive disease (namely, bronchiolitis obliterans), indicating that the toxicity and side effects of this plant that is presently used in health care and medicine are a major area of concern. CONCLUSION: Though little importance was attached to this green plant, S. androgynus has notable phytochemical constituents and various pharmacological activities including antioxidant, anti-inflammatory, and anti-obesity activities. Studies have firmly established the association between excessive consumption of the uncooked S. androgynus juice over a period of time and the occurrence of bronchiolitis obliterans. It is inadvisable to ingest excessive amounts of S. androgynus before fully understanding the pathogenesis and induction mechanism of this fatal disease. The phytochemistry of S. androgynus, its pharmacology for traditional use, S. androgynus-induced bronchiolitis obliterans still need further investigation.

Traditional uses, phytochemistry, and pharmacology of Ficus hispida L.f.: A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Ficus hispida L.f. (Moraceae) has long been used as a traditional medicine in India, China, Sri Lanka, Australia, and Myanmar in the treatment of diarrhea, ulcer, anemia, diabetes, inflammation, and cancer. AIM OF THE REVIEW: This review provides a systematic comment on the botany, traditional uses, and phytochemical and pharmacological studies of F. hispida, with an aim to make critical update of the current knowledge and obtain opportunities for further therapeutic potential. MATERIALS AND METHODS: The information was derived from scientific literature databases including PubMed, Baidu Scholar, Google Scholar, Web of Science, and Science Direct. Additional information was gathered from books, Ph.D. and M.Sc. dissertations, and unpublished materials. RESULTS AND DISCUSSION: F. hispida is used especially in Chinese and Indian traditional medical systems as a remedy for skin disorders, respiratory diseases, and urinary diseases. Wound healing, anti-inflammatory, antinociceptive, sedative, antidiarrheal, antiulcer, antimicrobial, antioxidant, hepatoprotective, antineoplastic, and antidiabetic activities have been reported for crude extracts and isolated metabolites, but the methodologies in these studies often have inadequate design and low technical quality. More than 76 compounds have been isolated from F.hispida, including sesquiterpenoids and triterpenoids, flavonoids, coumarins, phenylpropionic acids, benzoic acid derivatives, alkaloids, steroids, other glycosides, and alkanes, but the method of bioassay-guided fractionation is seldom applied in the isolation from F. hispida. CONCLUSION: F. hispida is used widely in traditional medicines and has multiple pharmacological effects that could support traditional uses. However, pharmacological studies should be viewed with caution because of the inappropriate experimental design. More in vitro and in vivo research is urgently needed to study the molecular mechanisms and assess the effective and safe dose of F. hispida.

Alpha-Mangostin Ameliorates Bleomycin-Induced Pulmonary Fibrosis in Mice Partly Through Activating Adenosine 5'-Monophosphate-Activated Protein Kinase.

Background: Pulmonary fibrosis (PF) is a devastating interstitial lung disease and characterized by an abnormal accumulation of extracellular matrix (ECM). Nintedanib (NDN) and pirfenidone are two approved therapies for PF, but their potential side-effects have been reported. Recently, the use of natural supplements for PF is attracting attention. Alpha-mangostin (α-MG) is an active xanthone-type compound isolated from the nutritious fruit mangosteen. Purpose: In the present study, the potential effect and underlying mechanism of α-MG were evaluated in bleomycin (BLM)-induced PF and activated primary lung fibroblasts (PLFs). Methods: Histopathological changes and collagen deposition were analyzed via hematoxylin-eosin staining and Masson staining, the expression of nicotinamide adenine dinucleotide phosphate oxidase-4 (NOX4) involved in oxidative stress in lung tissues was analyzed by immunochemistry staining. The expressions of α-smooth muscle actin (α-SMA), collagen I (Col I), p-adenosine 5'-monophosphate-activated protein kinase (AMPK)/AMPK, and NOX4 were detected by Western blot, immunofluorescence or RT-PCR, and effects of α-MG on cell viability were detected using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide. Results: In vivo results demonstrated that α-MG treatment (10 mg/kg/day) significantly ameliorated BLM-induced deposition of ECM in lung tissues. Moreover, α-MG could inhibit protein expressions of α-SMA and Col I as well as its mRNA levels. In addition, α-MG also significantly inhibited transforming growth factor-ß1/Smad2/3 pathway and regulated the protein expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in lung tissues. In vitro results demonstrated that α-MG significantly increased p-AMPK/AMPK but reduced the protein expression level of α-SMA and Col I as well as NOX4 in activated PLFs. Further study demonstrated that these improvement effects were significantly blocked by compound C. Conclusion: α-MG treatment significantly decreased oxidative stress in lungs partly by activating AMPK mediated signaling pathway in BLM-induced PF and activated PLFs and decreased the deposition of ECM. The present study provides pharmacological evidence to support therapeutic application of α-MG in the treatment of PF.

Vitellaria paradoxa nutshells from seven sub-Saharan countries as potential herbal medicines for treating diabetes based on chemical compositions, HPLC fingerprints and bioactivity evaluation.

The aim of the study was to determine the feasibility of the Vitellaria paradoxa nutshell as a new medicinal resource for treating diabetes. A total of forty-one compounds were identified by HPLC-DAD-Q-TOF-MS and phytochemical methods in V. paradoxa nutshell methanol extract. Based on HPLC fingerprints, four characteristic constituents were quantified and the origin of twenty-eight V. paradoxa nutshells from seven sub-Saharan countries was compared, which were classified into three groups with chemometric method. Twenty-eight samples contained high total phenolic content, and exhibited moderate-higher antioxidant activity and strong α-glucosidase inhibitory activity. Furthermore, all fractions and isolated compounds were evaluated for their antioxidant and α-glucosidase inhibitory activities, and α-glucosidase inhibitory action mechanism of four characteristic constituents including protocatechuic acid, 3, 5, 7-trihydroxycoumarin, (2R, 3R)-(+)-taxifolin and quercetin was investigated via molecular docking method, which were all stabilized by hydrogen bonds with α-glucosidase. The study provided an effective approach to waste utilization of V. paradoxa nutshell, which would help to resolve waste environmental pollution and provide a basis for developing potential herbal resource for treating diabetes.

A C21-Steroidal Glycoside from Cynanchum atratum Attenuates Concanavalin A-Induced Liver Injury in Mice.

Cynatratoside A (CyA) is a C21 Steroidal glycoside with pregnane skeleton isolated from the root of Cynanchum atratum Bunge (Asclepiadaceae). This study aimed to investigate the effects of CyA on concanavalin A (Con A)-induced autoimmune hepatitis (AIH) and the underlying mechanism. CyA was orally administered to mice at 10 and 40 mg/kg 8 h before and 1 h after Con A treatment. The effects of CyA on Con A-induced spleen and liver in mice were assessed via histopathological changes, T lymphocyte amounts and the expressions of IL-1ß and ICAM-1. Con A-induced L-02 hepatocytes were used to evaluate whether CyA (0.1⁻10 µM) can directly protect hepatocytes from cytotoxicity and the possible mechanism. The results revealed that CyA treatment could significantly improve the histopathological changes of spleen and liver, reduce the proliferation of splenic T lymphocytes, and decrease the expressions of IL-1ß and ICAM-1 in liver. The experiment in vitro showed that CyA inhibited Con A-induced hepatotoxicity in a concentration-dependent manner. CyA (10 µM) significantly increased/decreased the expression of Bcl-2/Bax and reduced the levels of cleaved caspases-9 and -3. Our study demonstrated for the first time that CyA has a significant protective effect on Con A-induced AIH by inhibiting the activation and adhesion of T lymphocytes and blocking hepatocyte apoptosis.

Wedelolactone Attenuates Pulmonary Fibrosis Partly Through Activating AMPK and Regulating Raf-MAPKs Signaling Pathway.

Pulmonary fibrosis is common in a variety of inflammatory lung diseases, there is currently no effective clinical drug treatment. It has been reported that the ethanol extract of Eclipta prostrata L. can improve the lung collagen deposition and fibrosis pathology induced by bleomycin (BLM) in mice. In the present study, we studied whether wedelolactone (WEL), a major coumarin ingredient of E. prostrata, provided protection against BLM-induced pulmonary fibrosis. ICR or C57/BL6 strain mice were treated with BLM to establish lung fibrosis model. WEL (2 or 10 mg/kg) was given daily via intragastric administration for 2 weeks starting at 7-day after intratracheal instillation. WEL at 10 mg/kg significantly reduced BLM-induced inflammatory cells infiltration, pro-inflammatory factors expression, and collagen deposition in lung tissues. Additionally, treatment with WEL also impaired BLM-induced increases in fibrotic marker expression (collagen I and α-SMA) and decrease in an anti-fibrotic marker (E-cadherin). Treatment with WEL significantly prevented BLM-induced increase in TGF-ß1 and Smad2/3 phosphorylation in the lungs. WEL administration (10 mg/kg) also significantly promoted AMPK activation compared to model group in BLM-treated mice. Further investigation indicated that activation of AMPK by WEL can suppressed the transdifferentiation of primary lung fibroblasts and the epithelial mesenchymal transition (EMT) of alveolar epithelial cells, the inhibitive effects of WEL was significantly blocked by an AMPK inhibitor (compound C) in vitro. Together, these results suggest that activation of AMPK by WEL followed by reduction in TGFß1/Raf-MAPK signaling pathways may have a therapeutic potential in pulmonary fibrosis.

Neotuberostemonine inhibits the differentiation of lung fibroblasts into myofibroblasts in mice by regulating HIF-1α signaling.

Pulmonary fibrosis may be partially the result of deregulated tissue repair in response to chronic hypoxia. In this study we explored the effects of hypoxia on lung fibroblasts and the effects of neotuberostemonine (NTS), a natural alkaloid isolated from Stemona tuberosa, on activation of fibroblasts in vitro and in vivo. PLFs (primary mouse lung fibroblasts) were activated and differentiated after exposure to 1% O2 or treatment with CoCl2 (100 µmol/L), evidenced by markedly increased protein or mRNA expression of HIF-1α, TGF-ß, FGF2, α-SMA and Col-1α/3α, which was blocked after silencing HIF-1α, suggesting that the activation of fibroblasts was HIF-1α-dependent. NTS (0.1-10 µmol/L) dose-dependently suppressed hypoxia-induced activation and differentiation of PLFs, whereas the inhibitory effect of NTS was abolished by co-treatment with MG132, a proteasome inhibitor. Since prolyl hydroxylation is a critical step in initiation of HIF-1α degradation, we further showed that NTS treatment reversed hypoxia- or CoCl2-induced reduction in expression of prolyl hydroxylated-HIF-1α. With hypoxyprobe immunofiuorescence staining, we showed that NTS treatment directly reversed the lower oxygen tension in hypoxia-exposed PLFs. In a mouse model of lung fibrosis, oral administration of NTS (30 mg·kg-1·d-1, for 1 or 2 weeks) effectively attenuated bleomycin-induced pulmonary fibrosis by inhibiting the levels of HIF-1α and its downstream profibrotic factors (TGF-ß, FGF2 and α-SMA). Taken together, these results demonstrate that NTS inhibits the protein expression of HIF-1α and its downstream factors TGF-ß, FGF2 and α-SMA both in hypoxia-exposed fibroblasts and in lung tissues of BLM-treated mice. NTS with anti-HIF-1α activity may be a promising pharmacological agent for the treatment of pulmonary fibrosis.

[Capsaicin Alleviate Myocardial Ischemia Reperfusion Injury Through Attenuating Mitochondrial Oxidative Stress].

OBJECTIVE: To investigate the role of capsaicin (CAP) in myocardial ischemia reperfusion injury and its underlying mechanisms. METHODS: Twentyfour adult male SD rats were randomized into 4 groups,namely the control group,ischemia reperfusion group,ischemia reperfusion with CAP group,and ischemia reperfusion with CAPZ and CAP group. Isolated rat hearts underwent Langendorff perfusion. Left ventricular enddiastolic pressure (LVEDP) andleft ventricular developed pressure (LVDP) was calculated to evaluate myocardial performance at 30 min of reperfusion.Triphenyltetrazolium chloride staining was used to measure the infarct size of myocardium at 120 min reperfusion. The morphological changes in myocardial fiber was analyzed by HE staining at the end of reperfusion. Lactate dehydrogenase (LDH) content in the coronary flow was determined during the first 5 min reperfusion. The myocardial mitochondria was isolated and extracted for measuring a series of indicators of mitochondrial oxidative stress,including superoxide dismutase (SOD),methane dicarboxylic aldehyde (MDA) at the end of reperfusion. Western blot was used to determine the expression of caspase3 and cytochrome c at 10 min reperfusion. RESULTS: Compared with the control group,IR group significantly decreased in cardiac function,the level of LVDP and SOD activity and induced an enlarged infarct size ( P<0.01),accompanied by the disordered arrangement of myocardial cells,the content of MDA was increased ( P<0.01),the content of caspase3 and cytochrome c were also upregulated ( P<0.01).10 µmol/L CAP significantly attenuated these effects induced by ischemia reperfusion injury,levels of LVDP and infarct size at the end of reperfusion were significantly improved( P<0.01),nevertheless levels of LVEDP and MDA at the end of reperfusion and LDH were down-regulated markedly ( P<0.01),the content of caspase-3 and cytochrome c were also decreased ( P<0.01). CONCLUSION: These results demonstrate that CAP can suppresses cell apoptosis and necrosis,and alleviate heart function and cell survival from ischemia reperfusion injury through attenuating mitochondrial oxidative stress.

Robust Strategy for Crafting Li5Cr7Ti6O25@CeO2 Composites as High-Performance Anode Material for Lithium-Ion Battery.

A facile strategy was developed to prepare Li5Cr7Ti6O25@CeO2 composites as a high-performance anode material. X-ray diffraction (XRD) and Rietveld refinement results show that the CeO2 coating does not alter the structure of Li5Cr7Ti6O25 but increases the lattice parameter. Scanning electron microscopy (SEM) indicates that all samples have similar morphologies with a homogeneous particle distribution in the range of 100-500 nm. Energy-dispersive spectroscopy (EDS) mapping and high-resolution transmission electron microscopy (HRTEM) prove that CeO2 layer successfully formed a coating layer on a surface of Li5Cr7Ti6O25 particles and supplied a good conductive connection between the Li5Cr7Ti6O25 particles. The electrochemical characterization reveals that Li5Cr7Ti6O25@CeO2 (3 wt %) electrode shows the highest reversibility of the insertion and deinsertion behavior of Li ion, the smallest electrochemical polarization, the best lithium-ion mobility among all electrodes, and a better electrochemical activity than the pristine one. Therefore, Li5Cr7Ti6O25@CeO2 (3 wt %) electrode indicates the highest delithiation and lithiation capacities at each rate. At 5 C charge-discharge rate, the pristine Li5Cr7Ti6O25 only delivers an initial delithiation capacity of ∼94.7 mAh g-1, and the delithiation capacity merely achieves 87.4 mAh g-1 even after 100 cycles. However, Li5Cr7Ti6O25@CeO2 (3 wt %) delivers an initial delithiation capacity of 107.5 mAh·g-1, and the delithiation capacity also reaches 100.5 mAh g-1 even after 100 cycles. The cerium dioxide modification is a direct and efficient approach to improve the delithiation and lithiation capacities and cycle property of Li5Cr7Ti6O25 at large current densities.

Facile Synthesis of Carbon-Coated Spinel Li4Ti5O12/Rutile-TiO2 Composites as an Improved Anode Material in Full Lithium-Ion Batteries with LiFePO4@N-Doped Carbon Cathode.

The spinel Li4Ti5O12/rutile-TiO2@carbon (LTO-RTO@C) composites were fabricated via a hydrothermal method combined with calcination treatment employing glucose as carbon source. The carbon coating layer and the in situ formed rutile-TiO2 can effectively enhance the electric conductivity and provide quick Li+ diffusion pathways for Li4Ti5O12. When used as an anode material for lithium-ion batteries, the rate capability and cycling stability of LTO-RTO@C composites were improved in comparison with those of pure Li4Ti5O12 or Li4Ti5O12/rutile-TiO2. Moreover, the potential of approximately 1.8 V rechargeable full lithium-ion batteries has been achieved by utilizing an LTO-RTO@C anode and a LiFePO4@N-doped carbon cathode.

A high-throughput microtiter plate assay for the discovery of active and enantioselective amino alcohol-specific transaminases.

Chiral vicinal amino alcohols are important chiral building blocks and intermediates in the pharmaceutical industry. The transaminase (TAm) catalyzed kinetic resolution of racemic amino alcohols provides a straightforward approach to access these important compounds. This study describes the development of a novel microtiter plate assay to screen vicinal amino alcohol-specific TAms using a tetrazolium red-based colorimetric assay to monitor the rate of α-hydroxy ketone formation at 510 nm. This approach is the first to determine the Michaelis-Menten parameters for a recombinant TAm (PpbauA) from Pseudomonas putida NBRC14164. The corresponding Vmax and KM values for both enantiomers of 2-amino-1-propanol and 2-amino-1-butanol were obtained, and the calculated kinetic E-factors of PpbauA toward 2-amino-1-propanol and 2-amino-1-butanol are 3 (S) and 6 (R), respectively. The method is sensitive and exhibits low level background coloration. Moreover, this method can be used to detect transaminase activity and enantioselectivity toward amino alcohols in a high-throughput format. Additionally, this simple method is compatible with the most widely used (R)- and (S)-selective transaminases and may be a broadly applicable tool for screening transaminases from a transaminase mutant library.

Characterization of Four New Distinct ω-Transaminases from Pseudomonas putida NBRC 14164 for Kinetic Resolution of Racemic Amines and Amino Alcohols.

Four uncharacterized ω-transaminases (ωTAs) from Pseudomonas putida NBRC 14164 have been identified and cloned from the pool of fully sequenced genomes. The genes were functionally expressed in Escherichia coli BL21, and the enzymes were purified and characterized. Four TAs showed highly (S)-selective ωTA activity and converted (S)-α-methylbenzylamine and pyruvate to acetophenone and L-Ala. The maximum activity of cloned enzymes was in the pH range of 8.0-8.5 (Pp36420), 8.5-9.5 (Pp21050), 9.0-9.5 (PpspuC), and 9.5-10.5 (PpbauA), and the optimal temperatures were at 35 °C (Pp36420, Pp21050, and PpspuC) and 50 °C (PpbauA), respectively, with K M of 161.3 mM (Pp21050), 136.7 mM (PpbauA), 398.5 mM (Pp36420), and 130.9 mM (PpspuC) and yielding a catalytic efficiency k cat/K M of 0.015, 0.003, 0.012, and 0.023 mM-1 s-1. Several racemic amines and amino alcohols were resolved by the cloned ωTAs; perfect conversions (48-50 %) were obtained by at least one enzyme, and the residual substrates were left with 97-99 % ee. Kinetic resolution of racemic phenylglycinol was done with PpspuC in a 100-mL scale. Enaniomeric excess of (S)-phenylglycinol reached 99 % with 45 % isolated yield. The high enantioselectivity and large substrate spectra of the cloned PpTAs showed an attractive potency for biotechnology application in production of chiral amines and amino alcohols.

Wedelolactone metabolism in rats through regioselective glucuronidation catalyzed by uridine diphosphate-glucuronosyltransferases 1As (UGT1As).

BACKGROUND: Wedelolactone (WEL), a medicinal plant-derived coumestan, has been reported to exhibit a diverse range of pharmacological activities. However, the metabolism and disposition of WEL remain unexplored. PURPOSE: The present study aims to investigate the metabolism of WEL in rats and identify the enzymes responsible for forming major WEL metabolites. METHODS: Plasma, urine, feces, and bile samples were collected before and after 50 mg/kg WEL was orally administered to rats. Metabolites were profiled by ultrahigh performance liquid chromatography/quadrupole time-of-flight mass spectrometry and identified by high-performance liquid chromatography-solid-phase extraction-nuclear magnetic resonance spectroscopy. The in vitro WEL glucuronidation activities of human liver microsomes, human kidney microsomes, human intestine microsomes, and 12 recombinant human uridine diphosphate-glucuronosyltransferase (UGT) isoforms were screened. Molecular docking simulation of the interaction between WEL and UGT1A9 was conducted. RESULTS: WEL underwent extensive metabolism, and 17 metabolites were identified. The major metabolic pathways observed were glucuronidation and methylation. Glucuronic acid was preferentially introduced into 5-OH, whereas no obvious regioselectivity was observed in the methylation of 11-OH and 12-OH. Multiple UGTs, including UGT1A1, UGT1A3, UGT1A6, UGT1A7, UGT1A8, UGT1A9, and UGT1A10, were involved in forming WEL glucuronides and O-methylated WEL glucuronides. CONCLUSION: The extensive glucuronidation and methylation is responsible for the low oral bioavailability of WEL in rats. UGT1A1 and UGT1A9 were the major enzymes involved in the glucuronidation of WEL and O-methylated WEL. Molecular docking studies revealed that 5-OH was accessible to the catalytic domain of UGT1As; therefore, 5-OH exhibited a high probability of glucuronidation.

Antitussive, expectorant, and anti-inflammatory activities of four caffeoylquinic acids isolated from Tussilago farfara.

CONTEXT: The flower bud of Tussilago farfara L. (Compositae) (FTF) is one of the traditional Chinese medicinal herbs used to treat cough, phlegm, bronchitic, and asthmatic conditions. OBJECTIVE: The objective of this study is to isolate four caffeoylquinic acids from the ethyl acetate extract (EtE) of FTF and to evaluate their antitussive, expectorant, and anti-inflammatory activities. MATERIALS AND METHODS: The structures of compounds 1-4 isolated from EtE were determined by spectral analysis. Mice were orally treated with these compounds and their mixture (in a ratio of 5:28:41:26 as in EtE) at doses of 10 and 20 mg/kg once daily for 3 d. The antitussive and expectorant activities were evaluated separately with the ammonia liquor-induced model and the phenol red secretion model. The anti-inflammation activity was evaluated using leukocyte count in the bronchoalveolar lavage fluid after ammonia liquor-induced acute airway inflammation. RESULTS: The four compounds were identified as chlorogenic acid (1), 3,5-dicaffeoylquinic acid (2), 3,4-dicaffeoylquinic acid (3), and 4,5-dicaffeoylquinic acid (4). All compounds, especially compound 4 (58.0% inhibition in cough frequency), showed a significant antitussive effect. However, the mixture was the most effective to inhibit the cough frequency by 61.7%. All compounds also showed a significant expectorant effect, while compound 2 was the most potent to enhance the phenol red secretion by 35.7%. All compounds significantly alleviated inflammation, but compound 4 showed the strongest effect to inhibit the leukocytosis by 49.7%. DISCUSSION AND CONCLUSION: The caffeoylquinic acids and their mixture, exhibiting significant antitussive, expectorant, and anti-inflammatory effects, could be considered as the main effective ingredients of FTF, and they may act in a collective and synergistic way.