S-acylation of p62 promotes p62 droplet recruitment into autophagosomes in mammalian autophagy.

p62 is a well-characterized autophagy receptor that recognizes and sequesters specific cargoes into autophagosomes for degradation. p62 promotes the assembly and removal of ubiquitinated proteins by forming p62-liquid droplets. However, it remains unclear how autophagosomes efficiently sequester p62 droplets. Herein, we report that p62 undergoes reversible S-acylation in multiple human-, rat-, and mouse-derived cell lines, catalyzed by zinc-finger Asp-His-His-Cys S-acyltransferase 19 (ZDHHC19) and deacylated by acyl protein thioesterase 1 (APT1). S-acylation of p62 enhances the affinity of p62 for microtubule-associated protein 1 light chain 3 (LC3)-positive membranes and promotes autophagic membrane localization of p62 droplets, thereby leading to the production of small LC3-positive p62 droplets and efficient autophagic degradation of p62-cargo complexes. Specifically, increasing p62 acylation by upregulating ZDHHC19 or by genetic knockout of APT1 accelerates p62 degradation and p62-mediated autophagic clearance of ubiquitinated proteins. Thus, the protein S-acylation-deacylation cycle regulates p62 droplet recruitment to the autophagic membrane and selective autophagic flux, thereby contributing to the control of selective autophagic clearance of ubiquitinated proteins.

Pharmacokinetics, Tissue Distribution, and Druggability Prediction of the Natural Anticancer Active Compound Cytisine N-Isoflavones Combined with Computer Simulation.

Cytisine N-methylene-(5,7-dihydroxy-4'-methoxy)-isoflavone (CNF2) is a new compound isolated from the Chinese herbal medicine Sophora alopecuroides. Preliminary pharmacodynamic studies demonstrated its activity in inhibiting breast cancer cell metastasis. This study examined the pharmacokinetics, absolute bioavailability, and tissue distribution of CNF2 in rats, and combined computer-aided technology to predict the druggability of CNF2. The binding site of CNF2 and the breast cancer target human epidermal growth factor receptor-2 (HER2) were examined with molecular docking technology. Next, ACD/Percepta software was used to predict the druggability of CNF2 based on the quantitative structure-activity relationship (QSAR). Finally, a simple and effective HPLC method was used to determine plasma pharmacokinetics and tissue distribution of CNF2 in rats. Prediction and experimental results show that compared with the positive control HER2 inhibitor SYR127063, CNF2 has a stronger binding affinity with HER2, suggesting that its efficacy is stronger; and the structure of CNF2 complies with the Lipinski's Rule of Five and has good drug-likeness. The residence time of CNF2 in rats is less than 4 h, and the metabolic rate is relatively fast; But the absolute bioavailability of CNF2 in rats was 6.6%, mainly distributed in the stomach, intestine, and lung tissues, where the CNF2 contents were 401.20, 144.01, and 245.82 µg/g, respectively. This study constructed rapid screening and preliminary evaluation of active compounds, which provided important references for the development and further research of such compounds.

Antihyperlipidaemic effect of triterpenic acid-enriched fraction from Cyclocarya paliurus leaves in hyperlipidaemic rats.

CONTEXT: Cyclocarya paliurus (Batal) Iljinskaja (Juglandaceae) is an edible and medicinal plant; the leaves are used in Chinese folkloric medicine to treat dyslipidaemia and diabetes. OBJECTIVE: This study evaluates the antihyperlipidaemic potential of the triterpenic acid-enriched fraction (TAE) from C. paliurus and the underlying mechanism. MATERIALS AND METHODS: The hyperlipidaemic rats were induced by high fat diet for 6 weeks. After oral administration of TAE (200 and 400 mg/kg), the neutral fraction (150 and 300 mg/kg) and statin (4 mg/kg) to the hyperlipidaemic rats for 4 weeks, lipid profile and apolipoprotein (apoB48) level in plasma, and the expression levels of apoB48, microsomal triglyceride transfer protein (MTP), phosphorylation of mitogen-activated protein kinase (MAPK) and tumour necrosis factor α (TNF-α) in intestine were examined. The main constituents in the TAE were identified by HPLC-MS. RESULTS: TAE administration (400 mg/kg) decreased the levels of atherogenic lipids in serum and liver (p < 0.05) and increased serum high-density lipoprotein cholesterol by 19.7%. Furthermore, TAE treatment (200 and 400 mg/kg) decreased plasma apoB48 level by 15.3 and 19.5%, downregulated intestinal apoB48 and MTP expression levels (p < 0.05), and inhibited TNF-α expression by 36.2 and 56.2% and the phosphorylation level of MAPK by 8.8 and 13.2%, respectively. HPLC analysis revealed the presence of pentacyclic- and tetracyclic-triterpene acids in TAE. CONCLUSION AND DISCUSSION: These findings suggested that TAE possessed antihyperlipidaemic activity partially involved in the inhibitory effect on apoB48 overproduction, which may provide evidence about its potential role in ameliorating dyslipidaemia.

[Chemical constituents from barks of Nothopanax delavayi].

Eleven compounds were isolated and purified from the barks extract of Nothopanax delavayi and their structures were identified as serratagenic acid-3-O-alpha-L-arabinopyranosyl-28-O-beta-D-glucopyranosyl ester (1), serratagenic acid-3-0-alpha-L-arabi-nopyranosyl-28-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (2), serratagenic acid (3), serratagenic acid-3-O-alpha-L-arabinopyranoside (4), serratagenic acid-beta-O-beta-(2', 4'-O-diacetyl) -D-xylopyranosyl-28-O-[alpha-L-rhamnopy-ranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->46)-beta-D-glucopyranosyl] ester (5), serratagenic acid-3-O-alpha-(4'-O-acetyl)-L-arabino pyrano-syl-28-0- [-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester(6), serratagenic acid-3-O-alpha-(2'-O-acetyl)-L-arabinopyranosyl-28-O-[-alpha-L-rhamnopyranosyl- (1-->4) -beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester(7), serratagenic acid-3-0-beta-D-xylopyranosyl-28-O-[-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] ester (8), protocatechuic acid (9), ethyl caffeate (10) and caffeic anhydride (11) by physicochemical properties and spectroscopic data analysis. Among them, compounds 3-4 and 9-11 were firstly isolated from the genus Nothopanax, and compounds 5-8 were isolated from this plant for the first time.

[Alkaloids from bulbs of Lycoris radiata].

Ten Amaryllidaceae alkaloids were isolated from the bulbs of Lycoris radiata. Their structures were identified as oxovittatine (1), apohaemanthamine (2), 9-O-demethylhomolycorine N-oxide (3), incartine (4), ismine (5), 6-O-methylpretazettine (6), tazettine (7), ungeremine (8), homolycorine (9), and O-methyllycorenine (10) by spectroscopic data analyses. Compound 1 was a new natural product. Compounds 2 and 3 were reported form the genus Lycoris for the first time and compounds 4-6 were isolated form the title plant for the first time.

Two new phenolic glucosides from marine-derived fungus Aspergillus sp.

Two new phenolic glucosides, including a new O-glycoside (1) and a new C-glycoside (2), were isolated from a marine-derived fungus Aspergillus sp. The structures of new compounds were elucidated through interpretations of spectroscopic evidence and high-resolution electrospray ionization mass spectrometry. The hexose unit of 1 was identified as ß-D-glucose by comparison with an authentic sample via HPLC after acid hydrolysis and derivatization. All compounds were evaluated for their ability to inhibit LPS-induced NO production in RAW264.7 macrophages, but none of them displayed significant activity.

Rapid Screening of Active Components with Topoisomerase I Inhibitory Activity in Sophora alopecuroides L. Based on Ultrafiltration Coupled with UPLC-QTOF-MS.

BACKGROUND: Topoisomerase I (Topo I) is a key target of many antitumor drugs in vivo. Alkaloids in Sophora alopecuroides L. can reportedly inhibit Topo I activity, but the pharmacodynamic material basis has not yet been determined. OBJECTIVE: This study aimed to rapidly identify active components which inhibit Topo I in S. alopecuroides L. METHODS: Affinity ultrafiltration coupled with ultra-performance liquid chromatography-quadrupole time of flight-mass spectrometry (UF-UPLC-QTOF-MS) screening system based on Topo I protein was established to screen and isolate a total alkaloid fraction in S. alopecuroides L. Topo I inhibitory activity and anti-tumor proliferation activity of the screened components were evaluated, and their molecular mechanisms were studied. RESULTS: Six compounds that bound specifically to Topo I were obtained. Further screening showed that matrine, cytisine, and sophoridine presented higher inhibitory activity on Topo I and were able to inhibit the proliferation of breast cancer MDA-MB-468 cells with IC50 values of 9.40 ± 1.12 mM, 17.4 ± 2.20 mM, and 10.4 ± 1.37 mM, respectively. To the best of our knowledge, their dual molecular mechanisms against Topo I have not discussed to date. In this study, the following dual mechanisms are reviewed for the first time: (1) stabilization of the Topo I-DNA complex and (2) inhibition or blocking of Topo I binding to DNA. CONCLUSION: Matrine, cytisine, and sophoridine from S. alopecuroides L. were defined as the active components possessing Topo I inhibitory activity, and their pharmacological mechanism was confirmed, which provided an important base for further research and development of antitumor components from S. alopecuroides L.

Compounds DRG and DAG, Two Phenol Glycosides, Inhibit TNF-α-stimulated Inflammatory Response through Blocking NF-kB/AKT/JNK Signaling Pathways in MH7A Cells.

Fourteen constituents were recently isolated from the roots of Dendropanax dentiger with cyclooxygenase-2 (COX-2) inhibitory effects. However, the effect of 14 constituents on rheumatoid arthritis (RA) and their action mechanism remain unclear. The study aimed to explore the anti-RA effect and potential mechanism of these constituents in tumor necrosis factor α (TNF-α)-stimulated human RA fibroblast-like synoviocytes (MH7A cells). The cell viability, nitric oxide (NO) production, inflammatory cytokine levels, and protein expressions were measured by cell counting kit-8 (CCK-8), Griess reagent, ELISA, and Western blot assays, respectively. Results showed that 14 constituents (40 µM) have no cytotoxicity for MH7A cells. Among them, two phenols including 3,4-dimethoxyphenyl-1-O-α-L-rhamnopyranosyl-(1→6)-O-ß-D-glucopyranoside (DRG) and 3,4-dimethoxyphenol-ß-D-apiofuranosyl-(1→6)-ß-D-glucopyranoside (DAG) were shown to significantly inhibit the NO production with IC50 values of 5.25±0.34 and 5.35±0.31 µM, respectively. They also remarkably decreased the release of interleukin (IL)-2, 6, 8, and interferon (IFN)-γ, as well as prominently reduced the phosphorylation protein levels of p65, IkBα, AKT, and JNK at a concentration of 10 µM. Taken together, DRG and DAG could inhibit TNF-α-induced inflammatory response through blocking NF-kB/AKT/JNK signaling pathways in MH7A cells, thus could be promising against RA and other inflammation-related agents.

Root carbon and nutrient homeostasis determines downy oak sapling survival and recovery from drought.

The role of carbon (C) and nutrient uptake, allocation, storage and especially their interactions in survival and recovery of trees under increased frequencies and intensities of drought events is not well understood. A full factorial experiment with four soil water content regimes ranging from extreme drought to well-watered conditions and two fertilization levels was carried out. We aimed to investigate whether nutrient addition mitigates drought effects on downy oak (Quercus pubescens Willd.) and whether storage pools of non-structural carbohydrates (NSC) are modified to enhance survival after 2.5 years of drought and recovery after drought relief. Physiological traits, such as photosynthesis, predawn leaf water potential as well as tissue biomass together with pools and dynamics of NSC and nutrients at the whole-tree level were investigated. Our results showed that fertilization played a minor role in saplings' physiological processes to cope with drought and drought relief, but reduced sapling mortality during extreme drought. Irrespective of nutrient supply, Q. pubescens showed increased soluble sugar concentration in all tissues with increasing drought intensity, mostly because of starch degradation. After 28 days of drought relief, tissue sugar concentrations decreased, reaching comparable values to those of well-watered plants. Only during the recovery process from extreme drought, root NSC concentration strongly declined, leading to an almost complete NSC depletion after 28 days of rewetting, simultaneously with new leaves flushing. These findings suggest that extreme drought can lead to root C exhaustion. After drought relief, the repair and regrowth of organs can even exacerbate the root C depletion. We concluded that under future climate conditions with repeated drought events, the insufficient and lagged C replenishment in roots might eventually lead to C starvation and further mortality.

Spinel-Type (FeCoCrMnZn)3O4 High-Entropy Oxide: Facile Preparation and Supercapacitor Performance.

High-entropy oxides (HEOs) have attracted more and more attention because of their unique structures and potential applications. In this work, (FeCoCrMnZn)3O4 HEO powders were synthesized via a facile solid-state reaction route. The confirmation of phase composition, the observation of microstructure, and the analysis of crystal structure, distribution of elements, and valences of elements were conducted by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS), respectively. Furthermore, a (FeCoCrMnZn)3O4/nickel foam ((FeCoCrMnZn)3O4/NF) electrode was prepared via a coating method, followed by the investigation of its supercapacitor performance. The results show that, after calcining (FeCoCrMnZn)3O4 powders at 900 °C for 2 h, a single spinel structure (FCC, Fd-3m, a = 0.8399 nm) was obtained with uniform distribution of Fe, Co, Cr, Mn, and Zn elements, the typical characteristic of a high-entropy oxide. In addition, the mass specific capacitance of the (FeCoCrMnZn)3O4/NF composite electrode was 340.3 F·g-1 (with 1 M KOH as the electrolyte and 1 A·g-1 current density), which indicates that the (FeCoCrMnZn)3O4 HEO can be regarded as a prospective candidate for an electrode material in the field of supercapacitor applications.

Grain Growth Kinetics of 0.65Ca0.61La0.26TiO3-0.35Sm(Mg0.5Ti0.5)O3 Dielectric Ceramic.

The 0.65Ca0.61La0.26TiO3-0.35Sm(Mg0.5Ti0.5)O3[0.65CLT-0.35SMT] ceramic was prepared by the solid-state reaction method. The effects of sintering process on its microstructure and grain growth behavior were investigated. The Hillert model and a simplified Sellars model were established by linear regression, and the Sellars-Anelli model with a time index was established by using a nonlinear regression method. The results show that the grain size gradually increases with the increase of sintering temperature and holding time. Meanwhile, the sintering temperature has a more significant effect on the grain growth. The grain sizes of 0.65CLT-0.35SMT ceramic were predicted by the three models and compared with the experimentally measured grain size. The results indicate that for the 0.65CLT-0.35SMT ceramic, the Hillert model has the lowest prediction accuracy and the Sellars-Anelli model, the highest prediction accuracy. In this work, the Sellars-Anelli model can effectively predict the grain growth process of 0.65CLT-0.35SMT ceramic.

The chloroform extract of Cyclocarya paliurus attenuates high-fat diet induced non-alcoholic hepatic steatosis in Sprague Dawley rats.

BACKGROUND: Hepatic steatosis (HS) is the early stage of nonalcoholic fatty liver disease which is caused by impaired hepatic lipid homeostasis. Cyclocarya paliurus, an herbal tea consumed in China, has been demonstrated to ameliorate abnormal lipid metabolism for the treatment of metabolic diseases. PURPOSE: We aimed to investigate the regulative effect of chloroform extract from Cyclocarya paliurus (ChE) on treatment of HS, as well as key factors involved in hepatic lipid metabolism. STUDY DESIGN: Sprague Dawley rats were fed with high-fat diet (HFD) for 6 weeks to induce HS and treated with or without ChE by gavage for 4 weeks. METHODS: The body weight, relative liver weight and liver fat content were measured. Serum and liver total cholesterol, triglyceride and non-esterified fatty acids, as well as hepatic malonaldehyde levels were accessed by biochemical methods. Serum and liver TNF-α levels were quantified by ELISA kit. Histologic analysis and 1H-MRS study were performed to evaluate HS level. RT-PCR and Western blot were also applied to observe the expression changes of key factors involved in hepatic lipid intake, synthesis, utilization and export. RESULTS: ChE significantly decreased the rats' body weight, serum lipid and TNF-α level. ChE also reduced their relative liver weight, liver fat content, hepatic oxidative products and TNF-α level. Hepatic steatosis in HFD-fed rats was effectively regressed after 2-weeks administration of ChE. Moreover, ChE treatment remarkably reduced HFD-induced high expression level of fatty acid synthesis genes (including sterol-regulatory element-binding protein 1, acetyl-CoA carboxylase 1 and fatty acid synthase). However, it had no effect on mRNA expression of some genes involved in lipid uptake, ß-oxidation and lipid outflow. CONCLUSION: ChE exerted a promising regression effect on HS due to a reduced level of serum non-esterified fatty acids which might lead to a decrease in the amount of lipid taken in by the liver, as well as owing to the inhibition of hepatic lipid de novo synthesis to reduce liver lipid production.

[Microbial community structure of the alpine meadow under different grazing styles in Naqu prefecture of Tibet].

To clarify the effects of grazing styles on the soil microbial community in the alpine meadow, we explored the changes of soil microbial community structure in the alpine meadow located in Naqu district of Tibet Autonomous Region by analyzing the soil chemical properties and phospholipid fatty acids (PLFAs). The results showed that the contents of soil total organic carbon, total phosphate and nitrate nitrogen under the different grazing styles followed the trend of 7-year rest grazing > free grazing > grazing prohibition. Except for the ratio of fungal PLFAs/bacterial PLFAs, total PLFAs, the bacterial PLFAs, the fungal PLFAs, the gram negative bacterial and the gram positive bacterial PLFAs over the different grazing types were in the order of 7-year rest grazing > 5-year grazing prohibition > 7-year and 9-year grazing prohibition. The principal component analysis (PCA) presented that the first principal component (PC1 = 74.6%) was mainly composed of monounsaturated fatty acids, polyunsaturated fatty acids and branched fatty acids, and the second principal component (PC2 = 13.2%) was mainly composed of saturated fatty acids and some monounsaturated fatty acids. Total PLFAs content was significantly positively correlated with microbial biomass carbon content. Compared with grazing prohibition, fallow grazing was best for the alpine meadow in Naqu district, and free grazing with light intensity was good for the alpine meadow.

Sphingosine kinase 1/sphingosine 1-phosphate signalling pathway as a potential therapeutic target of pulmonary hypertension.

Pulmonary hypertension is characterized by extensive vascular remodelling, leading to increased pulmonary vascular resistance and eventual death due to right heart failure. The pathogenesis of pulmonary hypertension involves vascular endothelial dysfunction and disordered vascular smooth muscle cell (VSMC) proliferation and migration, but the exact processes remain unknown. Sphingosine 1-phosphate (S1P) is a bioactive lysophospholipid involved in a wide spectrum of biological processes. S1P has been shown to regulate VSMC proliferation and migration and vascular tension via a family of five S1P G-protein-coupled receptors (S1P1-SIP5). S1P has been shown to have both a vasoconstrictive and vasodilating effect. The S1P receptors S1P1 and S1P3 promote, while S1P2 inhibits VSMC proliferation and migration in vitro in response to S1P. Moreover, it has been reported recently that sphingosine kinase 1 and S1P2 inhibitors might be useful therapeutic agents in the treatment of empirical pulmonary hypertension. The sphingosine kinase 1/S1P signalling pathways may play a role in the pathogenesis of pulmonary hypertension. Modulation of this pathway may offer novel therapeutic strategies.