Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer's disease.

Previous studies have shown that berberine has neuroprotective effects against Alzheimer's disease, including antagonizing tau phosphorylation, and inhibiting acetylcholinesterase activity and neural cell apoptosis. However, its low bioavailability and adverse reactions with conventional administration limit its clinical application. In this study, we prepared berberine nanoliposomes using liposomes characterized by low toxicity, high entrapment efficiency, and biodegradability, and modified them with lactoferrin. Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency. We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer's disease established by injection of amyloid-beta 1-42 into the lateral ventricle. Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus, reduced tau over-phosphorylation in the cerebral cortex, and improved mouse behavior. These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer's disease.

Molecular Characterization of Phospholipase C in Infection Structure Differentiation Induced by Pear Fruit Surface Signals, Stress Responses, Secondary Metabolism, and Virulence of Alternaria alternata.

Fungal pathogens use plant surface physiochemical signals to trigger specific developmental processes. To assess the role of phospholipase C (PLC) in mediating plant stimuli sensing of Alternaria alternata, the function of three PLC genes was characterized by constructing ΔAaPLC mutants. Here we showed that fruit wax-coated surfaces significantly induced appressorium formation in A. alternata and mutants. Germination of ΔAaPLC mutants did not differ from the wild type. Deletion of AaPLC1 led to the decrease of appressorium formation and infected hyphae, but the degree of reduction varies between the different types of waxes, with the strongest response to pear wax. Appressorium formation and infected hyphae of the ΔAaPLC1 mutant on dewaxed onion epidermis mounted with pear wax (θ4) were reduced by 14.5 and 65.7% after 8 h incubation, while ΔAaPLC2 and ΔAaPLC3 formed the same infection hyphae as wild type. In addition, AaPLC1 mutation caused pleiotropic effects on fungal biological function, including growth deficiency, changes in stress tolerance, weakening of pathogenicity to the host, as well as destruction of mycotoxin synthesis. Both AaPLC2 and AaPLC3 genes were found to have some effects on stress response and mycotoxin production. Taken together, AaPLC genes differentially regulate the growth, stress response, pathogenicity, and secondary metabolism of A. alternata.

New insights into BMP9 signaling in liver diseases.

Bone morphogenetic protein 9 (BMP9) is a recently discovered cytokine mainly secreted by the liver and is a member of the transforming growth factor ß (TGF-ß) superfamily. In recent years, an increasing number of studies have shown that BMP9 is associated with liver diseases, including nonalcoholic fatty liver disease (NAFLD), liver fibrosis and hepatocellular carcinoma (HCC), and BMP9 signaling may play dual roles in liver diseases. In this review, we mainly summarized and discussed the roles and potential mechanisms of BMP9 signaling in NAFLD, liver fibrosis and HCC. Specifically, this article will provide a better understanding of BMP9 signaling and new clues for the treatment of liver diseases.

Pharmacokinetic studies of multi-bioactive components in rat plasma after oral administration of Xintiantai â extract and effects of guide drug borneol on pharmacokinetics.

Objective: To investigate the in vivo pharmacokinetic characteristics of 17 bioactive components including ginsenoside Rg1, Rb1, Rd, berberine, epiberberine, jatrorrhizine, palmatine, columbamine, coptisine, evodiamine, dehydroevodiamine, rutaecarpine, limonin, hyperin, curcumin, demethoxycurcumin and bisdemethoxycurcumin in rat plasma after oral administration of Xintiantai I extract powder (XI) and Xintiantai I without guide drug borneol extract powder (XI without borneol), and study the compatibility effects of guide drug borneol on the pharmacokinetics. Methods: A UHPLC-MS/MS method was established and fully validated for the comparative pharmacokinetics of 17 bioactive components. The pharmacokinetics parameters of 17 bioactive components after oral administration of XI and XI without borneol were calculated by the software of DAS 3.0 and intercompared. Results: The specificity, linearity, lower limit of quantification (LLOQ), precision, accuracy, extraction recovery rates, matrix effects, and stability of the UHPLC-MS/MS assay were good within the acceptance criteria from FDA guidelines. Guide drug borneol can significantly increase AUC of G-Rd, palmatine, hyperin, curcumin, demethoxycurcumin, bisdemethoxycurcumin and C max of 16 bioactive components except for dehydroevodiamine (P < 0.05), decrease T max of G-Rd, berberine, columbamin, coptisine, limonin and MRT of 17 bioactive components in XI group (P < 0.05). Conclusion: Guide drug borneol enhanced the absorption of G-Rd, palmatine, hyperin, curcumin, demethoxycurcumin and bisdemethoxycurcumin.

Discovery of potent inhibitors of human ß-tryptase from pre-equilibrated dynamic combinatorial libraries.

Pre-equilibrated dynamic combinatorial libraries based on acyl hydrazone interchange of peptide-derived hydrazides and di- and tri-aldehydes have been used to discover potent inhibitors with nanomolar affinities for ß-tryptase. To identify potent inhibitors the activity of the full library containing 95 members was compared with those of sub-libraries in which individual building blocks were missing. The most active library members contain a rigid central aromatic scaffold with three cationic peptide arms. The arms of the best inhibitors also contained a tailor-made GCP oxoanion binding motif attached to a lysine side chain. The most potent tri-armed hydrazones with peptide arms GKWR or GKWK(GCP) were shown to inhibit ß-tryptase (Kica. 10-20 nM) reversibly, non-competitively and selectively (compared to related serine proteases, e.g. trypsin and chymotrypsin), most likely by binding to the protein surface, also in agreement with molecular modelling calculations. These new inhibitors are one order of magnitude more efficient than related tetravalent inhibitors obtained from previous work on a split-mix-combinatorial library and were identified with significantly less effort, demonstrating the usefulness of this approach for the identification of enzyme inhibitors in general.

Comparison of starches from five plants of Sect. Stenophora Uline and Sect. Lasiophyton Uline of Dioscorea grown in China.

BACKGROUND: Dioscorea resources with vital medicinal and functional values are abundant in south-west regions of China, especially in Sichuan Province. However, the resource in this region has received less attention compared with that of the north. D. zingiberensis, D. collettii, D. kamoonensis cv. Emei and Jinfo, and D. melanophyma from Sichuan Province and Chongqing City were studied with regard to the most abundant carbohydrate (starch) to search for new medicinal and food resources. RESULTS: The starches were small round granules or small oval granules and large elongated granules, except D. zingiberensis starch granules, which were disc-like in shape. D. zingiberensis and D. collettii starches showed higher values in total starch content, water-binding capacity and infrared ratio of absorbance bands at 1047/1035 and 1047/1022 cm⁻¹. Differential scanning calorimetry analysis demonstrated a higher gelatinisation temperature required more energy during the gelatinisation process. D. zingiberensis and D. collettii starches showed higher resistant starch content of 724.0 and 693.2 g kg⁻¹, respectively, with lower hydrolysis index and estimation of glycaemic index. All the starches exhibited an A-type pattern except D. melanophyma starch, which showed a C-type pattern evaluated by X-ray diffraction. CONCLUSION: These results showed that the starches with their low hydrolysis index values possessed potential values as healthy food.

Enantiomerically pure [M(6)L(12)] or [M(12)L(24)] polyhedra from flexible bis(pyridine) ligands.

Coordination-driven self-assembly is one of the most powerful strategies to prepare nanometer-sized discrete (supra)molecular assemblies. Herein, we report on the use of two constitutionally isomeric BINOL-based bis(pyridine) ligands for this purpose. Upon coordination to Pd(II) ions these self-assemble into enantiomerically pure endo- and exo-functionalized hexa- and dodecanuclear metallosupramolecular spheres with a chiral skeleton depending on the substitution pattern of the BINOL core. These aggregates were characterized by NMR, MS, DLS, TEM, and EELS as well as ECD. Furthermore, experimental ECD data could be compared to those obtained from theoretical simulations using a simplified Tamm-Dancoff approximation to time-dependent DFT to rationalize the extraordinary high molar circular dichroisms. Despite the rotational freedom around the central aryl-aryl bond of these ligands, the self-assembly process happens completely selective in a "narcissistic" self-recognition manner.

Novel imidazole-functionalized cyclen cationic lipids: synthesis and application as non-viral gene vectors.

A series of novel 1,4,7,10-tetraazacyclododecanes (cyclen)-based cationic lipids bearing histidine imidazole group 10a-10e were synthesized. These amphiphilic molecules have different hydrophobic tails (long chain, cholesterol or α-tocopherol) and various type of linking groups (ether, carbamate or ester). These molecules were used as non-viral gene delivery vectors, and their structure-activity relationships were investigated. As expected, the imidazole group could largely improve the buffering capabilities comparing to cyclen. The liposomes formed from 10 and dioleoylphosphatidyl ethanolamine (DOPE) could bind and condense plasmid DNA into nanoparticles with proper size and zeta-potentials. Comparing with Lipofectamine 2000, the formed lipoplexes gave lower transfected cells proportion, but higher fluorescence intensity, indicating their good intracellular delivering ability. Furthermore, results indicate that transfection efficiency of the cationic lipids is influenced by not only the hydrophobic tails but also the linking group. The cyclen-based cationic lipid with α-tocopherol hydrophobic tail and an ester linkage could give the highest transfection efficiency in the presence of serum.

A new approach to inhibit human ß-tryptase by protein surface binding of four-armed peptide ligands with two different sets of arms.

A series of six new tetravalent ligands (1-6) with two different sets of arms bind to the surface of ß-tryptase, a tetrameric enzyme with an A(2)B(2) arrangement of its four monomers and two different binding sites on its protein surface (as suggested by a docking study). Besides proteinogenic amino acids also the guanidiniocarbonyl pyrrole cation (abbreviated as GCP), as an artificial arginine analog, was introduced into the arms of the ligands to investigate its influence on protein surface binding and enzyme inhibition. Furthermore, four ligands (7-10) with four identical arms also containing the GCP group were additionally synthesized to study the influence of the GCP moiety on the inhibition properties compared to related ligands previously identified by us in earlier work. The best ligand from this new series (RWKG)(2)(GCP-LFG)(2) (6) indeed contains the artificial GCP group and with a K(i)-value of 67 nM is two orders of magnitude more efficient than the analogous ligand (RWKG)(2)(RLFG)(2) (1) derived solely from proteinogenic amino acids. Hence, four-armed ligands with two different arms are indeed efficient inhibitors for ß-tryptase and the artificial GCP group can improve the binding affinity of this type of ligand to the protein, demonstrating the advantage of tailor-made binding motifs to increase affinity.

Low molecular weight PEI-based biodegradable lipopolymers as gene delivery vectors.

Non-viral gene vectors play an important role in the development of gene therapy. In this report, different hydrophobic chains were introduced into low molecular weight (LMW) PEI-based biodegradable oligomers to form a series of lipopolymers (LPs), and their structure-activity relationships were studied. Results revealed that the nine polymers can condense plasmid DNA well to form nanoparticles with appropriate sizes (120-250 nm) and positive zeta-potentials (+25-40 V). In vitro experiments were carried out and it was found that LP2 showed much higher transfection efficiency both in the presence and in the absence of serum under the polymer/DNA weight ratio of 0.8 in A549 cells.

Isolation, Purification, Characterization and Effect upon HepG2 Cells of Anemaran from Rhizome Anemarrhena.

The rhizome of Anemarrhena asphodeloides is used as food and traditional Chinese medicine for its hypoglycemic effect. The aim of this study was to investigate the isolation, purification and hypoglycemic activity of Anemaran as the active component. The influence factors (isolation duration, ratio of residuals to water and extracting times) during the isolation process were evaluated. The optimal conditions for NA and AA were extraction temperature 90ºC and 100ºC, duration 1h and 1.5 h, extraction time 3 and 3, and the solid-liquor ratio 1:20 and 1:15, respectively. Neutral and acid Anemaran (NA and AA) were isolated from the rhizome of Anemarrhena asphodeloides. Five fractions of NA-1, NA-2, NA-3, AA-1 and AA-2 were obtained after crude neutral and acid Anemaran purified through DEAE- 52 cellulose anion-exchange column. The characterizations of Anemaran and its different fractions were both analyzed by Fourier transform infrared spectroscopy (FT-IR) and scanning electron micrographs (SEM). Structural properties of different fractions were examined by FT-IR. Strong characteristic absorption peaks were observed at around 1744 cm(-1)and 1650 cm(-1) caused by the C=O group of uronic acids, and the band between 1440 cm(-1) and 1395 cm(-1) associated with the stretching vibration of C-O of galacturonic acid. Neither the crude neutral, nor the acid anemaran significantly inhibited the growth of HepG2 cells in-vitro, which indicated the low cytotoxicity of the anemaran. Furthermore, both neutral and acid anemaran showed hypoglycemic effect. The hypoglycemic effect of neutral anemaran was much higher than that of acid anemaran.

[Nitric oxide production in Malus hupehensis roots under waterlogging and the effects of exogenous NaNO3 on this production].

Taking two-year old Malus hupehensis as test material, this paper studied its root nitric oxide (NO) production under waterlogging, and the effects of exogenous NaNO3 on this production. Waterlogging for 3-9 days promoted the NO production significantly. Within the 12 days of waterlogging, the NO production, nitrite reductase (NR) and nitric oxide synthase (NOS) activities, and malondialchehyche (MDA) content in roots increased first, and decreased subsequently. Under waterlogging, the application of 10 mmol NaNO3 x L(-1) inhibited the increase of MDA content and NOS activity while improved the NR activity significantly. After applying NaNO3, the root NO production increased in the first three days, but decreased significantly after the 6th day.

Microdispensing system via the contacting method.

This paper presents the development of a microdispensing system based on a contacting method, with an aim to lowering production and maintenance cost. The liquid, to be dispensed, is brought into contact with the work piece, thus dispensing a droplet by making use of the adhesion force between the liquid and the work piece. A piezoelectric actuator is employed as the drive for the system to achieve high precision. The control of the system is accomplished with a PID controller; controlling the dispensing process and trajectory tracking.

Molecular logic gates and switches based on 1,3,4-oxadiazoles triggered by metal ions.

Organic molecular devices for information processing applications are highly useful building blocks for constructing molecular-level machines. The development of "intelligent" molecules capable of performing logic operations would enable molecular-level devices and machines to be created. We designed a series of 2,5-diaryl-1,3,4-oxadiazoles bearing a 2-(para-substituted)phenyl and a 5-(o-pyridyl) group (substituent X=NMe(2), OEt, Me, H, and Cl; 1a-e) that form a bidentate chelating environment for metal ions. These compounds showed fluorescence response profiles varying in both emission intensity and wavelength toward the tested metal ions Ni(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+), and Pb(2+) and the responses were dependent on the substituent X, with those of 1d being the most substantial. The 1,3,4-oxadiazole O or N atom and pyridine N atom were identified as metal-chelating sites. The fluorescence responses of 1d upon metal chelation were employed for developing truth tables for OR, NOR, INHIBIT, and EnNOR logic gates as well as "ON-OFF-ON" and "OFF-ON-OFF" fluorescent switches in a single 1,3,4-oxadiazole molecular system.

Anion binding of N-(o-methoxybenzamido)thioureas: contribution of the intramolecular hydrogen bond in the N-benzamide moiety.

N-(o-methoxybenzamido)thioureas (2 X/2 Y) are found to show an enhanced anion binding affinity with binding constants over 10(7) mol(-1) L orders of magnitude for AcO(-) and a redshifted absorption of the anion binding complexes in acetonitrile (MeCN) relative to those of N-benzamidothioureas (1) that bear no o-OMe in the N-benzamide moiety, despite the electron-donating character of o-OMe. Absorption of the anion-2 X/2 Y complex was shown to be of the same charge-transfer nature as that of the anion-1 complex, but its dependence on substituent X is interestingly influenced by the o-MeOHNC=O six-membered-ring intramolecular hydrogen bond identified in 2 X/2 Y. Such an intramolecular hydrogen bond is suggested to be responsible for the enhanced anion binding affinity. In the presence of this intramolecular hydrogen bond, the anion binding constant of 2 X was found to be independent of substituent X at the N-phenyl ring, as in the case of 1, whereas that of 2 Y showed an amplified dependence on substituent Y at the N'-phenyl ring, but to a lower extent than that of 1. A similar ring intramolecular hydrogen bond was purported to exist in 2 Za, 2 Zd, and 2 Ze, which bear NHMe, F, and Cl as the ortho substituent in the N-benzamide moiety. In terms of the current roles of thiourea in not only anion recognition and sensing but also organocatalysis and crystal engineering, the present finding would be of significance for a wider structural diversity of smart thiourea derivatives with predesigned functions.

Anion-triggered substituent-dependent conformational switching of salicylanilides. New hints for understanding the inhibitory mechanism of salicylanilides.

A series of salicylanilides (1a-h) bearing varied substituents at the 3'- or 4'-position of the anilino moiety (substituent = p-OCH3, p-CH3, m-CH3, H, p-Cl, m-Cl, p-CO2CH3, and p-CN) were synthesized. In acetonitrile all of the substituted salicylanilides 1a-h predominantly adopt the "closed-ring" conformation facilitated by a strong intramolecular OH...O=C hydrogen bond. In the presence of H2PO4-, the conformation of 1a-h was found to be modulated by the substituent. With our proposed proton-transfer fluorescence probing method, we were able to show that the conformation of 1a-f bearing a not highly electron-withdrawing substituent was switched to the "open-ring" form by H2PO4-, whereas 1h bearing a highly electron-withdrawing substituent, p-CN, remained in the "closed-ring" conformation. The significance of these findings for understanding, from a molecular structural point of view, the mechanism of salicylanilide-based inhibitors for inhibiting the protein tyrosine kinase epidermal growth factor receptor was discussed.