Bio-based epoxidized soybean oil branched cardanol ethers as compatibilizers of polybutylene succinate (PBS)/polyglycolic acid (PGA) blends.

Blending poly(butylene succinate) (PBS) with another biodegradable polymer, polyglycolic acid (PGA), has been demonstrated to improve the barrier performance of PBS. However, blending these two polymers poses a challenge because of their incompatibility and large difference of their melting temperatures. In this study, we synthesized epoxidized soybean oil branched cardanol ether (ESOn-ECD), a bio-based and environmentally friendly compatibilizer, and used it to enhance the compatibility of PBS/PGA blends. It was demonstrated that the terminal carboxyl/hydroxyl groups of PBS and PGA can react with ESOn-ECD in situ, leading to branching and chain extension of PBS and PGA. The addition of ESO3-ECD to the blend considerably diminished the dispersed phase of PGA. Specifically, in comparison to the PBS/PGA blend without a compatibilizer, the diameter of the PGA phase decreased from 2.04 µm to 0.45 µm after the addition of 0.7 phr of ESO3-ECD, and the boundary between the two phases became difficult to distinguish. Additionally, the mechanical properties of the blends were improved after addition of ESO3-ECD. This research expands the potential applications of these materials and promotes the use of bio-based components in blend formulations.

Activate the endogenous Cu2+ switch for Zn(DDC)2 liposomes conversion: Providing a safer and less toxic alternative in cancer therapy.

The ancient anti-alcohol drug disulfiram (DSF) has gained widespread attention for its highly effective anti-tumor effects in cancer treatment. Our previous studies have developed liposome of Cu (DDC)2 to overcome the limitations, like the poor water solubility. However, Cu (DDC)2 liposomes still have shown difficulties in severe hemolytic reactions at high doses and systemic toxicity, which have limited their clinical use. Therefore, this study aims to exploratively investigate the feasibility of using DSF or DDC in combination also can chelate Zn2+ to form zinc diethyldithiocarbamate (Zn (DDC)2). Furthermore, this study prepared stable and homogeneous Zn (DDC)2 liposomes, which were able to be released in the tumor microenvironment (TME). The released Zn (DDC)2 was converted to Cu (DDC)2 with the help of endogenous Cu2+-switch enriched in the TME, which has a higher stability constant compared with Zn (DDC)2. In other words, the Cu2+-switch is activated at the tumor site, completing the conversion of the less cytotoxic Zn (DDC)2 to the more cytotoxic Cu (DDC)2 for effective tumor therapy so that the Zn (DDC)2 liposomes in vivo achieved the comparable therapeutic efficacy and provided a safer alternative to Cu (DDC)2 liposomes in cancer therapy.

A new C19-diterpenoid alkaloid in Aconitum georgei Comber.

Nine diterpenoid alkaloids were isolated from Aconitum georgei Comber belonging to the genus Aconitum in Ranunculaceae family. Their structures were determinated by using HR-ESI-MS and 1 D/2D NMR spectra as geordine (1), yunaconitine (2), chasmanine (3), crassicauline A (4), forestine (5), pseudaconine (6), 14-acetylalatisamine (7), austroconitine B (8), and talatisamine (9). Among them, compound 1 is a previously undescribed aconitine-type C19-diterpenoid alkaloid, and compounds 3, and 5-9 have not previously been isolated from this species. The results of in vitro experiments indicated that new compound 1 possesses mild anti-inflammatory activity, which inhibited the production of NO in LPS-activated RAW 264.7 cells with an inhibition ratio of 29.75% at 50 µM.

Stable Atropine Loaded Film As a Potential Ocular Delivery System For Treatment Of Myopia.

PURPOSE: The objective of the present study was to prepare stable and high bioavailability ocular atropine loaded films (ATR-films) as potential ocular drug delivery systems for the treatment of myopia. METHODS: ATR-films were prepared by the solvent casting method and the physical properties of films were evaluated including thickness, water content, light transparency, disintegration time, and mechanical properties. FT-IR, DSC, XRD, TGA, AFM, and Raman spectroscopy were performed to characterize the film. The stability test was conducted under different conditions, such as high humidity, high temperature, and strong light. The pharmacokinetic study and irritation assessment were conducted in rabbits. The efficacy of ATR-films was evaluated by refraction and ocular biometry in myopia guinea pigs. RESULT: After optimizing the formulation, the resulting ATR-film was flexible and transparent with lower water content (8.43% ± 1.25). As expected, the ATR-film was stable and hydrolysate was not detected, while the content of hydrolysate in ATR eye drops can reach up to 8.1867% (limit: < 0.2%) in the stability study. The safety assessment both in vitro and in vivo confirmed that the ATR-film was biocompatible. Moreover, the bioavailability (conjunctiva 3.21-fold, cornea 2.87-fold, retina 1.35-fold, sclera 2.05-fold) was greatly improved compared with the ATR eye drops in vivo pharmacokinetic study. The pharmacodynamic study results showed that the ATR-film can slow the progress of form-deprivation myopia (~ 100 ± 0.81D), indicating that it has a certain therapeutic effect on form-deprivation myopia. CONCLUSION: The ATR-film with good stability and high bioavailability will have great potential for the treatment of myopia.

[Phenylpropanoid glycosides from Sophorae Tonkinensis Radix et Rhizoma].

Three phenylpropanoid glycosides were purified by extensive chromatographic techniques including column chromatography over microporous resin, MCI, diol, sephadex LH-20, reverse phase C_(18) from water-extracts of Sophorae Tonkinensis Radix et Rhizoma. Their planar structures were elucidated by combination of various spectroscopic method, such as IR, UV, MS, and NMR. The absolute configuration of aglycone was determined by quantum chemical calculations. Their structures were elucidated as(8R)-3-(4-hydroxyphenyl)-1-propanol-2-O-ß-D-glucopyranoside(1), kalopanaxin D(2),(E)-4-hydroxycinnamyl alcohol 4-O-[2'-O-ß-D-apiofuranosyl(1″→2')]-ß-D-glucopyranoside(3). Compound 1 was undescribed previously. Compounds 2 and 3 were firstly isolated from Sophora genus.

Toxicity Reduction and Efficacy Promotion of Doxorubicin in the Treatment of Breast Tumors Assisted by Enhanced Oral Absorption of Curcumin-Loaded Lipid-Polyester Mixed Nanoparticles.

Curcumin (CUR), a polyphenol derived from turmeric, exhibits anticancer and anti-inflammatory properties. However, it has poor water solubility, stability, and oral bioavailability. To overcome these limitations, lipid-polyester mixed nanoparticles (NPs) embedded in enteric polymer-EudragitL100-55(Eu) were formulated (CUR-NPs-Eu). NPs composed of mPEG-b-PCL have a hybrid core made up of middle chain triglyceride (MCT) and poly(ε-caprolactone) (PCL) for enhancing drug loading. The CUR-NPs with MCT content of 10% had a particle size of 121.2 ± 16.8 nm, ζ potential of -16.25 ± 1.38 mV, drug loading of 9.8%, and encapsulation efficiency of 87.4%. The transport of the CUR-NPs-Eu across Caco-2 monolayers is enhanced compared with CUR alone (1.98 ± 0.94 × 10-6 of curcumin versus 55.43 ± 6.06 × 10-6 cm/s of curcumin-loaded NPs) because of the non-disassociated nanostructure during absorption. The absolute bioavailability of CUR-NPs-Eu was 7.14%, which was drastically improved from 1.08% of the CUR suspension (CUR-Sus). Therefore, in the xenograft 4T1 tumor-bearing mice, increased drug accumulation in heart and tumor was noticed because of enhanced oral bioavailability of CUR. The chemosensitizing effect of CUR was attributed to its NF-κB reduction effect (148 ± 11.83 of DOX alone versus 104 ± 8.71 of combined therapy, ng/g tissue). The cardioprotective effect of CUR was associated with maintenance of cardiac antioxidant enzyme activity and down-regulation of NF-κB. This study provided a partial illustration of the mechanisms of chemosensitizing and cardioprotective effects of CUR utilizing the oral availability promotion effect brought by the NPs-Eu formulation. And these results further demonstrated that the capability of this NPs-Eu system in oral delivery of poorly soluble and poorly permeable drugs.

A new diterpenoid alkaloid from Aconitum hemsleyanum.

A new C19-diterpenoid alkaloid named hemsleyaline (1), along with fourteen known alkaloids (2-15), were isolated from the roots of Aconitum hemsleyanum Pritz. (Ranunculaceae), a herbal medicine in southwest China. Their structures were established on the basis of extensive spectroscopic analyses. Compound 1 showed mild cholinesterase inhibitory effect with IC50 value of 471 ± 9 µM.

Structure-activity relationship of coptis alkaloid bitterness inhibited by mPEG-PLLA / 中国中药杂志

Inhibition of bitterness is a significant measure to improve the compliance and clinical efficacy of traditional Chinese medicine(TCM) decoction. According to the characteristics of TCM decoction, such as high dispersion of bitterness components, multi-component bitterness superposition and strong instantaneous stimulation, the research group put forward a new strategy to inhibit bitterness in the early stage based on the self-assembly characteristics of amphiphilic substances in aqueous solution, in order to reduce the distribution of bitterness components in real solution and achieve the purpose of bitter-masking. It was found that the bitter-masking effect of amphiphilic substances was different on the bitter compounds of various structures. Therefore, it was speculated that there might be a certain relationship between the bitter inhibition effect and the substrate structure. In this paper, the interaction between mPEG-PLLA and five bitter alkaloids(bamatine, jatrorrhizine, berberine, epiberberine and coptisine) in Coptidis Rhizoma was studied to explore the effect of substrate structure on the inhibition of bitterness. The sensory test of volunteers was used to determine the bitter-masking effect of mPEG-PLLA on the decoction of Coptidis Rhizoma and its main bitter alkaloids. The molecular docking and molecular force field were applied to locate the bitter groups and the bitter-masking parts. The relationship between the bitter strength and the structure was analyzed by the surface electrostatic potential of the bitter alkaloids, and the correlation between the bitter-masking effect and the structural parameters of the bitter components was explored by factor analysis, so as to clarify the structure-activity relationship of mPEG-PLLA in masking the bitterness of coptis alkaloids. It was found that mPEG-PLLA had significant taste masking effect on the decoction of Coptidis Rhizoma and five alkaloids. The masking effect was obviously related to the structure of different alkaloids: the effect increased with the increase of the number of hydrogen donors, rotatable bonds, molecular weight, and hydrophobicity, and decreased with the increase of surface electrostatic potential, electrophilicity and binding energy with bitter receptors. In this study, the influence of alkaloid structure of Coptidis Rhizoma on the butter-masking effect of mPEG-PLLA was preliminarily elucidated, providing a scientific basis for better exerting the bitter-masking effect of amphiphilic block copolymers.

Phenylpropanoid glycosides from Sophorae Tonkinensis Radix et Rhizoma / 中国中药杂志

Three phenylpropanoid glycosides were purified by extensive chromatographic techniques including column chromatography over microporous resin, MCI, diol, sephadex LH-20, reverse phase C_(18) from water-extracts of Sophorae Tonkinensis Radix et Rhizoma. Their planar structures were elucidated by combination of various spectroscopic method, such as IR, UV, MS, and NMR. The absolute configuration of aglycone was determined by quantum chemical calculations. Their structures were elucidated as(8R)-3-(4-hydroxyphenyl)-1-propanol-2-O-β-D-glucopyranoside(1), kalopanaxin D(2),(E)-4-hydroxycinnamyl alcohol 4-O-[2'-O-β-D-apiofuranosyl(1″→2')]-β-D-glucopyranoside(3). Compound 1 was undescribed previously. Compounds 2 and 3 were firstly isolated from Sophora genus.

Rynchopeterine F, unique heterodimer of phenethanol-phenylacetyl linking with lactic acid from the medicinal insect Blaps rynchopetera.

A new heterodimer, rynchopeterine F (1), a new natural product, rynchopeterine G (2), and eleven known phenolics were isolated from Blap rynchopetera Fairmaire, a kind of medicinal insect utilized by the Yi and Bai Nationality in Yunnan Province of China. Their structures were established on the basis of extensive spectroscopic analyses (1D and 2D NMR, HR-MS) along with calculated electronic circular dichroism method. Rynchopeterine F was a unusual heterodimer of a 3,4-dihudroxy phenylethanol unit fused to a 3,4-dihudroxy phenylacetyl group through two ester bonds with lactic acid, and rynchopeterine G was a 3,4-dihudroxy phenylethanyl monoester succinate. Attributed to the adjacent dihydroxyl grops, compounds 1 and 2 exhibited significant anti-radical activity with an IC50 value of 3.52 and 7.83 µg/mL for DPPH radical-scavenging, similar with that of the positive controls, vitamin C, 6.92 µg/mL and rutin, 8.28 µg/mL.

A Comprehensive Preclinical Evaluation of Intravenous Etoposide Lipid Emulsion.

PURPOSE: Etoposide is one of the principal chemotherapeutic agents used for the treatment of small cell lung cancer (SCLC). There are some disadvantages of currently available etoposide injections (EI) such as low LD50, necessary dilution before clinical application, thus, etoposide lipid emulsion (ELE) was developed and expected to have a comparable or better effect on SCLC. METHODS: ELE was prepared through high-pressure homogenization method, and a series of evaluations such as encapsulation efficiency (EE%), in vitro release, stability studies, pharmacokinetics study, safety assessment and pharmacodynamic study were systematically performed. RESULTS: ELE had high EE% and good stability. Pharmacokinetics study revealed ELE had a longer T1/2 F compared with EI, which is in agreement with in vitro release in which ELE released slower than EI (EI released over 80% within 12 h, while ELE released 50%). Safety tests showed there was no hematology or significant tendency of accumulated toxicity, and LD50 of ELE was higher than EI. Furthermore, percentage of tumor inhibition (TI%) of ELE was comparable with EI in the same dose. CONCLUSIONS: Unlike EI, ELE could further increase the dose, which endowed etoposide with a greater potential for cytotoxic agent. LE is a promising delivery system for etoposide.

A chemo-photothermal synergetic antitumor drug delivery system: Gold nanoshell coated wedelolactone liposome.

In this study, an antitumor drug delivery system, gold nanoshell coated wedelolactone liposomes (AuNS-Wed-Lip), were designed and synthesized. In the drug delivery system, wedelolactone liposome and gold-nanoshell were linked by l-cysteine, which had been shown an effective nanocarrier for antitumor drug delivery, on-demand drug release, and phototherapy under near-infrared (NIR) light irradiation. It was capable of absorbing 780-850 nm NIR light and converting light energy to heat rapidly. The hyperthermia promoted wedelolactone release rapidly from the systems. The release amount of AuNS-Wed-Lip under NIR irradiation reached up to 97.34% over 8 h, achieving the on-demand drug release. Moreover, a high inhibition rate up to 95.73% for 143B tumor cells by AuNS-Wed-Lip upon laser irradiation at 808 nm was observed. The excellent inhibition efficacy was also displayed in vivo antitumor study with S180 tumor-bearing mice. The results demonstrated that AuNS-Wed-Lip, as an antitumor drug delivery system, achieved chemo-photothermal synergetic effect, which has great potential in cancer therapy.

Single-chain Antibody Against Reg4 Suppresses Gastric Cancer Cell Growth and Enhances 5-FU-induced Cell Death in vitro.

BACKGROUND: Regenerating islet-derived gene family member 4 (Reg4), a well-investigated growth factor in the regenerative pancreas, has recently been reported to be highly associated with a majority of gastrointestinal cancers. Pathological hyper-expression or artificial over-expression of Reg4 causes acceleration of tumor growth, migration, and resistance to chemotherapeutic 5-Fluorouracil (5-FU). Until now, no method has been successfully established for eliminating the effects of Reg4 protein. METHODS: This study reports the production of an engineered immunoglobin, a single-chain variable fragment (scFv-Reg4), to specifically bind Reg4 and block the bioactivity. The complementary-determining regions (CDRs) against Reg4 were assigned using MOE and ZDOCK servers. The binding affinity (KD) was determined by bio-layer interferometry (BLI). MKN45 and AGS cell proliferation was determined by Thiazolyl blue tetrazolium bromide (MTT) method and the cell apoptosis was detected by flow cytometry assay. RESULTS: The KD of scFv-Reg4 to Reg4 was determined to be 1.91×10-8. In MKN45 and AGS cell lines, scFv- Reg4 depressed Reg4-stimulated cell proliferation and the inhibitory rates were 27.7±1.5% and 17.3±2.6%, respectively. Furthermore, scFv significantly enhanced 5-FU-induced cell death, from 23.0±1.0% to 28.4±1.2% in MKN45 and 28.2±0.7% to 36.6±0.6% in AGS cells. Treatment with scFv alone could lyse cancer cells to a certain extent, but no significance has been observed. CONCLUSION: The single-chain antibody (scFv-Reg4) significantly inhibited gastric cancer cell proliferation and synergistically enhanced the lethal effect of 5-FU. Thus, traditional chemo-/radio- therapeutics supplemented with scFv-Reg4 may provide advances in the strategy for gastrointestinal cancer treatment.

Three new diterpenoid alkaloids isolated from Aconitum brevicalcaratum.

In the present study, three new aconitine-type diterpenoid alkaloids brochyponines A-C (1-3) were isolated from the roots of Aconitum brevicalcaratum. Their structures were established on the basis of extensive spectroscopic analyses (IR, HR-ESI-MS, and 1D and 2D NMR). The NMR data of salt form for compound 1 in CDCl3 were also measured.

Self-assembly synthesis of vapreotide­gold hybrid nanoflower for photothermal antitumor activity.

Based on the self-assembly properties of vapreotide acetate (Vap), one kind of novel vapreotide acetate­gold nanoflowers (Vap-AuNFs) was fabricated for the first time by biomimetic mineralization method using Vap as a template. The Vap-AuNFs possessed anisotropic structure with a large absorption cross-section, which were face-centered cubic crystalline, exhibiting a remarkable monodisperse, narrow size (154 nm) distribution and good stability in aqueous solution. The apparent anisotropy of the gold nanostructure with high molar extinction coefficient can cause significantly higher plasmon absorption of Vap-AuNFs in the near infrared (NIR) region compared with Au nanoparticles (AuNPs), so the nanocomplex can induce remarkably enhanced photothermal conversion efficiency under NIR light irradiation. Breathtakingly, Vap-AuNFs exhibited superior biocompatibilities compared to AuNPs, as well as enhanced Hela cells lethality under NIR irradiation. This novel method was simple, low cost and green for the design and preparation of anisotropic gold nanoflowers with outstanding NIR laser-induced local hyperthermia, highlighting their potential applications in biomedical fields.

New phenylpropanoids from Bulbophyllum retusiusculum.

Two new phenylpropanoids, retusiusines A (1) and B (2), and a pair of new phenylpropyl enantiomers, (±)-retusiusine C (3a and 3b), together with eight known compounds, dihydroconiferyl dihydro-p-coumarate (4), methyl 3-(4-hydroxyphenyl) propionate (5), 3-(4-hydroxyphenyl)-propanoic acid (6), dihydroferulic acid (7), methyl 3-(4-methoxyphenyl) propionate (8), 3-(3,4-dimethoxyphenyl)-2-propenal (9), trans-p-coumaric acid (10) and dihydroconiferyl alcohol (11), were isolated from the tubers of Bulbophyllum retusiusculum. The absolute configurations of the new compounds were determined by calculating their electronic circular dichroism (ECD), spectra and specific optical rotations and comparing the calculated values with the experimental data. Compound 2 exhibited potent antifungal activity against Candida albicans (16 µg/mL). Compound 3 showed moderate antibacterial activity against Bacillus subtilis (64 µg/mL).

Biopharmaceutical characters and bioavailability improving strategies of ginsenosides.

Deglycosylation is the most important gastrointestinal metabolism in which ginsenosides are split off from glycosyl moieties by the enzymes secreted from intestinal microflora, and two possible metabolic pathways of protopanaxdiol-type ginsenosides (PPD-type ginsenosides) and protopanaxtriol-type ginsenosides (PPT-type ginsenosides) have been concluded. The former is deglycosylated at C-3 and/or C-20, and transformed to protopanaxdiol (PPD). By comparison, the latter is deglycosylated at C-6 and/or C-20, and eventually transformed to protopanaxtriol (PPT) instead. The pharmacokinetic behavior of PPD-type ginsenosides and PPT-type ginsenosides is different, mainly in a faster absorption and elimination rate of PPT-type ginsenosides, but almost all of ginsenosides have a low oral bioavailability, which is relevant to the properties, the stability in the gastrointestinal tract, membrane permeability and the intestinal and hepatic first-pass effect of ginsenosides. Fortunately, its bioavailability can be improved by means of pharmaceutical strategies, including nanoparticles, liposomes, emulsions, micelles, etc. These drug delivery systems can significantly increase the bioavailability of ginsenosides, as well as controlling or targeting drug release. Ginsenosides are widely used in the treatment of various diseases, the most famous one is the Shen Yi capsule, which is the world's first clinical application of tumor neovascularization inhibitors. Hence, this article aims to draw people's attention on ocotillol-type ginsenosides, which have prominent anti-Alzheimer's disease activity, but have been overlooked previously, such as its representative compound-Pseudoginsenoside F11(PF11), and then provide a reference for the druggability and further developments of ocotillol-type ginsenosides by utilizing the homogeneous structure between dammarane-type ginsenosides and ocotillol-type ginsenosides.

Improving the antioxidant activity and enriching salvianolic acids by the fermentation of Salvia miltiorrhizae with Geomyces luteus.

The antioxidant activities and total phenolic content of fermented Salvia miltiorrhiza with fungus Geomyces luteus were investigated. The results revealed that G. luteus fermentation could significantly improve the antioxidant activity and total phenolic content of S. miltiorrhiza. The main antioxidant constituents were characterized by spectroscopic analysis as salvianolic acids. High-performance liquid chromatography (HPLC) quantification also showed the enhanced content of salvianolic acid B after fermentation. The present study suggests that G. luteus fermentations are effective in the S. miltiorrhiza salvianolic acids' enrichment process.

Alkaloids with antioxidant activities from Aconitum handelianum.

A new C20-diterpenoid alkaloid handelidine (1) and twenty-seven known alkaloids (2-28) were isolated from the roots of Aconitum handelianum. Their structures were established on the basis of extensive spectroscopic analyses. The study indicated that denudatine-type C20-diterpenoid alkaloids with vicinal-triol system and benzyltetrahydroisoquinoline alkaloids exhibited significant antioxidant activities measured by three antioxidant test systems. The aconitine-type C19-diterpenoid alkaloids could serve as potential secondary antioxidants for their strong binding effects to metal ions.

A new flavone C-glycoside and a new bibenzyl from Bulbophyllum retusiusculum.

A new flavone C-glycoside, apigenin 6-C-α-arabinofuranosyl 8-C-α-arabinopyranoside (1) and a new bibenzyl, bulbotetusine (2), were isolated from the tubers of Bulbophyllum retusiusculum. Their structures were established on the basis of extensive spectroscopic analyses. The absolute configuration of 2 was determined by the comparison of experimental and calculated electronic circular dichroism. Compounds 1 and 2 showed no obvious cytotoxic activity against any five human tumour cell lines with IC50 values >40 µM.