Co-Crystals of Resveratrol and Polydatin with L-Proline: Crystal Structures, Dissolution Properties, and In Vitro Cytotoxicities.

Resveratrol (RSV) and polydatin (PD) have been widely used to treat several chronic diseases, such as atherosclerosis, pulmonary fibrosis, and diabetes, among several others. However, their low solubility hinders their further applications. In this work, we show that the solubility of PD can be boosted via its co-crystallization with L-proline (L-Pro). Two different phases of co-crystals, namely the RSV-L-Pro (RSV:L-Pro = 1:2) and PD-L-Pro (PD:L-Pro = 1: 3), have been prepared and characterized. As compared to the pristine RSV and PD, the solubility and dissolution rates of PD-L-Pro in water (pH 7.0) exhibited a 15.8% increase, whereas those of RSV-L-Pro exhibited a 13.8% decrease. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay of pristine RSV, PD, RSV-L-Pro, and PD-L-Pro against lung cancer cell line A549 and human embryonic kidney cell line HEK-293 indicated that both compounds showed obvious cytotoxicity against A549, but significantly reduced cytotoxicity against HEK-293, with PD/PD-L-Pro further exhibiting better biological safety than that of RSV/RSV-L-Pro. This work demonstrated that the readily available and biocompatible L-Pro can be a promising adjuvant to optimize the physical and chemical properties of RSV and PD to improve their pharmacokinetics.

Cyclodextrin-based host-guest complexes loaded with regorafenib for colorectal cancer treatment.

The malignancy of colorectal cancer (CRC) is connected with inflammation and tumor-associated macrophages (TAMs), but effective therapeutics for CRC are limited. To integrate therapeutic targeting with tumor microenvironment (TME) reprogramming, here we develop biocompatible, non-covalent channel-type nanoparticles (CNPs) that are fabricated through host-guest complexation and self-assemble of mannose-modified γ-cyclodextrin (M-γ-CD) with Regorafenib (RG), RG@M-γ-CD CNPs. In addition to its carrier role, M-γ-CD serves as a targeting device and participates in TME regulation. RG@M-γ-CD CNPs attenuate inflammation and inhibit TAM activation by targeting macrophages. They also improve RG's anti-tumor effect by potentiating kinase suppression. In vivo application shows that the channel-type formulation optimizes the pharmacokinetics and bio-distribution of RG. In colitis-associated cancer and CT26 mouse models, RG@M-γ-CD is proven to be a targeted, safe and effective anti-tumor nanomedicine that suppresses tumor cell proliferation, lesions neovascularization, and remodels TME. These findings indicate RG@M-γ-CD CNPs as a potential strategy for CRC treatment.

Enhancing the Physiochemical Properties of Puerarin via L-Proline Co-Crystallization: Synthesis, Characterization, and Dissolution Studies of Two Phases of Pharmaceutical Co-Crystals.

Puerarin (PUE) is a Chinese traditional medicine known to enhance glucose uptake into the insulin cells to downregulate the blood glucose levels in the treatment of type II diabetes. Nevertheless, the bioavailability of pristine PUE is limited due to its poor solubility and low intestinal permeability. In this work, we demonstrate that the solubility of PUE can be significantly enhanced via its co-crystallization with L-Proline (PRO). Two crystalline phases, namely, the solvate-free form [PUE][PRO] (I) and the solvated form [PUE]2[PRO]∙EtOH∙(H2O)2 (II) are isolated. These two phases are characterized by single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Fourier-transformed infrared (FT-IR) spectra, nuclear magnetic resonance (NMR), and thermogravimetric analysis in association with differential scanning calorimetry (TGA-DSC). The solubility and dissolution rate of both I and II in water, gastrointestinal tract at pH 1.2, and phosphate buffer at pH 6.8 indicates a nearly doubled increase as compared to the pristine PUE. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay of pristine PUE, I and II against murine colon cancer cell lines CT-26 and human kidney cell lines HEK-293 indicated that neither compound exhibits obvious cytotoxicity after 24 h. This work showcases that the readily available and biocompatible PRO can be a promising adjuvant to enhance the physicochemical properties of PUE toward orally administered drug formulation with improved pharmacokinetics.

Enhanced antitumour effect for hepatocellular carcinoma in the advanced stage using a cyclodextrin-sorafenib-chaperoned inclusion complex.

Hepatocellular carcinoma (HCC) is a hypervascular tumour characterized by tumour-driven neovascularization. The degrees of blood oxygen saturation (DBOS), microvessel density (MVD) and tumour size (TS) are indicators in identifying the development stage of HCC. Herein, we proposed an HCC staging model using HepG2 tumour-bearing mice based on DBOS, MVD and TS. According to the patterns of these three criteria, HCC was classified into four stages: early, intermediate, advanced and end stages. The advanced stage was characterized by MVD of 50-90 (number per mm2), DBOS of 12-16% and TS of 250-600 mm3, which poses a critical challenge in HCC therapy. In order to efficiently control and treat HCC in the advanced stage, we developed a cyclodextrin (CD)-based chaperoned inclusion complex using Sorafenib (Sor), ß-CD and γ-CD (SCD) via the co-crystallization method. The structural study manifested that CDs could encapsulate Sor with the hydrophobic cavities at a 1 : 1 stoichiometry ratio. The crystallographic analysis indicated that Sor-ß-CD presented a diagonal stacking pattern, while Sor-γ-CD possessed a channel-type structure. The resultant chaperoned inclusion complexes significantly improved the solubility, dissolution rate and drug release of Sor, leading to superior pharmacokinetics, biodistribution and biosafety through oral administration. The antitumour effect was then evaluated on a mouse model with advanced HCC through oral administration and intratumour injection. The treatment involving the oral administration of SCDs showed a promising therapeutic effect on advanced HCC, which efficiently blocked angiogenesis and inhibited tumour progression. For the treatments using intratumour injections, only Sor-γ-CD exhibited a satisfactory anti-tumour effect with reduction in TS, MVD and DBOS. The enhanced therapeutic performance of Sor-γ-CD was attributed to its channel-type structure, which had an impact on the dissociation and release of the drug. Thus, Sor-γ-CD can be used as a potential pro-drug for clinical medicine and basic research to treat HCC.

Evaluation of molecular chaperone drug function: Regorafenib and ß-cyclodextrins.

Regorafenib (RG) was an oral multi-kinase inhibitor with poor water solubility. In order to enhance the drug's solubility, dissolution and bioavailability, the binary molecular chaperone drug between RG and ß-cyclodetrin (ß-CD) had prepared by co-crystallization. The structure of RG-ß-CD was characterized by thermal analysis, powder X-ray diffraction, infrared spectroscopy and nuclear magnetic resonance. Phase-solubility study revealed the higher solubility and complexing ability of ß-CDwith RG.The solubility and dissolution of RG-ß-CD was significantly enhanced in pH 1.2 medium, pH 6.8 PBS buffer solution and distilled water compared to RG. In vivo distribution and antitumor studies revealed that the bioavailability of RG-ß-CD was increased when ß-CD mated with RG. Therefore, these findings could provide a suitable pharmaceutical dosage to enhanced therapeutic activity.

A new reaction between common compounds: lead oxide reacts with formaldehyde.

We show here a new reaction between lead(II) oxide and formaldehyde aqueous solution, which has been overlooked all along. The special structure of the new substance (PbCH2O2) and the DFT calculations suggest a diol-mechanism, which not only informs people about the corrosive nature of HCHO toward Pb and PbO, but also leads us to discover some new reactions between a variety of vicinal diol-type molecules and PbO. The reaction is further highlighted because of its potential application in detection and treatment of formaldehyde-containing wastewaters.

Multifunctional cationic polymer decorated and drug intercalated layered silicate (NLS) for early gastric cancer prevention.

A multifunctional compound that can prevent early gastric cancer is produced by intercalating 3.20% and 1.64% of 5-FU into the interlayer of montmorillonite (MMT) and attapulgite (At), respectively. A low molecular weight cationic polymer, polyethylenimine (PEI1200), is incorporated into the surface of the 5-FU-MMT and 5-FU-At to form the multifunctional layered silicate (NLS). The chemical structure and surface morphology of the NLS are characterized and the model drug of 5-FU is intercalated into the MMT and At. The cell viability determined by the MTT assay on the BGC-823 cell lines show that over 80% of the cells are live under the experimental conditions. The PEI-5-FU-MMT and PEI-5-FU-At can carry the report gene to the BGC-823 and COS-7 cell lines efficiently. Western blotting assay shows that the pTrail protein of the BGC-823 cell lines treated with PEI-5-FU-MMT/pTrail and PEI-5-FU-At/pTrail is up-regulated, whereas the cFLIP protein is down-regulated at 48 h compared to free 5-FU, PEI1200, MMT, and At, providing evidence that the NLS can increase the sensitivity of pTrail gene and improve the effects of pTrail gene therapy. Moreover, the Helicobacter pylori (HP) bacteria are adsorbed and immobilized efficiently on the surface of the NLS according to the LIVE/DEAD(®) BacLight™ Bacterial Viability Kit in the confocal fluorescence analysis. The histochemical analyses provide evidence that NLS/pTrail can prevent early gastric mucosa effectively.

A New Diagnostic System for Detection of 'Candidatus Liberibacter asiaticus' Infection in Citrus.

In this study, two polyclonal antibodies were produced against the Omp protein of 'Candidatus Liberibacter asiaticus'. First, omp genes were sequenced to exhibit 99.9% identity among 137 isolates collected from different geographical origins. Then, two peptides containing the hydrophobic polypeptide-transport-associated (POTRA) domain and ß-barrel domain, respectively, were identified on Omp protein. After that, these two peptides were overexpressed in Escherichia coli and purified by affinity chromatography to immunize the white rabbits. Finally, the antiserum was purified by affinity chromatography. The two Omp antibodies gave positive results (0.454 to 0.633, 1:1,600 dilution) in enzyme-linked immunosorbent assay against 'Ca. L. asiaticus'-infected samples collected from different geographical origins but revealed negative results against other pathogen-infected, nutrient-deficient and healthy samples. The antibody against the POTRA domain of Omp protein could detect 'Ca. L. asiaticus' in 45.7% of the symptomatic samples compared with a 56.2% detection rate with a polymerase chain reaction assay. These new antibodies will provide a very useful supplement to the current approaches to 'Ca. L. asiaticus' detection and also provide powerful research tools for tracking distribution of this pathogen in vivo.

[Synthesis of a supermolecular nanoparticle γ-hy-PC/Ada-Dox and its antitumor activity].

OBJECTIVE: To synthesize a (2-Hydroxypropyl)-γ-cyclodextrin-polyethylenimine/adamantane-conjugated doxorubicin (γ-hy-PC/Ada-Dox) based supramolecular nanoparticle with host-guest interaction and to identify its physicochemical characterizations and antitumor effect. METHODS: A novel non-viral gene delivery vector γ-hy-PC/Ada-Dox was synthesized based on host-guest interaction. 1H-NMR, NOESY, UV-Vis, XRD and TGA were used to confirm the structure of the vector. The DNA condensing ability of complexes was investigated by particle size, zeta potential and gel retardation assay. Cytotoxicity of complexes was determined by MTT assay in BEL-7402 and SMMC-7721 cells. Cell wound healing assay was performed in HEK293 and BEL-7404 cells. The transfection efficiency was investigated in HEK293 cells. H/E staining and cell uptake assay was performed in BEL-7402 cells. RESULTS: The structure of γ-hy-PC/Ada-Dox was characterized by 1H-NMR, NOESY, UV-Vis, XRD, TGA. The drug loading was 0.5% and 5.5%. Gel retardation assay showed that γ-hy-PC was able to completely condense DNA at N/P ratio of 2; 0.5% and 5.5% γ-hy-PC/Ada-Dox was able to completely condense DNA at N/P ratio of 3 and 4,respectively. The cytotoxicity of polymers was lower than that of PEI25KDa. The transfection efficiency of γ-hy-PC was higher than that of γ-hy-PC/Ada-Dox at N/P ratio of 30 in HEK293 cells; and the transfection efficiency was decreasing when Ada-Dox loading was increasing. Cell uptake assay showed that γ-hy-PC/Ada-Dox was able to carry drug and FAM-siRNA into cells. CONCLUSION: The novel vector γ-hy-PC/Ada-Dox has been developed successfully, which has certain transfection efficiency and antitumor activity.

Synergistic treatment of ovarian cancer by co-delivery of survivin shRNA and paclitaxel via supramolecular micellar assembly.

Non-viral gene-delivery platforms have been developed to co-deliver chemotherapeutics and siRNAs. The synergistic effects between shRNAs against survivin and Paclitaxel (PTX) using supramolecular micelles self-assembled from the host PEI-CyD (PC) composed of ß-cyclodextrin (ß-CyD) and polyethylenimine (PEI, Mw 600) and guest adamantine conjugated PTX (Ada-PTX) in combination cancer therapy are investigated. The Ada-PTX is encapsulated inside the core and shRNA sticks to the shell surface. The physicochemical properties of these supramolecular nanoparticles are favorable to cell uptake and intracellular trafficking. Moreover, PTX and shRNA simultaneously delivered to SKOV-3 cells lead to efficient reduction in the survivin and Bcl-2 expression as well as synergistic cell apoptotic induction in the in vitro study. In particular, co-delivery of survivin shRNA and PTX suppresses cancer growth more effectively than delivery of either paclitaxel or shRNA in ovarian cancer therapy.

Bupropion hydro-bromide propanol hemisolvate.

The title compound {systematic name: N-[1-(3-chloro-phen-yl)-1-oxopropan-2-yl]-tert-butanaminium bromide propanol hemisolvate}, C(13)H(19)ClNO(+)·Br(-)·0.5C(3)H(8)O, crystallizes with two independent bupropion hydro-bromide ion pairs and a solvent 1-propanol mol-ecule in the asymmetric unit. In both mol-ecules, the expected proton transfer from HBr to the amino group of the bupropion mol-ecule is observed, and intra- and inter-molecular N-H⋯Br hydrogen-bond inter-actions are formed. These inter-actions link the mol-ecules into hydrogen-bond dimers. The side chains of the two cations have slightly different orientations. The 1-propanol solvent mol-ecule is linked to a bromide ion by an O-H⋯Br hydrogen bond.

Crystal structure determination of new antimitotic agent bis(p-fluorobenzyl)trisulfide.

The purpose of this research was to investigate the physical characteristics and crystalline structure of bis(p-fluorobenzyl)trisulfide, a new anti-tumor agent. Methods used included X-ray single crystal diffraction, X-ray powder diffraction (XRPD), Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetric (DSC) and thermogravimetric (TG) analyses. The findings obtained with X-ray single crystal diffraction showed that a monoclinic unit cell was a = 12.266(1) A, b = 4.7757(4) A, c = 25.510(1) A, beta = 104.25(1) degrees ; cell volume = 1,448.4(2) A(3), Z = 4, and space group C2/c. The XRPD studies of the four crystalline samples, obtained by recrystallization from four different solvents, indicated that they had the same diffraction patterns. The diffraction pattern stimulated from the crystal structure data is in excellent agreement with the experimental results. In addition, the identical FT-IR spectra of the four crystalline samples revealed absorption bands corresponding to S-S and C-S stretching as well as the characteristic aromatic substitution. Five percent weight loss at 163.3 degrees C was observed when TG was used to study the decomposition process in the temperature range of 20-200 degrees C. DSC also allowed for the determination of onset temperatures at 60.4(1)-60.7(3) degrees C and peak temperatures at 62.1(3)-62.4(3) degrees C for the four crystalline samples studied. The results verified that the single crystal structure shared the same crystal form with the four crystalline samples investigated.