Xiaoqiang Guo

Trans-resveratrol loaded chitosan nanoparticles modified with biotin and avidin to target hepatic carcinoma.

Conventional liver targeted system focuses on delivering drugs to liver, bringing toxicity on hepatic normal tissues. The purpose of this study is to construct a new system capable of specially targeting to hepatic carcinoma instead of the whole liver. Based on the fact that nanoparticles (NPs) bound with either biotin or avidin tend to accumulate in tumors and avidin-attached reagents were quickly eliminated from blood circulation and assembled in liver, trans-resveratrol loaded chitosan nanoparticles (CS-NPs), CS-NPs with the surface modified either by biotin (B-CS-NPs) or by both biotin and avidin (A-B-CS-NPs) were prepared and their physiochemical properties were investigated. The in vitro release profiles of the three NPs all conformed to bioexponential equation. Pharmacokinetic experiment indicated that A-B-CS-NPs rapidly assembled in liver after injection, with the highest liver targeting index of 2.70, while the modification of biotin attenuated the liver targeting ability of NPs. Inhibitory study on HepG2 cells declared that compared to trans-resveratrol solution and CS-NPs, both B-CS-NPs and A-B-CS-NPs significantly improved the anticancer activity. When incubated with HepG2 cells at high concentration for longer time, A-B-CS-NPs exhibited superior cytotoxicity than B-CS-NPs. This study exclaims that A-B-CS-NPs may be a potent drug delivery vector specially targeting to hepatic carcinoma.

Preparation, characterization, and cytotoxicity of various chitosan nanoparticles

Chitosan nanoparticles (CS-NPs) without drug loading have diverse biological activity. In this study, we prepared CS-NPs, CS-NPs solidified by different amount of glutaraldehyde, and CS-NPs modified with either biotin (B-CS-NPs) or biotin and avidin (ABCS-NPs) and examined their cytotoxicity on HepG2 cells. The morphology and size were measured by transmission electron microscopy and photon correction spectroscopy, respectively. The extent of solidification was validated by the approach of sonication. Biotin connect density on the surface of B-CS-NPs and A-B-CS-NPs was determined by biotin assay kit. The results showed that most of the NPs were round and theirmean sizes were all below 300 nm. Biotin connect density of B-CS-NPs and A-BCS-NPs was 2.18 ± 0.36 and 1.26 ± 0.11mol biotin/mol CS, respectively. At relatively low concentration, CS-NPs with higher extent of solidification exhibited more vigorous inhibitory effect against HepG2 cells than those without solidification. When NPs were incubated with cancer cells for 48 h, compared with CS-NPs, the anticancer activity of B-CS-NPs and A-B-CS-NPs was enhanced significantly (P > 0.05). In addition, A-B-CS-NPs showed superior cytotoxicity over B-CS-NPs. This study demonstrates that modification with biotin and avidin may be an efficient way in improving antitumor activity of CS-NPs against hepatic carcinoma.

JAK/STAT3 and Smad3 activities are required for the wound healing properties of Periplaneta americana extracts

Periplaneta americana extracts (PAEs) play a crucial role in skin wound healing. However, their molecular effects and signaling pathways in regenerating tissues and cells are not clear. In this study, we refined the PAE from Periplaneta americana to investigate the mechanisms underlying skin wound healing. The human keratinocyte line HaCaT was selected and a mouse model of deep second-degree thermal burn was established for in vitro and in vivo studies, respectively. PAE treatment induced the proliferation and migration of HaCaT cells and wound healing in the burn model. Furthermore, the effects of PAE on wound healing were found to depend on the Janus-activated kinase/signal transducer and activator of transcription 3 (JAK/STAT3) pathway and Smad3 activities, according to western blot analysis and immunohistochemical (IHC) assays in vitro and in vivo. Pretreatment with a STAT3 inhibitor blocked the cell proliferation and migration induced by PAE. The results indicate the wound-healing function of PAE via enhanced JAK/STAT3 signaling and Smad3 activities. Our studies provide a theoretical basis underlying the role of PAE in cutaneous wound healing.

Antioxidant activity of olive wine, a byproduct of olive mill wastewater.

Abstract Context Although olive mill wastewater (OMWW) is a good source of bioactive phenolic compounds, disposing OMWW is a serious environmental challenge. Production of wine via fermenting OMWW may be a promising alternative to deal with OMWW. However, whether or not olive wine from OMWW still reserves its original bioactivities remains unclear. Objective This study examines antioxidant activity of olive wine fermented from OMWW. Materials and methods Hydroxytyrosol in olive oil was determined by HPLC. Total flavonoid, total polyphenol and in vitro antioxidant activities were measured by spectrophotometry. Aged mice were intragastricly administered 7, 14 and 28 mL/kg olive wine consecutively for 30 d. Afterward, levels of malonaldehyde (MDA), protein carbonyl, reduced glutathione (GSH) and activity of superoxide dismutase (SOD) were assayed in mouse plasma and liver. Results Contents of hydroxytyrosol, total flavonoid and total polyphenol in olive wine were 0.14 ± 0.01, 0.29 ± 0.06 and 0.43 ± 0.03 mg/mL, respectively. The IC50 value of olive wine to scavenge DPPH and hydroxyl free radicals was 2.5% and 3.2% (v/v), respectively. Compared with the solvent control group, olive wine with a dose of 28 mL/kg remarkably lowered mouse MDA concentration in liver, and reduced protein carbonyl level in plasma (p < 0.05). Meanwhile, olive wine at doses of 7 and 28 mL/kg notably enhanced SOD activity in both mouse plasma and liver (p < 0.05). The beneficial effect on liver was superior to that of γ-tocopherol. Conclusion The study demonstrated that olive wine from OMWW has potential for treating oxidative stress-associated diseases.

4-Chloro­phenyl 2-oxo-2H-chromene-3-carboxyl­ate

In title compound, C16H9ClO4, the coumarin ring system is approximately planar [maximum deviation = 0.056 (1) Å] and is oriented with respect to the benzene ring at an angle of 22.60 (7)°. Intermolecular C—H⋯O hydrogen bonding is present in the crystal.

Modeling impacts of climate change on the geographic distribution of medicinal plant Fritillaria cirrhosa D. Don

Abstract Fritillaria cirrhosa D. Don is a renowned traditional Chinese medicine plant that is mainly distributed in the southeastern margin of the Qinghai–Tibet Plateau. The overexploitation in the recent years has led to a sharp decline of this undomesticated resource. Analyzing the impact of climate change on the geographic distribution of F. cirrhosa is meaningful for its conservation and domestication. In this study, the maximum entropy model (Maxent) was used to simulate the distribution of F. cirrhosa in relation to the current and future climatic conditions. The maximum temperature of the warmest month (Bio 5) and the precipitation of the warmest quarter (Bio 18) were the two most important bioclimatic variables determining the distribution of F. cirrhosa. Based on the predicted level of climatic warming, a further reduction of the geographic distribution of F. cirrhosa is to be expected. This study demonstrated the necessity and urgency of establishing more effective ways to protect the natural F. cirrhosa resources and developing artificial cultivation methodology.

Poria cocos (Schw.) Wolf 茯苓 (Fuling, Indian Bread)

Fuling, Poria cocos (Schw.) Wolf, is a saprophytic fungus that grows in diverse species of Pinus. It is a well-known traditional Chinese medicine (TCM) widely used in China and East Asian countries for its diuretic, sedative and tonic effects.

Deltaline from Delphinium delavayi Franch

The title compound [systematic name: 6β,10-dihydroxy-1α,14α,16β-trimethoxy-4-methyl-7β,8-(methylenedioxy)-20-ethylaconitan-6-yl acetate], C27H41NO8, is a C19-diterpenoid alkaloid and a major diterpenoid alkaloid component of the roots of Delphinium delavayi Franch. var. pogonanthum (Hand.-Mazz.) W. T. Wang. The molecule has a lycoctonine carbon-atom skeleton with four six-membered rings and three five-membered rings among; three of the six-membered rings adopt chair conformations with the fourth adopting a boat conformation while all of the five-membered rings exhibit envelope conformations. Intermolecular O—H⋯O hydrogen bonding is present in the crystal structure.

Proliferation and Differentiation of MC3T3-E1 Cells Cultured on Apatite-Coated Honeycomb Collagen

The purpose of this study was to develop a new biodegradable bone substitute materials consisting of synthesized hydroxyapatite (HAp) and Type I biodegradable honeycomb collagen sponge (HCS) composites. Apatite-coated Honeycomb collagen composite scaffolds (HAp-HCS) was fabricated and the proliferation and differentiation of MC 3T3-E1 cells were examined for the assessment of their biocompatibility. HAp was combined with Honeycomb Collagen Scaffolds(HCS) using a chemical method. MC 3T3-E1 cells were inoculated into the polystyrene cell culture dishes, HCS and HAp-HCS respectively. The proliferation was assessed using WST-8 assay. The results indicated that MC 3T3-E1 cells grown on the HAp-HCS composite scaffolds showed a higher proliferation rate and spread better than that on the HCS.The differentiation of MC 3T3-E1 cells were characterized by alkaline phosphatase activity. After being cultured in conditioned medium for 14 days, the alkaline phosphatase activities were assessed. The quantitative examination of alkaline phosphatase activity indicated that the cells cultured on the HAp-HCS expressed an activity level about 3 times higher than that on HCS at 14 d. The expression level of characteristic type&#8544;collagen , osteocalcin gene were evaluated using real-time PCR. The type&#8544;collagen gene of cells cultured on HAp-HCS composite scaffolds showed a higher expression level than that on the HCS at 14,21 d . Expression of the osteocalcin mRNA of cells cultured on HAp-HCS showed a higher expression level than that on HCS only at 14 d. The addition of hydroxyapatite in the HCS improved not only the proliferation but also the differentiation of preosteoblast cultured on them. The composite scaffolds showed good biocompatibility and bioactivity. These scaffolds would be promising in bone tissue engineering