Latest ArticlesPresent study investigated the role of mesenchyme homeobox 2 (MEOX2) gene in neurovascular dysfunction in Alzheimer's disease (AD) model rats by bilateral intracerebroventricular injection of Aβ1-42. One week after surgery, Morris water maze, immunohistochemistry, biochemical detection, Western blot and real-time PCR were used to detect the indexes. The animal studies were conducted in accordance with the Regulations of Experimental Animal Administration issued by the State Committee of Science and Technology of the People's Republic of China. Compared to the Sham-operated rats, Aβ1-42-operated rats showed obviously cognitive dysfunction, accompanied by increased Aβ, glial fibrillary acidic protein (GFAP), allograft inflammatory factor 1 (AIF1), endothelial nitric oxide synthase (eNOS) and decreased neuron specific enolase (NSE), synaptophysin (SYN), CD34, vascular endothelial growth factor (VEGF) expressions of brain. Aβ1-42-operated rats also increased the endothelin (ET) level and decreased nitric oxide (NO) level in brain tissue. Moreover, MEOX2 expression was decreased correlated with low density lipoprotein receptor-related protein 1 (LRP-1) decreasing and receptor for advanced glycation end products (RAGE) increasing in brain tissues of AD model rats. We found the correlation between MEOX2 gene expression and neurovascular dysfunction, in addition, the decreased MEOX2 may involve in increasing the accumulation of Aβ in brain by relating to the decreased LRP-1 and increased RAGE which is located in blood-brain barrier (BBB) in senescence-accelerated mice.
To investigate the anti-inflammatory mechanisms of taurochenodeoxycholic acid (TCDCA), the molecule structure file of TCDCA was downloaded from PubChem database, PharmMapper and GeneCards were used to predict and screen the targets of TCDCA. STRING database and Cytoscape software were used to construct protein interactions network. GO and KEGG analysis was preformed through STRING database. The key targets were validated by molecular docking and the targets type was attributed by DisGeNET database. The network showed that 89 targets were involved in 68 biological processes including response to stimulus, multicellular organismal process, single-multicellular organism process, response to chemical, response to organic substance, by adjusting 51 signaling pathways, such as pathways in cancer, progesterone-mediated oocyte maturation, MAPK signaling pathway, proteoglycans in cancer. These findings provide an overview of anti-inflammation of TCDCA, which reflects the characteristic of multi-targets and multi-pathways of TCDCA. It pointed out the direction for further research on anti-inflammatory mechanism of TCDCA.
The computer-aided design was used to simulate the docking of PDGF receptor with known active compounds, and the active groups that can bind to key sites were identified by analyzing the key amino acid residue fragments that exerted active effects on the target proteins. The natural product oleanolic acid was used as the parent, and the active group was introduced into the 2-position, and the C-28 carboxyl group was esterified and amidated. A series of oleanolic acid analogues targeting PDGF receptor inhibitors were designed and synthesized. Their structures were confirmed by MS and NMR. Through MTT assay, SGC-7901 and A549 cells were selected for preliminary in vitro anti-tumor activity screening. PDGF receptor protein inhibition test was performed on Ⅰ3 and Ⅱ5 by FPIA. The activity tests showed that Ⅰ3 and Ⅱ5, compared with the positive control drug, had stronger inhibition. FPIA test showed that Ⅱ5 and PDGF receptor protein had good binding ability. The newly synthesized oleanolic acid analogues have significantly higher antitumor activity than the parent compound and deserve further study.
Curcumin, a polyphenolic compound from the plant Curcuma longa L., has shown a wide-spectrum of anti-inflammatory and antitumor activities. Despite the promising biological effects of curcumin, its poor solubility has restricted its use in the management of human ailments. To improve its water-solubility, curcumin succinate prodrugs were designed and synthesized and their aqueous solubility, stability, metabolism in rats and anti-inflammatory activity were evaluated (experiments had been approved by the ethics committee and carried out in accordance with the relevant guidelines and regulations; rats were provided by Beijing courtyard experimental animal center of Academy of Military Medical Sciences). The results showed that curcumin succinate prodrugs are very soluble in water and more stable than curcumin in water and in phosphate buffer solution. They released curcumin rapidly and quantitatively after intravenous administration. In phlogogen-induced paw edema in rats, curcumin succinate prodrugs showed anti-inflammatory activity as potent as dexamethasone.
For qualitative and quantitative analysis of related substances in clotrimazole cream, HPLC-Q-TOF spectrometer was used to analyze the fragmentation pathways and identify structures of the related substances. Five related substances named by BP (2018) were identified as impurity A ((2-chlorophenyl)-diphenylmethanol), impurity B (para-clotrimazole isomer), impurity E (2-chlorobenzophenone), impurity F (1-tritylimidazole) and impurity 4 (9-(2-chlorophenyl)-fluorene), respectively, by using impurity references matching and comparison with the literature data. Four related substances were detected in clotrimazole cream except impurity E, and 9-(2-chlorophenyl)-fluorene is the first identified impurity in this preparation. To establish an HPLC method for determination of the related substances in Clotrimazole Cream, the Agilent Poroshell Bonuns RP column was used (100 mm×4.6 mm, 2.7 μm) with UV detection at 215 nm. The mobile phase was acetonitrile-10 mmol·L-1 dipotassium phosphate buffer (adjusted with phosphoric acid to pH of 5.80) with a flow rate of 1.0 mL·min-1. Gradient elution was used. The column temperature was maintained at 40℃. A good linear behavior was achieved between component's concentrations and peak area for impurity A, B, E, F within the range of 0.20-10.02 μg·mL-1, 0.20-10.00 μg·mL-1, 0.20-10.10 μg·mL-1, 0.10-5.01 μg·mL-1 with the correlation coefficients were 0.999 7, 1.000 0, 1.000 0, 0.999 9, respectively. The average recoveries were 94.3%, 95.0%, 100.0%, 99.6% with RSDs were 2.8%, 2.2%, 1.1%, 2.7%, respectively (n=9). LOQ were 200.4, 200.0, 202.0, 100.2 ng·mL-1, respectively. LOD were 57.25, 57.14, 57.71, 28.63 ng·mL-1, respectively. The developed method was simple, rapid, accurate and effective for testing related substances in clotrimazole cream to control its quality, ensuring the safety of clinical medication.
A non-reduced SDS-PAGE purity method for quantitation of conbercept fragments was established based on gel screening, comparison of gel imaging system, linearity range of main band, screening of destaining conditions. The results indicated that the bands could be separated effectively with good clearness and flatness on 4%-15% gradient concentration gel, the peaks of all bands could be separated from baseline using high-distinguishability gel imaging system, the signal intensity of a main band had shown a good linearity with ≤ 3 μg of loading amount, and that the destaining was set as a total of ≤ 3 h with exchanging 100 mL destaining buffer every 60 min. The established non-reduced SDS-PAGE method could demonstrate the purity of conbercept more objectively. After validation, the established non-reduced SDS-PAGE method was submitted to FDA in the form of supplementary materials, which laid a quality basis for the direct entry of conbercept to the clinical Ⅲ study in the United States.
In this study a reduction-responsive nanoparticles (NPs) modified with hyaluronic acid (HA) was prepared for the co-delivery of doxorubicin (DOX) and siRNA and then evaluated as a lung cancer targeting delivery system in vitro. The amphiphilic polymer of poly-L-lysine-lipoic acid (PLA) based on poly-L-lysine (PLL) with lipoic acid (LA) was synthesized via amidation reaction and characterized by 1H NMR. The DOX loaded PLA NPs were prepared via dialysis method, and siRNA was loaded via electrostatic attraction to prepare the co-delivery NPs system (PLA/DOX-siRNA-NPs). Then PLA/DOX-siRNA-NPs were coated with HA to obtain HA-PLA/DOX-siRNA-NPs. The tumor microenvironment-responsive properties under different pH or reduction condition of HA-PLA/DOX-siRNA-NPs were evaluated by investigating the particle size and zeta potential. Cellular uptake of HA-PLA/DOX-siRNAFAM-NPs by A549 cells and endosomal escape of siRNA were studied using confocal laser scanning microscope (CLSM). 1H NMR spectrum demonstrated that PLA was successfully synthesized with LA grafting rate of 25.1%. The encapsulation efficiency (EE) and drug loading (DL) of HA-PLA/DOX-NPs was (86.93±8.91)% and (4.17±0.68)%, respectively, and siRNA was loaded at an N/P of 6:1 in carrier. HA-PLA/DOX-siRNA-NPs exhibited a suitable size of (167.3±9.9) nm and negative charge of (-15.5±1.4) mV with the optimal ratio of PLA and HA of 1:3. Additionally, the zeta potential of HA-PLA/DOX-siRNA-NPs significantly increased with charge reversal from negative to positive after the treatment with HAase, and the particle size of HA-PLA/DOX-siRNA-NPs changed significantly under the condition of 10 mmol·L-1 glutathione (GSH). The release profiles in vitro demonstrated that HA-PLA/DOX-NPs exhibited a maintained release behavior at pH 7.4 and the adding of GSH (10 mmol·L-1) led to rapid release of DOX from NPs. In vitro cellular uptake and subcellular distribution study demonstrated that themodification of HA enhanced the affinity of NPs to A549 cells and targeting ability, and the cellular uptake of HA-PLA/DOX-siRNAFAM-NPs significantly increased after the treatment with HAase. It was observed that HA-PLA/DOX-siRNAFAM-NPs could escape from endo-lysosomes followed by sharp payloads release to their relative targets. All these results demonstrated that the co-loaded NPs have a high entrapment efficiency of DOX and siRNA. And they also exhibited an active tumor targeting efficiency and tumor microenvironment-responsive properties, which were beneficial to cellular uptake and intracellular release of DOX and siRNA. In conclusion, these reduction-responsive NPs modified with HA have great potential as co-delivery systems for antitumor agents and siRNA.
Annonaceous acetogenins (ACGs) are effective part extracted and separated from Annona squamosa seeds, they have good antitumor activity against a variety of tumor cells. However, the solubility of ACGs is poor with serious toxic and side effects, which greatly limits their application in clinical practice. In this study poloxamer 188 (P188) was selected as a drug carrier or a stabilizer to prepare ACGs nanosuspensions (ACGs-NSps) using anti-solvent precipitation. The nanosuspensions were examined via dynamic light scattering (DLS) method to examine size of the nanosuspensions. Transmission electron microscopy was used to observe their morphology. HPLC assay was used to measure their drug loading content and the in vitro drug release. The stability of ACGs-NSps at room temperature, in various physiological media and plasma, and the hemolytic test and lyophilization were all investigated. MTT assay was performed to study the cytotoxocity of ACGs-NSps against four tumor cell lines. 4T1 bearing tumor model was used to assess their in vivo antitumor therapeutic efficacy. The obtained ACGs-NSps were spherical, the average particle size was 169.4±1.25 nm, the polydispersity index (PDI) value was 0.130±0.020, the zeta potential was -19.8 mV and the drug loading content was 48.18%. ACGs-NSps were stable at room temperature for at least 15 days. They could be lyophilized in the presence of 0.5% glucose and 2.0% P188. ACGs-NSps showed sustained in vitro drug release, and the cumulative drug release reached 80.82% within 144 hours. ACGs-NSps maintained their particle size in various physiological media, and plasma with no hemolysis and then met demands of both oral and intravenous administration. In contrast to free ACGs, ACGs-NSps displayed significantly higher cytotoxicity against 4T1 (IC50, 0.892±0.124 μg·mL-1 vs 2.495±0.108 μg·mL-1, P < 0.05), HeLa (IC50, 0.747±0.051 μg·mL-1 vs 2.204±0.064 μg·mL-1, P < 0.01), HepG2 (IC50, 2.265±0.081 μg·mL-1 vs 4.159±0.071 μg·mL-1, P < 0.01), and MCF-7 (IC50, 0.473±0.024 μg·mL-1 vs 1.196±0.022 μg·mL-1, P < 0.05). The in vivo study demonstrated that the daily oral administration of ACGs-NSps (3 mg·kg-1) resulted in higher tumor inhibition rate compared to ACGs/oil solution (67.23% vs 53.11%), comparable to the intravenous injection of 0.5 mg·kg-1 ACGs-NSps every other day (70.34%). Nanosuspensions effectively solved the problem of ACGs insolubility and difficulty in drug delivery. Using P188, a pharmaceutic adjuvant approved by FDA for iv injection, the resultant ACGs-NSps appear promising as an anti-tumor drug that can be used in clinic.
The development and metabolism of medicinal plant is affected by many factors, among which the effect from endophytic fungi has been noticed recently and has become one of hot fields. In order to explore the effect of endophytic fungi on gene expression in R. crenulata, RNA-sequencing was used to find genes involved in metabolic pathways, and the differential genes were verified by real-time fluorescent quantitative PCR. The method of 2-△△Ct was used to analyze the relative expression levels of genes in related metabolic pathways, which was used to verify the result of transcriptomics sequencing. The results showed that the endophytic fungus, P. fortinii, could up-regulate the gene expression in lipid metabolic pathway of R. crenulata. In signal transduction pathway, the genes were influenced at different level but the gene expressions were significantly increased under control of Notch signaling pathway, which was 34 times of that in control. The gene expressions of environmental adaption pathway were up-regulated in R. crenulata after inoculation of P. fortinii. This study could provide help for further understanding on mechanism of plant-fungus interaction, root cause of geoherbalism of medicinal plant and exploring bio-function of endophytic fungi.
Macrophage migration inhibitory factor (MIF) is a classical pro-inflammatory cytokine that plays an important role in the innate and adaptive immune regulation. In recent years, a large number of studies have demonstrated that the expression level of MIF is significantly increased in a variety of tumor tissues and MIF promotes the occurrence and development of tumors. MIF participates in the regulation of tumor growth, metastasis, angiogenesis, as well as induces and maintains the tumor microenvironment. Targeting MIF has been considered as a candidate strategy against cancer. In this review, the structural features, the signaling pathway, the biological functions of MIF are briefly outlined. Moreover, approaches that target MIF in the treatment of cancer are also summarized.