Latest ArticlesPuerarin(PUE), as an isoflavone component, has a wide range of pharmacological activities, while its poorly aqueous solubility limits the development of solid oral dosage forms. In this study, PUE along with nicotinamide(NIC) were prepared into the coamorphous system by solvent-evaporation method and characterized by powder X-ray diffraction(PXRD), differential scanning calorimetry(DSC) and Fourier transform infrared spectroscopy(FT-IR). In addition, its dissolution behavior and solubilization mechanism were also investigated.PUE-NIC coamorphous was a single homogeneous binary system, with a single glass transition temperature at 35.1 ℃. In comparison to crystalline PUE, during the dissolution process, coamorphous PUE-NIC not only exhibited the "liquid-liquid phase separation"(LLPS) phenomenon, but the formation of Ap type complexation(1∶1 and 1∶2)between PUE and NIC molecules was also verified, which significantly improved the solubility of PUE and prolonged the supersaturation time, and would benefit its absorption.
The therapeutic effect of tumor photodynamic therapy is severely limited by the hypoxic tumor microenvironment. Inhibiting tumor celloxygen consumption is a more effective way than increasing its oxygen supply to overcome the tumor hypoxia and enhance photodynamic therapy. To carry out this strategy, the supramolecular nanoparticles VER-ATO-SMN loaded with photosensitizer verteporfin(VER), oxygen-consuming inhibitor atovaquone(ATO), and stabilizer polyvinylpyrrolidone(PVP)-K30 were prepared by the nanoprecipitation method, and the optimal prescription was screened and optimized by single factor experiments. The results showed that the optimal prescription for VER-ATO-SMN was ATO∶VER(w/w) = 1∶1, PVP-K30 = 100 mg, N, N-dimethylformamide∶water(v/v) = 1∶10. The morphology, particle size, particle dispersion index and encapsulation efficiency of supramolecular nanoparticles were characterized. The VER-ATO-SMN showed a spherical morphology and was well dispersed. The hydrodynamic size of VER-ATO-SMN was 101.21 ± 4.30 nm as determined by dynamic light scattering(DLS). The encapsulation efficiencies of VER and ATO in VER-ATO-SMN prepared with the optimal prescription were 70.86% and 77.52%, respectively. The VER-ATO-SMN exhibited good laser stability and also showed high stability in conditions which simulated the physiological solution. Compared with free VER and VER liposome, VER-ATO-SMN performed enhanced therapeutic effect at the cell level. The mechanism was that VERATO-SMN could effectively incorporate into cells and improving the intracellular oxygen concentration by reducing the oxygen consumption of tumor cells could increase the amount of reactive oxygen species generated by VER mediated photodynamic therapy. The in vivo anticancer efficacy results of tumor-bearing mice suggested that VER-ATO-SMN could effectively inhibit the tumor growth or even completely eliminate the tumor. All animal experiments were performed in line with national regulations and approved by the Animal Experiments Ethical Committee of 900 Hospital of the Joint Logistics Team.
After entering the physiological environment, proteins and other biomolecules bind to the nanoparticles' surface, called protein corona. The corona establishes a new bio-interface that affects its physicochemical properties and biological behaviors. Variations in types and contents of human plasma proteins during the different physiological states can substantially change the composition and effects of the corona. With folic acid(FA)-modified polylactic acid-polyglycolic acid copolymer(PLGA) nanoparticles, the formation of protein coronas and their influence on the targeting capability are studied in healthy and ovarian human plasma. All human plasma samples were collected at the Peking University Third Hospital and this study protocol has been approved by Peking University Third Hospital Medical Science Research Ethics Committee(2019-409-1). Dynamic light scattering measurements demonstrated a 10-40 nm increase in their size distributions and a 30 mV decreased in their absolute zeta-potential since protein corona-coated PLGA-PEG and PLGA-FA were formed. The SDS-PAGE analysis showed the composition of the protein coronas from ovarian and healthy plasma in PLGA-FA were markedly distinct, particularly for proteins with molecular weight of 45, 110 and > 180 kDa. Flow cytometry indicated that the absorption of ovarian plasma in PLGA-FA led to a lower cellular uptake by SKOV3 cells. Our results suggest that in vitro formed ovarian plasma protein corona could shield targeting molecules and reduced receptor-mediated internalization. The results of this pilot study will provide evidence of the effectiveness of active targeting nanoparticles under pathologic conditions. Additionally, the protein corona in different diseases is emerging as a key point; thus, a comprehensive understanding could accelerate clinical translation of functionalized nanoparticles.
As a key gene in the regulation of long-chain fatty acid biosynthesis, 3-ketoacyl-CoA synthase (KCS) plays an important role in the growth and development of Coix lacryma-jobi L. In this study, the KCS gene was cloned from cDNA of Coix lachryma-Jobi L. and bioinformatics analysis was performed. Results showed that the full length KCS gene was 1 548 bp encoding 515 amino acids. Bioinformatics analysis indicated that the gene encoded a 58 608.12 Da protein with an isoelectric point of 9.20 containing two transmembrane helical structure domains and lacking a signal peptide, with a likely subcellular localization in main plastid membranes. The results of multiple sequence comparisons and evolutionary tree analysis revealed that KCS had three identical conserved sequences and was closely related to KCS from monocotyledons such as Sorghum bicolor, Zea mays, Setaria italica, Panicum miliaceum, Oryza brachyantha, Hordeum vulgare, Aegilops tauschii subsp. Tauschii. We speculated that the evolution of the gene was similar among these plants of the same family. In addition, gene expression analysis showed that the KCS gene was significantly different in Coix lacryma-jobi L. isolates having different lipid content. This work will facilitate further study of the regulatory mechanism of this enzyme in fatty acid synthesis.
Bupleurum L.(Apiaceae) is an economically important genus, in which many species are of medicinal value. In this study, the complete plastid genomes(plastomes) of B. chinense DC. and B. boissieuanum H. Wolff were sequenced and their characteristics were investigated. Comparative and phylogenetic analyses were conducted with other published Bupleurum plastomes. The complete plastomes of B. chinense and B. boissieuanum were 155 458 and 155 800 bp in length, and both exhibited the typical quadripartite circular structure consisting of a large single copy region(LSC, 85 343 and 85 804 bp), a small single copy region(SSC, 17 495 and 17 410 bp), and a pair of inverted repeat regions(IRa/b, 26 310 and 26 293 bp), respectively. A total of 129 genes, including84 protein-coding genes, 37 transfer RNA(tRNA) genes, and eight ribosomal RNA(rRNA) genes were identified from each of the two plastomes. Repeat sequences detected were similar in types and distribution patterns, but the numbers were slightly different. Comparative analyses revealed that the Bupleurum plastomes were highly conserved in length, structure, the guanine and cytosine(GC) content, and gene content and order, both intraspecifically and interspecifically, and no obvious expansion or contraction of the inverted repeat regions occurred. Sequence variation was lower within the same species than among different species, noncoding sequences(including intergenic regions and introns) showed a higher divergence than the protein-coding sequences, and sequences in the LSC and SSC regions were more divergent than those in the IR regions. In addition, 11 sequences with higher nucleotide diversity among species were detected in the LSC and SSC regions. All studied Bupleurum species were inferred forming a monophyletic group with a 100% bootstrap value. Bupleurum chinense and B. boissieuanum were phylogenetically closest to B. commelynoideum and B. falcatum, separately, with all three B. chinense accessions clustered into a distinct clade. These results provide genetic information for further species identification, phylogenetic resolution, and will assist in exploration and utilization of medicinal Bupleurum species.
Chalcone isomerases (CHIs) play an essential role in the biosynthesis of flavonoids important in plant self-defense. Based on the transcriptome data of Aquilaria sinensis Calli, a full-length cDNA sequence of CHI1 (termed as AsCHI1) was cloned by reverse transcription PCR. AsCHI1 contains a complete open frame (ORF) of 654 bp. The deduced protein is composed of 217 amino acids, with a predicted molecular weight of 23.11 kDa. The sequence alignment and phylogenetic analysis revealed that AsCHI1 has conserved most of the active site residues in type I CHIs, indicating a close relationship with the CHI from Gossypium hirsutum. The recombinant AsCHI1 protein was obtained by heterologous expression of AsCHI1 in E. coli BL21(DE3). The purified AsCHI1 protein exhibited CHI activity by catalyzing the production of naringenin from naringenin chalcone. Remarkably, AsCHI1 expression in A. sinensis Calli treated with various abiotic stresses including salt, mannitol, cold, and heavy metals could be markedly increased, and plant hormones such as abscisic acid (ABA), gibberellin (GA3), and salicylic acid (SA) could also increase the expression of AsCHI1, suggesting that AsCHI1 might play an important role in plant self-defense. The results expand our understanding of the biosynthesis of flavonoids in A. sinensis and give further insight into the defensive responses of A. sinensis to abiotic and biotic stresses.
The α4β2-nicotinic acetylcholine receptor(nAChR) is a ligand-gated ion channel that is distributed throughout the nervous system. It is involved in the regulation of various neurotransmitters including acetylcholine, dopamine, γ-aminobutyric acid, and norepinephrine. α4β2-nAChR plays an important role in learning, memory, cognition, attention, inflammation, and pain. A large number of studies have shown that α4β2-nAChR is an important therapeutic target for neurological diseases such as Alzheimer's disease, Parkinson's disease, epilepsy, depression, nicotine dependence, pain, etc. It is an important target in the early diagnosis and curative effect detection of neurodegenerative diseases including Alzheimer's disease. This review summarizes the role, mechanisms and related drug research advances on α4β2-nAChR ligand drugs in neurological diseases, as well as providing a theoretical basis for identifying and developing more suitable α4β2-nAChR-related compounds.
Fibrosis is a pathological process of abnormal hyperplasia and excessive deposition of extracellular matrix during the process of repair after tissue and organ damage. Injury/inflammation caused by variously chronic diseases is a major trigger for fibrogenesis. Fibrosis of the liver and kidney is a common organ fibrosis. Recently, the intestinal microbiota has been shown to be extensively involved in the development of liver and kidney diseases, which may follow from changes in the intestinal microbial composition and intestinal integrity. This promotes the development of liver and/or kidney fibrosis through endocrine, cell signaling and other pathways. This paper reviews the research progress in understanding liver fibrosis and kidney fibrosis based on the gut-liver-kidney axis, which may be helpful for providing new strategies and theoretical basis for the diagnosis and treatment of hepatic and renal fibrosis.
Prostate cancer is one of the common malignant tumors of male urogenital system, and the incidence of prostate cancer in China has increased significantly in the past decade. At present, endocrine therapy based on androgen blockade is the main method of clinical treatment except radical surgery and radiotherapy/chemotherapy for prostate cancer. However, the clinical benefit can only be obtained in the early stage of treatment, and nearly90% of patients will develop to the castration resistance, and among them, nearly 90% of patients will have bone metastasis. The quality of life decreases sharply with the progression of disease for patients. In addition to the androgen signal pathway, studies have shown that many other oncogenic signal pathways have involved in the development of castration resistance, including classic cancer signaling pathways, immune and inflammatory signaling pathways, etc. Understanding the mechanism of androgen independent signal pathway in the formation of castration resistance will help to understand the off-target effect of androgen blocking therapy and introduce new treatment targets or strategies to get rid of the "no drug available" dilemma for clinical treatment of castration resistance.
Depression is a serious mental illness with a high incidence. At present, we do not fully understand the specific pathological mechanisms of depression, and the efficacy of drug treatments is very limited. Recent studies have shown that epigenetic changes that occur in specific brain regions may be a key mechanism by which environmental factors to interact with individuals to influence the risk of depression. Therefore, drugs that target epigenetic regulation may become a new direction for the development of antidepressants. Histone deacetylase inhibitors (HDACi) are a class of compounds that inhibit histone deacetylase activity, which has been reported to be associated with depression; this article addresses the use of HDACi in preclinical studies, and their potential therapeutic role and limitations of use in depression.