Latest ArticlesGene therapy has obvious advantages in the treatment of ocular diseases due to the unique structure of the eye. In recent years, there are more and more therapeutic gene-based drugs for ophthalmic application in clinical trials. Most of the delivery vectors are adeno-associated virus and administered via intraocular injection, which has potential risks. Traditional remedies, such as topical instillationor systemic administration, have limited therapeutic effects on the diseases in the posterior segment of the eye, where the chemical drugs are hard to reach. This makes the research of new strategies for gene drug delivery extremely urgent. For better understanding of the latest hot topics of ocular gene therapy, this article is prepared to introduce application of gene therapy to the typical ocular diseases and the corresponding gene-based medicines. The absorption routes for gene delivery into eyes and existing barriers are summarized. Finally, the gene delivery strategies are highlighted. The clinical application of ocular gene therapy will be boosted by overcoming the absorbing barriers and reducing the potential pitfalls.
Apoptosis is an important self-stabilizing mechanism of multicellular organisms, which plays a vital role in the development of normal living organisms and the maintenance of tissue homeostasis. The abnormalities in apoptosis often lead to body lesions including tumors. Studies have shown that Bcl-2 protein with anti-apoptosis activity is an important target in the treatment of cancer. After nearly two decades of efforts, many small molecule Bcl-2 inhibitors have been discovered to induce cell apoptosis. The small-molecule Bcl-2 inhibitor, venetoclax, was developed based on fragment-based drug design strategy and approved by the FDA in 2016 for clinical application. This agent is the first approved small-molecule drug inhibiting Bcl-2 through protein-protein interaction to induce cell apoptosis. The achievement of venetoclax benefits from a combination of drug discovery technologies and represents a milestone in the history of drug discovery. In this review we will introduce the current progress in Bcl-2 inhibitors.
Chinese pharmacopoeia stipulates that the content of liquiritin in licorice slices should be no less than 0.5%. However, there are lots of unqualified licorice slices in the herbal medicine markets. Due to the important role of functional gene polymorphism in secondary metabolism, this study attempts to analyze the influence of chalcone synthase (CHS) gene polymorphism on liquiritin biosynthesis and find out the unique haplotypes in licorice samples with high or low content of liquiritin, and to provide a basis for further analysis of molecular mechanism in flavonoid biosynthetic pathway. The contents of the 4 main flavonoids (liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin) in 60 licorice samples were assayed by HPLC and the results were analyzed by Spearman and χ2 tests. The contents of the 4 main flavonoids were related to each other and obviously different in different original plants. They were highest in Glycyrrhiza uralensis samples and lowest in Glycyrriza inflate samples. Five G. uralensis samples with the highest liquiritin contents and five G. inflate samples with the lowest liquiritin contents were selected to clone the CHS cDNA sequences. 336 CHS cDNA sequences with a full length of 1 175 bp were obtained, 249 variable sites (141 missense mutation sites) were found, and 137 haplotypes were determined. 130 variable sites were found in the 336 CHS amino acid sequences and 102 types were determined. AA-3 is the major type of CHS in licorice, AA-35 is the special major type of CHS in the group with high flavonoids contents and AA-36 is the special major type of CHS in the group with low flavonoids contents. The mutation sites between AA-35 and AA-36 are I/V at 193 and V/T at 229. Discovery Studio 2.5 analysis of the three-dimensional structure of the CHS protein shows that the valine at site 229 of AA-35 is combined with malonyl-CoA. Homology analysis indicates that the homology of CHS among different species is low. This study is significant for identification of the unique haplotypes in licorices with high or low content of liquiritin and guiding the further molecular breeding of high-quantity licorice.
The flower bud of Tussilago farfara L. has been commonly used in the treatment of cough, bronchitis and asthmatic disorders in the Traditional Chinese Medicine. In Europe, the leaves were also used as herbal drugs with similar pharmacological activities. In order to utilize the leaves, it is important to conduct the chemical comparison between the flower buds and the leaves. In this study, ultra high liquid chromatography (UHPLC) coupled with Q Exactive high resolution mass spectrometry (HR-MS) was used to compare the chemical composition of the flower buds and leaves of T. farfara L. forty three metabolites were identified by the combination of targeted and untargeted approach. The results suggest that the sesquiterpenes, such as tussilagone and 7β-(3'-ethyl-cis-crotonoyloxy)-1α-(2'-methylbutyryloxy)-3(14)-dehydro-Z-notonipetranone were higher in the flower buds. While the phenylpropanoids, such as cholorgenic acid and isochlorogenic acid were higher in the leaves. The flavonoids, such as hyperin and quercetin exhibited no difference between the flower buds and leaves, while the rutin and kaempferol were higher in the flower buds. The leaves and flower buds had similar chemical components, and the phenylpropanoids, which were closely related with the antitussive and expectorant activities, were found at higher concentrations in the leaves. The results presented here laid the basis for the rational utilization of the leaves of T. farfara L.
The purpose of this study was to prepare T7 peptide modified vincristine loaded low density lipoprotein (T7-LDL-VCR) nanoparticles to penetrate through blood brain barrier for targeting the brain tumor cells.Firstly, the low density lipoprotein (LDL) nanoparticles were extracted and separated from human serum by density gradient centrifugation method, and then was loaded into the nanoparticle's lipid core by the dry film method, T7 peptide was covalent modified on the surface of the nanoparticles.T7-LDL-VCR was characterized by particle size, entrapment efficiency and peptide attachment efficiency.The fluorescent probe DiR was used to track the brain biodistribution of T7-LDL-VCR in mice bearing intracranial C6 glioma by means of in vivo imaging.The therapeutic effect of nanoparticles was observed with magnetic resonance imaging (MRI).Finally, relative tumor volume and survival curve were determined in mice.The results showed that the mean size of the prepared T7-LDL-VCR nanoparticle was about 30 nm, encapsulation efficiency was 30.1%, and peptide attachment efficiency was 63.88%.As expected, the prepared preparation has good brain targeting and good effect on the treatment of glioma in mice:the relative tumor volumes of T7-VCR-LDL, LDL-VCR and VCR were 30%, 51.50% and 79.25%, respectively; the median survival time (36 days), which was 2, 1.85 and 1.38 fold higher than that of physiological saline, free VCR and LDL-VCR, respectively.This study suggests that dual modified hposomes possessed a better ability penetrating the blood brain barrier to target the brain tumor with significant antitumor activities.
This study was aimed to explore the pharmacokinetics of epiberberine, jatrorrhizine, coptisine, palmatine, berberine of Jiaotai pill in the normal and depressed rats. According to 'Katz' method, the model of chronic unpredictable mild stress (CUMS) was established. The extract of Jiaotai pill was orally administered to rats, and the blood samples were collected via the the oculi chorioideae vein according to the time schedule. The concentrations of epiberberine, jatrorrhizine, coptisine, palmatine, berberine in rat plasma were determined by LC-MS/MS, and the pharmacokinetic parameters were calculated by DAS1.0 software. Compared with normal rats, the Cmax of palmatine, coptisine, berberine and jatrorrhizine in Jiaotai pill in depressed rats were 1.99, 2.14, 2.3, 1.82 times than the normal group, while the AUC0−t were 1.23, 1.25, 1.29, 1.46 times and the AUC0−∞ were 1.21, 1.25, 1.30, 1.43 times, which were significantly different.
Tonkinensis is commonly used in the treatment of hepatitis B infection in China with its effecttiveness in reducing clinical symptoms and improving liver function. However, the mechanism of the anti-HBV (hepatitis B virus) effect of Tonkinensis is still not clear. In this study, an integrative analysis using the network pharmacology and metabolomics was employed in identification of the main targets and mechanisms of Tonkinensis in treatment of HBV infections. First, the "drug-target" network was established by predicting the targets of the main chemical components of Tonkinensis; Secondly, the differential metabolites associated with the anti-HBV effect of Tonkinensis were analyzed with the LC-MS based metabolomics in HepG2.2.15 cells; Finally, the "drug ingredients-targets-metabolites" network was constructed to screen the main anti-HBV targets of Tonkinensis. The results suggest that Tonkinensis may act on 16 target proteins in the network of retinol metabolism, peroxisome proliferator activate-receptors (PPAR) signaling pathway and transcriptional regulation of cancer and so on, which contributed to the control of HBV replication and the regulation of immune function and metabolic disorders.
The difficulty to eradicate the HIV-1, off-target effects together with the rapid emergence of multidrug-resistant strains have created an urgent need for more potent and less toxic therapies against other targets of HIV virus. From the point of view of medicinal chemistry, we summarizes and discusses current endeavours towards the discovery and development of novel inhibitors with various scaffolds or distinct mechanisms of action, and also provides examples illustrating new methodologies in medicinal chemistry that contribute to the identification of novel antiretroviral agents.
Allene oxide cyclase (AOC), a key enzyme in biosynthesis of jasmonic acid, plays an essential role in the plant defense system.In present study, a full length cDNA of AsAOC gene was cloned by the reverse transcription PCR from Aquilaria sinensis calli.Meanwhile, the bioinformatics, prokaryotic expression, purification, tissue-specific expression analysis, and expression analysis under different abiotic stresses and hormone treatments were performed.The open reading frame (ORF) of AsAOC1 gene was 753 bp, encoding a protein of 251 amino acids with a calculated molecular mass (MW) of 27.46 kD.Bioinformatic analysis showed that AsAOC1 protein contains a conserved allene_ox_cyc domain in C-terminus.The phylogenetic analysis indicated that AsAOC1 protein had the highest level of homology with the AOC protein from Morus notabilis.The recombinant AsAOC1 protein was successfully expressed in Escherichia coli BL21(DE3) cells using the prokaryotic expression vector pET28a-AsAOC1 and was purified by Ni2+ affinity chromatography.Expression analysis in different tissues indicated that AsAOC1 was primarily observed in stems, and then stem tips and roots, following by leaves.The transcript level of AsAOC1 was induced by various abiotic stresses including salt, drought, cold, and heavy metal stress.Furthermore, AsAOC1 expression level was enhanced upon methyl jasmonate (MeJA), salicylic acid (SA), gibberellin (GA3), and abscisic acid (ABA) treatments.These results provide valuable insights into the role of JA in the mechanism of agarwood formation and plant defense system.
Immunotherapy is a new strategy for cancer treatment that has the potential to treat all types of cancer. T cell immunoglobulin and mucin-domain-containing molecule-3 (TIM-3) is a key negative regulator of T cell activation. TIM-3 blockage using anti-TIM-3 monoclonal antibody therapy has a great appeal and special advantages. Nanobodies, derived from heavy chain fragment in camelid animals, are now proving clinical values in the development of antibody drugs. In this study, we have immunized camel with TIM-3 antigens and then constructed phage display library. Moreover, 29 nanobodies with different complementarity-determining regions sequences have been screened from the phage display library by phage display technology. In addition, we successfully constructed the cell line stably expressing TIM-3, and screened 10 TIM-3 nanobodies with high specificity and high affinity using flow cytometry. Our study will lay the foundation for the future screening and development of anti-TIM-3 whole humanized functional nanobody.