ArchiveIn 2018, FDA approved 59 kinds of new drugs in all, breaking the record of 53 set in 1993. There were 34 types of small molecule drugs, which accounted for 64% of the whole new drugs. Of these 34 new small molecule drugs, 9 first-in-class ones marked a milestone for the subsequent drug discovery and development. These include Glasdegib, the world's first small molecule inhibitor targeting Smo through Hedgehog signaling pathway; Ivosidenib, the first small molecule inhibitor targeting mutant IDH1; Tecovirimat, the first small molecule drug for anti-variola virus therapy through targeting p37; Baloxavir marboxil, the first anti-flu drug targeting cap-dependent endonuclease; Elagolix sodium, the first small molecule inhibitor in treating endometriosis by targeting GnRH-R, etc. The research and development of first-in-class drugs is always full of obstacles and challenges. However, once they were successfully recognized as the "heavy bomb" drugs, they would become huge benefits. This article chose the representative first-in-class small molecule drugs that were approved in 2018 as examples to analyze their development processes in an attempt to provide guidance for the research and development of more first-in-class drugs.
In rodents, bilateral olfactory bulbectomy (OBX) results in a series of changes in behaviors and neurobiology, similar to the clinical symptoms of depression in patients. These changes can be reversed by chronic but not acute treatment of antidepressants. Owing to the face, construct and predictive validities, the OBX model has been used to investigate the mechanisms of depression, screen for antidepressants, and reveal the mechanism of drug action. In addition, there are certain features in OBX animals resembling those of patients with Alzheimer's disease (AD), including the impaired learning and memory ability and the accumulation of amyloid-β protein (Aβ). In this review, we present the association between olfaction and depression or AD, the surgical procedure of OBX, the behavioral features of OBX animals, the abnormal changes in cortex and hippocampus, and the application of this model for studying depression and AD. These lines of information are important for the development of antidepressant and anti-dementia drugs using this model.
As the primary innate immune cells in the central nervous system, microglia can be activated by external noxious stimulus and in turn interact with astroglia and neurons to induce neuroinflammation and facilitate the transmission of pain signals. This response can help the central nervous system adapt to the changes of the internal environment induced by noxious stimulus, leading to the long-term sensitivity of peripheral and central pain nerve conduction pathways and chronic neuropathic pain. Numerous researches found that activation of microglia participated in the occurrence and maintenance of chronic neuropathic pain, and inhibition of microglial activation in the spinal cord or the brain had analgesic effect in animal experiments. Due to the fact that molecular and cellular mechanisms between the activation of microglia and pain remittence are unclear, there are many difficulties in designing of new drugs selectively targeting to the activation of microglia for treatment of chronic neuropathic pain. We review here the research articles on microglia and chronic neuropathic pain, sorting out the relationship between microglia and chronic neuropathic pain, and provide new ideas for the development of new drugs targeting to microglia for the treatment of chronic neuropathic pain.
Elabelas/Toddlers belong to a group of endogenous active peptides recently discovered from zebrafish. The sequences of these peptides have 25% homology to Apelin. These peptides regulate physiological functions of organisms through putative protein receptors related to the angiotensin receptor AT1 (APJ). Functional roles of Elabela include early embryonic development, angiogenesis, fluid homeostasis, and feeding or dietary behavior control. Elabela also participates in the development of many diseases, such as heart failure, preeclampsia, acute kidney injury, hypertension, and diabetes. Increasingly, studies have shown that Elabela/APJ signaling can promote normal development of early embryos, including differentiation of mesoderm and endoderm, and formation of cardiac morphology and function. At the same time, the signaling can also promote angiogenesis or migration and proliferation of tumor cells. Here we describe the molecular structure, biological characteristics, functions and application prospects of Elabela/APJ signaling.
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), as a label-free imaging technique with high coverage and sensitivity is widely used for visualizing the spatial distribution of proteins, peptides and small metabolites in tissues. With the development of MALDI technique, MALDI-MSI is also employed to monitor the spatial distribution of phytochemical constituents of medicinal plants. In this review, we first briefly introduce MALDI-MSI technique, and we focus on its application in the spatial distribution and accumulation of secondary metabolites in medicinal plants. The ultimate advantage of using MALDI-MSI for spatial distribution analysis at the molecular level, offers crucial evidence of synthesis, transfer and accumulation of bioactive molecules in medicinal plants.
Flavonoids are important active ingredients in traditional Chinese medicine. However, their applications for the pharmaceutical use are greatly limited by low oral bioavailability due to poor aqueous solubility. The study of pharmaceutical crystallography is a potential approach to solve many problems of poor solubility. Research progress of flavonoid compounds in pharmaceutical crystallography field was reviewed from following aspects:polymorphism, cocrystal, amorphous/co-amorphous and nanocrystals. The information provided here is expected to serve as a reference for the applications of pharmaceutical crystallography in the poorly soluble components of traditional Chinese medicine.
This study aims to investigate the effect of down-regulation of miR-205-5p by transfection of miR-205-5p inhibitor on the sensitivity of HNE1/DDP cells to cisplatin (DDP) induced apoptosis and explore the underlying mechanism. qRT-PCR was used to detect the expression of miR-205-5p in HNE1 or HNE1/DDP cells. The expression level of miR-205-5p was analyzed after transfecting HNE1/DDP cells with miR-205-5p inhibitor. MTT assay was used to evaluate the inhibitory effect of DDP alone or in combination with miR-205-5p inhibitor on the proliferation of HNE1/DDP or HNE1 cells. Apoptosis of cells treated with miR-205-5p inhibitor alone or in combination with DDP (8 μmol·L-1) was assessed using flow cytometry with PI staining, with the nucleus was counterstained with DAPI staining. The expression of Bax, Bak, Mcl-1, or Bcl-2 was analyzed by Western blot. HNE1/DDP cells showed a high level of expression of miR-205-5p, and the expression of miR-205-5p was significantly decreased by transfection of miR-205-5p inhibitor. Down-regulation of miR-205-5p significantly increased the sensitivity of HNE1/DDP cells to DDP (P < 0.05). Transfection of miR-205-5p inhibitor enhanced the sensitivity of HNE1/DDP cells to DDP induced apoptosis. Treatment of HNE1/DDP cells with miR-205-5p inhibitor combined with DDP (8 μmol·L-1) for 24 h resulted in an apoptotic rate of 28.93% ±2.50%, significantly higher than that treated with miR-205-5p inhibitor (9.83% ±1.31%) or DDP alone (10.83% ±1.70%) (P < 0.05). DAPI staining showed that HNE1/DDP cell nucleus became significantly condensed and fragmented in miR-205-5p inhibitor combined with DDP group. The combined group up-regulated the expression of Bax and down-regulated the expression of Bcl-2 in HNE1/DDP cells. Therefore, down-regulation of miR-205-5p can enhance the sensitivity of HNE1/DDP cells to cisplatin induced apoptosis, and the mechanism may involve up-regulation of Bax and down-regulation of Bcl-2 expression.
To explore the effect of total extract of Chrysanthemum morifolium on lipopolysaccharide (LPS)-induced acute lung injury in mice, we studied the effects of three caffeoyl quinic acids isolated from Chrysanthemum morifolium on vascular endothelial cell injury and their mechanisms of action. All animal experiments were carried out strictly in accordance with the National Animal Welfare Ethics and Protection Regulations. A mouse model of acute lung injury was established by intranasal instillation of LPS. After 6 days of oral administration of chrysanthemum extract, the lung wet weight/dry weight ratio, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured in mouse bronchoalveolar lavage fluid. Human umbilical vein endothelial cells (HUVEC) were serum starved for 12 h and treated with 2.5 μg·mL-1 LPS for 24 h to establish the in vitro model of vascular endothelial cell injury. After 24 h of treatment of caffeoyl quinic acids from Chrysanthemum morifolium, the levels of TNF-α, IL-6, IL-1β, vascular cell adhesion molecule-1 (VCAM-1) and endothelin-1 (ET-1) were measured by ELISA in the cell culture supernatant, the malondialdehyde (MDA) level was detected by TBA method, the superoxide dismutase (SOD) level was determined by hydroxylamine method, and the nitric oxide (NO) level was assayed by a one-step method. The levels of p-MEK1/2, MEK1/2, p-ERK1/2, ERK1/2, p-JNK, JNK, p-P38 and P38 of mitogen-activated protein kinase (MAPK) signaling pathway were detected by Western blot. The total extract of Chrysanthemum morifolium can significantly reduce the wet weight/dry weight ratio of lung in mice and the levels of TNF-α, IL-6 and IL-1β in alveolar lavage fluid. The caffeoyl quinic acids from Chrysanthemum morifolium significantly increased the levels of SOD and NO, decreased the levels of TNF-α, IL-6, IL-1β, VCAM-1, ET-1 and MDA, and significantly reduced the levels of p-MEK1/2, p-ERK1/2. In conclusion, total extracts of Chrysanthemum morifolium exhibit certain protective effect on mice with acute lung injury, and three caffeoyl quinic acids from Chrysanthemum morifolium may improve LPS-induced vascular endothelial cell injury by inhibiting inflammatory cytokines and oxidative stress, and regulating inter-cellular adhesion molecule and vasomotor factors through ERK/MAPK signaling pathway.
Alzheimer's disease (AD) is a neurodegenerative disease that seriously threatens the life of the elderly and there is no effective therapy to treat or delay the onset of this disease. Due to the multifactorial etiology of this disease, the multi-target-directed ligand (MTDL) approach is an innovative and promising method in search for new drugs against AD. In order to find potential multi-target anti-AD drugs through reposition of current drugs, the database of global drugs on market were mined by an anti-AD multi-target prediction platform established in our laboratory. As a result, inositol nicotinate, cyproheptadine, curcumin, rosiglitazone, demecarium, oxybenzone, agomelatine, codeine, imipramine, dyclonine, melatonin, perospirone, and bufexamac were predicted to act on at least one anti-AD drug target yet act against AD through various mechanisms. The compound-target network was built using the Cytoscape. The prediction was validated by molecular docking between agomelatine and its multiple targets, including ADORA2A, ACHE, BACE1, PTGS2, MAOB, SIGMAR1 and ESR1. Agomelatine was shown to be able to act on all the targets above. In conclusion, the potential drugs for anti-AD therapy in the database for global drugs on market was partially uncovered using machine learning, network pharmacology, and molecular docking methods. This study provides important information for drug reposition in anti-AD therapy.
Sangzhi alkaloids (SZ-A) are derived from traditional Chinese medicine Ramulus Mori, serving well as an innovative antidiabetic drug, due to α-glucosidase inhibition. To evaluate the potency of glucosidase inhibitory effect of SZ-A, the enzyme-based screening platforms, including sucrase, maltase and amylase were established, and IC50 was calculated. The effects of SZ-A on postprandial blood glucose at a single dose, oral sucrose, starch and glucose loading were determined in normal ICR mice and alloxan-induced hyperglycemic mice. To confirm the anti-diabetic effects of SZ-A on glucose and lipid metabolism after long-term administration, the postprandial and fasting blood glucose, serum insulin, urinary glucose levels, glycosylated serum proteins and blood lipid levels were determined in high-fat fed C57 obese mice (pre-diabetic HFC57 mice) and diabetic rats induced by streptozotocin (STZ). The Experimental Animal Welfare Ethics Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College approved all of the protocols for this research. We found that SZ-A exhibited a significant inhibitory effect on the sucrase and maltase. SZ-A showed no effect on amylase. In normal ICR mice and alloxan-induced hyperglycemic mice, SZ-A at a single dose significantly delayed and reduced the peak of blood glucose after sucrose or starch loading, but showed no effect on the increase of blood glucose after glucose loading. In STZ diabetic rats, SZ-A significantly reduced the postprandial or fasting blood glucose levels, glycosylated serum proteins and urinary glucose. SZ-A also reduced serum triglyceride (TG) and cholesterol (TC) levels after 3 weeks of treatment. SZ-A ameliorated the postprandial blood glucose or the fasting blood glucose elevation, and reduced the incidence of hyperglycemia in HFC57 mice. SZ-A decreased the basal insulin level, improved insulin sensitivity, and ameliorated glucose intolerance in pre-diabetic HFC57 mice. Our results indicated that SZ-A had a novel inhibitory activity on α-glucosidase, especially on disaccharidases. SZ-A at a single dose significantly reduced the peak of blood glucose elevation and delayed the increase of blood glucose in normal and diabetic mice after disaccharide and polysaccharide loading. Long-term SZ-A treatment improved glucose and lipid metabolic profiles by delaying carbohydrate absorption from the intestine and reduced the postprandial blood glucose levels in both pre-diabetic and diabetic animal models. Therefore, SZ-A application may display a beneficial role in preventing the development and complications of diabetes.
Network pharmacology and rat ischemia-reperfusion injury (MIRI) model was used to analyze the mechanism of cardiac protection by Trichosanthes. The animal experiments were approved by the Medical Ethics Committee of Wannan Medical College. Compounds were screened by TCMSP database and TCM Database@Taiwan according to oral bioavailability (OB > 30%) and drug like activity (DL > 0.18). The PDBID value of the compound (Z'-score < 0.5) was obtained in DRAR-CPI database and converted into a target protein by UniProt database. Human genes of target proteins were identified using the term "myocardial ischemia reperfusion injury" as the keyword through the CoolGeN database. GOTERM_BP _DIRECT enrichment analysis of target proteins related to MIRI and KEGG PATHWAY annotation analysis were performed using the DAVID database. The component-target protein-signal pathway network was constructed using Giphi0.9.2 software. The expression of mitogen-activated protein kinase (MAPK) signaling pathway-related proteins in MIRI rats pretreated with Trichosanthes (0.2, 1.0 and 2.0 g·kg-1) was analyzed by Western blot with compound Danshen (85.05 mg·kg-1) as a positive control. Network pharmacology found that 12 compounds, including schottenol in Trichosanthes, synergistically inhibit MIRI through multiple targets or biological pathways, involving target proteins such as extracellular regulated protein kinase 2 (ERK2), c-jun-N-terminal kinase-1 (JNK1) and p38MAPK in MAPK signaling pathways. Western blot results showed that phosphorylation of ERK1/2 was dose-dependently up-regulated in MIRI rats pretreated with Trichosanthes, while the level of p38MAPK or JNK1 phosphorylation was down-regulated in a dose-dependent manner. Compared with the control group, phosphorylation of ERK1/2, JNK1 and p38MAPK protein showed significant difference in medium and high dose groups (1.0 and 2.0 g·kg-1) (P < 0.01). Therefore, Trichosanthes could play an anti-MIRI role by regulating phosphorylation of ERK1/2, JNK1 and p38MAPK proteins in rats. In conclusion, the targets and pathways of Trichosanthes on anti-MIRI were revealed by network pharmacology and verified in rat MIRI model, providing the scientific basis for further study on the mechanism of Trichosanthes for cardiac protection.
This study was designed to compare intestinal bacteria and inflammatory cytokine expression in rats with ulcerative colitis (UC) after treatment of three regiments, Huang-qin-tang (HQT), Si-shen-wan (SSW), and Tong-xie-yao-fang (TXYF). After approved by Institute of Chinese Materia Medica Ethics Committees in China Academy of Chinese Medical Sciences, UC in rats was induced by using a compound method (trinitrobenzenesulfonic acid plus ethanol). Rats were randomly divided into control, disease, positive control salazosulfapyridine (SASP, 0.5 g·kg-1), HQT (20 g·kg-1), SSW (26 g·kg-1), and TXYF groups (22 g·kg-1). After 7 days of treatment, colonic tissues and the blood were taken for various assays. Damage of colonic tissues was detected by H & E staining. The levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E2 (PGE2) in the serum were detected by the enzyme linked immunosorbent assay (ELISA). Total DNA was extracted from stool samples for analyses of 16SMiseqPE300V3-4 segment using high-throughput sequencing. The inflammatory cytokine results showed that compared with the disease group, the content of IL-6, PGE2, TNF-α in SASP group were decreased (P < 0.05), with the most significant decrease being the level of IL-8 (P < 0.01), whereas the levels of IL-6, IL-8 and TNF-α in HQT group were reduced (P < 0.05) and PGE2 content was clearly reduced (P < 0.01). The contents of four cytokines in SSW group were decreased, but there was no statistical difference. While the levels of IL-6 and TNF-α in TXYF group were reduced, and the reductions of IL-8 and PGE2 were significant (P < 0.05). The results after sequencing showed that microbiome species richness SSW group > HQT group > TXYF group; the similarity between samples TXYF group > SSW group > HQT group; the species of HQT and TXYF group have greater difference when compared to the disease group. The content of beneficial bacteria in the intestine of HQT group > SSW group > TXYF group. Three regiments all have therapeutic effects on UC, manifested by improvements of the signs and mental status of UC rats. However, in terms of inhibition of inflammatory factors IL-6, IL-8, PGE2 and TNF-α, and regulation of intestinal microbiome, the therapeutic effect of HQT was superior than SSW and TXYF.
Foxo-1 plays an important role in development of muscle atrophy, serving as a potential target for therapeutic treatment of the disease. In this study, the Foxo-1 mRNA was targeted by a Foxo-1 specific RNA oligonucleotide modified by 2'-O-methyl and with a butanol tag at the 3'-end. To understand the in vivo significance of new modified RNA oligos, efficacy, pharmacokinetic and safety profiles of the new modified RNA oligonucleotide targeting Foxo-1 were evaluated in mice. All experimental protocols were approved by the Animal Ethics Committee of Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention. The results showed that different doses of the RNA oligonucleotide can reduce the expression of Foxo-1 in mice by two routes of administration, leading to an increase in skeletal muscle mass of the mice. The results of pharmacokinetic evaluation showed that the plasma disappearance curve for the RNA oligonucleotide could be described by a two-compartmental model. The results of safety evaluation showed that no obvious adverse effects on renal and hepatic functions, nor on hematological parameters by intravenous or oral administration of the RNA oligo with a maximum dose of 30 mg·kg-1. Histopathology also did not reveal any significant changes in the morphology of the organs studied. In conclusion, the new modified RNA oligo is safe and effective in mice, providing experimental evidence supporting the significance for its clinical application.
Using column chromatographic and preparative HPLC technologies, we isolated a new sesquiterpene glycoside from the stem of Dendrobium nobile. With spectroscopic techniques including NMR and MS, the new compound was identified as cadalene-12-O-β-D-glucopyranoside. This type of compound was dehydrogenated from cadinane sesquiterpene to achieve a naphthalene ring, and it is rare from a natural resource.
The chemical constituents of Viburnum taitoense Hayata were investigated using column chromatography silica gel and Sephadex LH-20, etc. Seven pentacyclic triterpenoids were isolated and their structures were elucidated by spectral data and physicochemical properties as 3β, 6β-dihydroxy olean-11, 13(18)-dien-28-acid (1), 3β-hydroxy olean-11, 13(18)-diene-28-acid (2), 12-ene-olean-28-acid-3β-palmitate (3), 3β-acetylcocodiol (4), corosolic acid (5), uvaol (6) and ursolic acid (7). Among them, compound 1 is a new oleanane type triterpenoid and its absolute configuration was confirmed by single-crystal X-ray diffraction data. Compounds 2-5 were isolated from this genus for the first time. All the compounds were evaluated for their anti-inflammatory activities in vitro, and compound 5 showed significant inhibitory activity against nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells with an IC50 of 25.52 ±0.56 μmol·L-1 when compared to the positive control, quercetin (IC50 of 25.46 ±0.62 μmol·L-1).
In this study, we accurately collected the embryonic parenchyma cells and endocarp stone cells of Arctii Fructus at five different growth stages by laser microdissection. Quantitative analyse of caffeic acid, arctiin and arctigenin in these cells were performed using ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS). The results showed that a large amount of arctiin was produced and accumulated in embryonic parenchyma cells from the late flowering stage to mature stage, while much lower content of arctiin was produced and accumulated in endocarp stone cells at these stages. It suggested that the biosynthetic pathways of arctiin were different in embryonic parenchyma cells from endocarp stone cells of Arctii Fructus. Arctigenin was found to be produced and accumulated in both embryonic parenchyma cells and in endocarp stone cells from the late flowering stage to mature stage, but it reached a peak in endocarp stone cells at late flowering stage, then decreased slowly. The concentration of arctigenin was far less than that of arctiin regardless of embryonic parenchyma cells or endocarp stone cells. These results have validated the new method for analysis of dynamic accumulation of arctiin in Arctii Fructus by UFLC-MS/MS with frozen sections and microdissection.
In this manuscript, a rapid and simple analysis method for aconitine alkaloids was established. The method was based on the use of direct ionization and wooden tip spray ionization technology to detect the aconite. The aconite tuber slices were wrapped with wet filter paper overnight, cut into triangles, and extracted with a few solvents for direct ionization and wooden tip spray mass spectrometry. The results showed that alkaloids in aconite tuber can be rapid detected by two mass spectrometric methods without tedious sample pretreatment. Both methods are superior to that of traditional capillary electrospray ionization mass spectrometry (ESI-MS). The direct ionization MS is better than the wooden tip spray MS for analysis of aconite except under the condition of methylene chloride as extract or spray solvent. Different types of alkaloids in aconite tuber can be selectively detected when different solvents are used. The experiments provide a rapid and no pretreatment MS spectrometric method for analysis of alkaloids in aconite. These sample methods are important for research on aspects of plant varieties, storage, prescription compatibility, and quality control of aconite.
To establish a quality evaluation method for Astragali Radix using polysaccharide as quality control index, we established the Astragalus polysaccharide and monosaccharide sugar spectra, and combined with immunological activity test. High performance liquid chromatography (HPLC) was used to establish the specific chromatograms of Astragalus polysaccharides and monosaccharides. The data were analyzed by multivariate statistical analysis and cluster analysis using SIMCA software and SPSS software to distinguish Astragalus membranaceus var. mongholicus from different habitats or planting methods. The activity was evaluated by testing mouse peritoneal macrophage phagocytosis using neutral red. The results showed that the content of polysaccharides and the ability of enhancing phagocytic activity of macrophages from imitation wild Astragali Radix in Shanxi Hunyuan was higher than cultured Astragali Radix. The polysaccharides of Astragali Radix from Shanxi Hunyuan, Shanxi Wuzhai and Gansu Longxi have similar molecular weight distribution, but the peak area of each part has a significant difference in the percentage of the total peak area. The part of the polysaccharide of Shanxi Astragalus membranaceus with a molecular weight of about 10 kDa is higher than that of Gansu. Principal component analysis (PCA) shows that Astragali Radix from Shanxi and Gansu can be separated. All three are composed of five monosaccharides such as rhamnose, glucose, galactose, arabinose and galacturonic acid. However, the Astragalus polysaccharides (APS) in the three regions have different ratios of monosaccharide substances. The PCA display can distinguish three different Astragalus membranaceus var. mongholicus. This study used a combination of fingerprint of carbohydrates and the effects of APS on cellular immune function to provide a basis for quality evaluation and quality control of different habitats or planting methods.
CY-1-4 is a tryptanthrin derivative exhibiting antitumor activity. The solubility of CY-1-4 was poor and the corresponding mechanism needs further study. To solve this problem, we prepared nanoparticles encapsulated with CY-1-4 (CY-1-4 NPs) by nanoprecipitation method using poly(caprolactone) (PCL) and poly(ethylene glycol)-co-poly(ε-caprolactone) (PEG-PCL) as carriers to improve solubility. We then explored whether CY-1-4 NPs induced B16-F10 cytotoxicity via ferroptosis by determining the effect of CY-1-4 NPs on reactive oxygen (ROS) levels, repairing efficacy of lipid reactive oxygen inhibitor ferrostatin-1 and iron chelator deferoxamine (DFO), and potentiation of protoporphyrin (PPIX) induced B16-F10 cell death. The results showed that nanoparticlated strategy significantly improved solubility of CY-1-4. With the particle size about 116 nm, encapsulating efficacy was about 83% and the drug loading capacity was about 4.80%. Ferroptosis mechanistic studies indicated that CY-1-4 NPs could improve the ROS level in B16-F10 cells, whereas ferrostatin-1 and DFO could partly inhibited the cytotoxicity and PPIX could potentiated the cytotoxicity of CY-1-4 NPs in B16-F10 cells. These results showed that ferroptosis was one of the cell death mechanisms induced by tryptanthrin derivative CY-1-4 nanoparticle.
Immunotherapy is the most active research area for cancer treatment. Tumor vaccine is one of the most developed aspects of cancer immunotherapy. Though tumor vaccine has made many breakthrough, it still faces many challenges. In this study, we coated the black phosphorus quantum dots (BPQDs) with cancer cell membrane to create a nanoparticle named BPQD-CCNVs. The BPQD-CCNVs were incubated with bone marrow-derived dendritic cells and irradiated with 808 nm infrared light. We tested the expression level of CD80, CD86 and MHC Ⅱ of dendritic cells by flow cytometry after irradiation. All animal experiments approved by the Animal Experiments Ethical Committee of Tsinghua University. The results showed that the rise of medium's temperature caused by the photothermal effect of BPQDs could upregulate the expression of CD80, CD86 and MHC-Ⅱ on dendritic cell surface. Based on these, we conclude that near infrared irradiation can stimulate the activation of dendritic cells. Our study may have provided a new strategy for tumor vaccine development.
Microspheres based on polylactic acid-glycolic acid (PLGA) copolymer have unique advantages in pulmonary controlled drug delivery. However, the clearance mechanism dominated by lung macrophage phagocytosis greatly limits the long-term retention of drugs in the deep lung. In order to avoid the scavenging effect of lung macrophages, the PLGA microspheres coated by polyethylene glycol-distearoyl-glycero-phosphoethanolamine (PEG-DSPE) was designed in this study, and the effect of chain length of PEG-DSPE and its ratio on the macrophage uptake was investigated. With coumarin 6 as a fluorescent probe, the coumarin 6-loaded PLGA microspheres was prepared by premix membrane emulsification/solvent evaporation. The particle size was controlled to 3-5 μm and the encapsulation efficiency was over 90%. After incubation in the cell culture fluid for 48 h, the in vitro leakage of fluorescein from the microspheres was less than 1.5%, eliminating the interference of free fluorescein on the cellular uptake. Murine macrophages RAW264.7 cell line was selected for the in vitro cell study. The preparations showed little toxicity to cells in the cytotoxicity study. Results of the macrophage uptake study showed that PEG5000-DSPE and PEG10000-DSPE coated groups with both high and low proportions (PEG-DSPE/PLGA 1:1, 0.25:1) could significantly reduce the phagocytosis of macrophages to microspheres compared with the uncoated PLGA group. For PEG2000-DSPE coated microspheres, the effect of escaping macrophage phagocytosis could be achieved by increasing the ratio of polyethylene glycol (PEG) on the surface of particles. Overall, the chain length of PEG-DSPE and its ratio are the key factors affecting the macrophage uptake. In pulmonary controlled drug delivery, high molecular weight of PEG-DSPE (PEG5000-DSPE and PEG10000-DSPE) and the high ratio (PEG-DSPE/PLGA 1:1) of PEG2000-DSPE can be selected to escape the phagocytosis of alveolar macrophages and prolong the drug retention in the lungs.
Codeine-O-demethylase (CODM) is a key enzyme in the biosynthesis of codeine and morphine. In this study, CODM gene sequences were cloned from Papaver somniferum and Papaver rhoeas, and were compared with each other by sequence alignment and bioinformatics analysis. The results showed that there were three genotypes of CODM in Papaver somniferum and five genotypes of CODM in Papaver rhoeas. Bioinformatics analysis showed that all CODM proteins had no signal peptide sequence, and these proteins were predicted to be non-secretory proteins, belonging to the Pcbc supergene family. Although the amino acid sequences of CODM in poppies are the same, the expression levels of CODM in different poppy resources are significantly different. It is speculated that the variation of transcription level of CODM may be related to its non-coding region sequence, which lays a foundation for further research on the synthesis and regulation mechanism of alkaloids in poppies.
The number of clinical trials for mesenchymal stem cell (MSC) products ranked the top among all stem cell products, with more than 900 trials ongoing or completed by 2018. In China, many MSC clinical trials have started as "the third type of medical technique" and the dossiers of MSC products have been submitted to National Medical Products Administration (NMPA). The biological function and therapeutic effect of MSCs are constantly being recognized in scientific communities. However, the observed functions of MSCs in vitro are not fully reproduced in the living microenvironment in vivo. There are substantial variations among tissue origins, cellular phenotypes and biological functions. Different formulations, delivery methods, manufacture processes or doses all greatly affect the clinical efficacy. It is difficult for MSCs to maintain the naive state due to the differences between in vitro culture conditions and in vivo microenvironment. Meanwhile, there is no widely accepted scientific definition for MSCs until now, due to the complexity of manufacturing process and variable sources. Consequently, the regulation of MSC products is a challenge for drug administrative agencies. In this article, we review the research progress of MSC products around the world, and summarize the considerations in evaluating the chemistry, manufacturing and controls (CMC) section of MSC product applications, with respect to raw materials, manufacture processes and quality control. We hope that the information summarized here will provide insights for the development and evaluation of MSC products.
To ensure the consistency of quality in recombinant protein production, the cell bank for biologics should be derived from a single clone. A number of techniques have been used for cloning and assurance from the cellular pool after transfection with a target gene. Here, using CHO cell as an example, we summarize the knowledge and understanding of monoclonality of production cell bank from both industries and regulatory authorities, and propose general considerations on the requirements of monoclonality for clinical trial application and new drug application based on current techniques. Furthermore, we suggest quality control strategies and assessment methods for those cell banks from non-single clones.