Lipid droplets (LDs) are ubiquitous dynamic organelles that store and supply lipids in all eukaryotic and some prokaryotic cells for energy metabolism, membrane synthesis and production of essential lipid-derived molecules. There is increasing evidence that hepatitis C virus (HCV) has co-evolved due to its lack of lipid biosynthetic pathways to utilize host lipid metabolic pathways to establish a suitable environment for virus proliferation and obtain the necessary components, eventually promote the assembly and transportation of virus. In this review, we outline the relationship between HCV life cycle and lipid droplet biosynthesis and metabolism, with the aim to discover potential antiviral targets for development of new therapeutic interventions.

Ferroptosis is a novel type of regulated cell death with morphology, biochemistry and mechanisms differing from traditional cell death types such as apoptosis, necrosis and pyroptosis. The regulatory mechanisms of ferroptosis mainly involve iron metabolism, amino acid metabolism and lipid metabolism. It has been found that ferroptosis plays a key role in the pathogenesis of diseases including neurodegenerative diseases, malignant tumors and ischemic reperfusion injury. Parkinson's disease (PD) is one of the most common neurodegenerative diseases and its etiology and pathogenesis remains unclear. Recent studies revealed that ferroptosis might be involved in the pathogenesis of PD, as evidenced by high iron content, depletion of reduced form of glutathione and elevated levels of lipid peroxides detectable in the midbrain of PD patients. Both in vitro and in vivo models of PD have shown that some ferroptosis inhibitors have the ability of attenuating the symptoms and one iron chelator is undergoing a clinic trial. We here summarize the mechanisms of ferroptosis and its association with PD, in an effort to suggest potential novel targets for therapies of PD.

Reprogramming of metabolism is one of the most critical features in tumorigenesis and tumor growth. Many types of cancer show an increased demand for specific amino acids, rely on exogenous supplies, or alter amino acid metabolic pathways, leading to changes in corresponding amino acid levels to meet the need of tumorigenesis. Therefore, if the level of tumor growth-dependent amino acids can be effectively controlled, a new treatment strategy can be developed from the perspective of cell metabolism. At present, remarkable progress has been made in this field. This paper outlines the amino acid metabolic pathways closely related to tumorigenesis and tumor growth, and summarizes the corresponding regulatory mechanisms and active molecules. Finally, the direction of the field is discussed and prospected for future development.

Pyrrolizidine alkaloids (PAs) are a class of hepatotoxic compounds that are largely found in plants. "Zicao" is one of the most commonly-used Chinese herbal medicines from multiple sources, owing to its anti-inflammatory and wound healing effects. However, many studies have shown that this herb and its relative species contain hepatotoxic PAs. These PAs may cause hepatic sinusoidal obstruction syndrome following metabolic activation, and are therefore considered as potential toxic substances. Even though the toxicity of "Zicao" in clinical use has not been reported, the existence of PAs will undoubtedly post a threat for its safety in long-term use. It has now become the focus of many researchers to disclose and prevent its potential risk of intoxication. This review summarizes recent progress and key scientific evidence found in the research of pyrrolizidine alkaloids from "Zicao" and its relative species, including their metabolic toxicity. We comment on the need of future studies, such as providing a reference or guidance for safety evaluation of this medicinal herb in clinical practice.

Covalent tyrosine kinase inhibitors (TKIs) can inhibit the signaling pathway of tumor cells by covalent binding with cysteine residues of target proteins, which has the advantages of high potency, extended duration of action and overcoming drug resistance. In this article, we will review the metabolism and pharmacokinetics of some covalent TKIs. Currently, the covalent TKIs approved by US food and drug administration (FDA) are afatinib, neratinib, dacomitinib, osimertinib, ibrutinib and acalabrutinib. Pyrotinib have been approved by National Medical Products Administration (NMPA) to reach the market recently. Covalent TKIs can covalently bind with plasma proteins, especially human serum albumin, thus effected the pharmacokinetics of these drugs.

As a part of novel drug delivery carriers, peptides have diverse biological activities, low immunogenicity and good biocompatibility. In recent years, studies on the delivery carriers modified by peptides have attracted much attention. Among them, the peptides with acid sensitivity can change their secondary structures under slightly acidic microenvironment of the tumor or in lysosome. Therefore, the carriers made or modified by acid-sensitive peptides can specifically release the loaded drug in the tumor tissue, enhance the cell internalization of drugs and improve its therapeutic effects. In accordance with acid-sensitive peptides studied, the side chains, number of polar residues, sequence and secondary structure of the peptides might be involved in the acid sensitivity. In this review, we summarize the acid-sensitive peptides from recent literatures, analyze the connection between the structure and the acid sensitivity, and focus on the mechanism and application of acid-sensitive peptides in drug delivery. This provides the basis for further development and utilization for acid-sensitive peptides for efficient drug delivery.

Hemorrhagic transformation (HT) is a frequent complication of ischemic stroke, especially after thrombolytic therapy. This event is associated with increased morbidity and mortality. Tissue plasminogen activator (t-PA), the only FDA proved drug for breaking blood clots, is underutilized in ischemic stroke, because of its limited therapeutic window and hemorrhagic complications. Due to the lack of clear understanding of the pathological mechanism, there are no effective drugs to decrease the incidence of HT. Pinocembrin is a natural flavonoid compound and has neuroprotective effects in animal ischemic stroke models. In this study, we investigated the role of pinocembrin in t-PA thrombolysis-induced HT in rat thromboembolic stroke model. t-PA was administrated 6 h after ischemia and pinocembrin (5, 10 and 20 mg·kg^-1) was given 5 min before t-PA administration. Infarct volume, neurological score and hemoglobin content were evaluated at 24 h after ischemia. Evans blue leakage was used to detect blood-brain barrier (BBB) permeability. All procedures were approved by the Institutional Animal Care and Use Committee of the Peking Union Medical College. The results showed that treatment with t-PA at 6 h after ischemia aggravated brain injury and increased the risk of HT, with infarct volume and brain water content reached 39% and 83.4%, respectively. Pretreatment with pinocembrin decreased the infarct volume and brain water content to 28.5% and 80.3%, and improved neurological function. In addition, the combined application of pinocembrin with t-PA reduced hemoglobin content and Evans blue content in brain tissue by 50% and 40%, indicating that pinocembrin could protect the BBB permeability and reduce the occurrence of HT. Among these doses, 10 mg·kg^-1 is most effective. In conclusion, our results demonstrate that the combination of pinocembrin with t-PA protects against cerebral ischemia, reduces the occurrence of HT induced by t-PA thrombolysis. Thus, pinocembrin may be a potential therapeutic drug for t-PA induced HT.

The purpose of this study is to further explore the effects of SI-4650, a newly discovered small molecule inhibitor of spermine oxidase (SMO) in our laboratory, on proliferation and migration of human osteosarcoma 143B cells and its underlying molecular mechanism. Chemiluminescence and high performance liquid chromatograph were used to analyze the effect of SI-4650 on SMO activity in 143B cells. DCFH-DA-staining/FCM was used to analyze the accumulation of cellular reactive oxygen species (ROS), whereas MTT and FCM were used to detect proliferation and cell cycle. Transwell culture and Western blot were used to analyze the expression levels of migration-related proteins. PI/FITC-Annexin V/FCM, fluorescence microscopy and Western blot were used to analyze apoptosis and autophagy. Our results showed that SI-4650 could significantly decrease SMO activity, inhibit cell proliferation or migration, and induce a S-phase cell cycle arrest in 143B human osteosarcoma cells. The mechanism may be related to interfering with polyamine metabolism, activating mitochondrial-mediated apoptosis and causing autophagic death. These results suggest that SI-4650 has the potential for clinical use in treatment of osteosarcoma.

Alterations of mitochondrial structure and function in tumor cells allow cell survival and proliferation under hypoxic and acidic microenvironment. The effect of normal mitochondria on tumor initiation and development remains unknown. In this study, mice were euthanized by rapid cervical dislocation for isolation of hepatic mitochondria, which were injected intravenously to melanoma-bearing mice. This animal experiment had been approved by Southwest University Experiment Animal Ethics Review Committee. The results showed that exogenous mitochondria can significantly inhibit the growth of melanoma. Mitochondria isolated from the liver of young mice had more potent anti-melanoma effect than those isolated from aging mice. The average volume of tumors decreased significantly from 1.35 cm³ to 0.34 cm³, and the average mass of tumors decreased significantly from 0.63 g to 0.22 g. This anti-tumor mechanism might be associated with induction of mitophagy and cell necrosis after the exogenous mitochondria entering the melanoma cells. As mitotherapy can clinically improve somatic cell survival for treatment of pediatric patients with myocardial ischemia, the observed anti-tumor effect of exogenous mitochondria provides a hope for selective tumor treatment.

IMB5046 is a newly discovered nitrobenzoate functioning as a microtubule inhibitor. Here we report its synthesis and in vitro anti-angiogenic activity. IMB5046 was synthesized by conjugation of 2-morpholin-4-yl-5-nitrobenzoic acid with 4-(methylthio)benzyl alcohol via two-step reactions. The structure of the end product was verified using ¹H NMR and HR-MS spectroscopy. The effect of these compounds on cell proliferation was determined using MTT assay, and their impact on cytoskeleton was investigated using fluorescence assay. Flow cytometry was performed to examine the effect of IMB5046 on cell cycle. Cell wound scratch assay and Transwell assay were performed to examine cell migration. Endothelial tube formation assay was used to evaluate the anti-angiogenic activity of IMB5046. The results indicated that IMB5046 induced endothelial cell contraction and microtubule depolymerization, and inhibited the proliferation of endothelial cells and tumor cells, while two raw materials showed no obvious effects. IMB5046 arrested cell cycle at G₂/M phase, even at low-cytotoxic concentrations it significantly inhibited the motility of endothelial cells. IMB5046 inhibited the tube formation of endothelial cells according to the number of tubes and junctions. In conclusion, IMB5046 is a promising microtubule-targeting drug with anti-angiogenic activity.

The purpose of this study was to select the active compounds targeting Hsp90 protein in pancreatic cancer cells through a new dual "target + activity" rapid discovery technique. We combined an in vitro anti-cancer activity screening method with a dual-luciferase reporter gene and multi-chromatography separation technology, for rapid discovery of potential Hsp90 inhibitors from the Chinese herbal medicine Physalis angulata L. The anti-proliferation activity of those compounds was assessed in pancreatic cancer cell line BxPC-3 by MTT assays. The molecular mechanisms of Hsp90 inhibition were explored by Western blot and shRNA knockdown assays. As a result, two withanolides, withanolide E (WE) and 4β-hydroxywithanolide E (HWE), were identified from Physalis angulata L. The half maximal inhibitory concentration (IC₅₀) of WE and HWE were 0.71±0.03 and 1.23±0.10 μmol·L^-1 for the growth of BxPC-3 cells in 48 h. Luciferase reporter assay demonstrated that WE and HWE significantly induced heat shock element (HSE) activity in a dose-and time-dependent manner. The molecular mechanism study showed that after exposing to 5 μmol·L^-1 WE or HWE for 48 h, the aggregation of Hsp90 dimer was upregulated to 6.5±1.3 and 11.8±2.0 fold, while the expression of Hsp90 client protein Akt was downregulated to 21.7%±2.8% and 9.8%±1.4% of the control group. Moreover, the Hsp90 inhibitory activity of WE or HWE was canceled by shRNA mediated Hsp90 knockdown. Overall, based on the dual "target + active" rapid discovery technique, two new Hsp90 inhibitors WE and HWE were found from Physalis angulata L. The Hsp90 inhibitory mechanism of WE and HWE may be mediated by induction of Hsp90 aggregate dimer and inhibition of Hsp90 client protein Akt expression.

This study was designed to explore the interventional mechanism involving "multi-components, multi-targets and multi-pathways" of Gu-Chang-Zhi-Xie pills (GCZX) for treatment of irritable bowel syndrome (IBS) using pharmacological network technology. Firstly, 96 active ingredients from GCZX pills were screened by ADME parameter filtration and chemical space principal component analysis, and the targets of anti-IBS function were predicted using PharmMapper online database. Secondly, AutoDock Vina was used to validate the docking between the active ingredients and predicted disease targets, and to establish the corresponding relationship between "pharmacodynamic molecules and target proteins". Finally, the target elements were mapped into the KEGG biological pathway by CluoGO plug-in, which further elucidates the potential relationship between the key targets and the mechanism of action of Gu-Chang-Zhi-Xie pills for treatment of IBS. The results showed that most of the top 11 key pharmacodynamic molecules were isoquinoline alkaloids, which mainly acted on inflammatory or pain targets, with different degrees of anti-inflammatory and analgesic effects. A total of 39 key targets were identified, including TPH1, TNF-α, IL-6, IFN-γ, MAO-A and IL-10. These targets were mapped to 29 KEGG pathways, of which the P-value of 5-HT signaling pathway was the smallest. Therefore, the pharmacodynamic molecules mainly act on 6 core targets and may play a major role in the regulation of 5-HT signal synthesis or transport pathway. This study sets an example for drug development and mechanistic investigation using innovative technology.

Recently, hepatic sinusoidal obstruction syndrome (HSOS) caused by Gynura Rhizoma (Tusanqi) has gained global attention. The purpose of this research is to investigate the effects and mechanisms of Danning tablet, a traditional Chinese formula, on protecting against HSOS induced by Gynura Rhizoma. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. HSOS was induced by intragastrical administration of Gynura Rhizoma extract (1 g·kg^-1·d^-1) for 40 consencutive days. On the other hand, mice in the protection group were intragastrical administration of Danning tablet powder (3 g·kg^-1·d^-1) 4 hours before treatment of Gynura Rhizoma extract. The results showed that Danning tablet could significantly attenuate the liver injury in HSOS mice. Mice in the protection group showed decreased serum activity of spartate amino transferase, and levels of total bile acids and total bilirubin. In addition, the endothelial damage to the central venules, subendothelial hemorrhage, sinusoidal hemorrhage, and subendothelial fibrosis in HSOS mice were clearly attenuated in the protection group. Measurements of the key factors involved in liver fibrosis revealed that protection group showed significantly reduction in hepatic hydroxyproline concentration, mRNA expression of α-smooth muscle actin and fibrosis-related genes such as Collagen-1, Collagen-3, Mmp2 and Mmp9, as well as Smad3 phosphorylation (p-Smad) and serum transforming growth factor-β (TGF-β). Moreover, pro-inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, were also reversed in the protection group. All these results demonstrate the key roles of the TGF-β/p-Smad3 and inflammatory signaling pathways in the protection effect of Danning tablet on Gynura Rhizoma-induced HSOS, and pointing to the possibility of utilizing Danning tablet for protection against Gynura Rhizoma induced HSOS clinically.

To screen the antithrombotic effective components group of Trichosanthes extract, and to verify its pharmacodynamics and analyze its mechanism, the HPLC fingerprint of Trichosanthes extract (0.09, 0.45, 0.9 g·kg^-1) was established, and the pharmacodynamic indexes of antithrombosis in rats with aspirin (0.01 g·kg^-1) as positive control group were determined (the animals used in this experiment were approved by the Medical Ethics Committee of Wannan Medical College). The antithrombotic spectrum-activity relationship of Trichosanthes extract was studied and the effective antithrombotic ingredients group was screened by grey relational analysis. The monomer compound mixed solution (0.006, 0.03, 0.06 g·kg^-1) was prepared according to the content of each component in the active component group, and the pharmacodynamics and action mechanism were studied to verify the correctness of the spectrum-effect relationship. The correlation between the 22 components of Trichosanthes extract and antithrombotic efficacy was different and showed dose-effect relationship. Cytosine, uracil, guanine, hypoxanthine, xanthine, adenine, guanosine, and adenosine are the main antithrombotic components of Trichosanthes extract. The ratio of cytosine, uracil, guanine, hypoxanthine, xanthine, adenine, guanosine and adenosine was 3:12:10:5:2:8:13:14. Compared with the model group, the thrombus dry weight of each effective components group could be effectively reduced (P < 0.01 or P < 0.05), but there was no significant difference between each effective components group and the Trichosanthes extract group. Compared with the model group, the TXB₂ content in group (0.06 g·kg^-1, 0.03 g·kg^-1) could be effectively reduced (P < 0.01 or P < 0.05), and the content of 6-keto-PGF_1α could be increased in each group (P < 0.01), and the TXB₂/6-keto-PGF_1α tended to be normal and showed a dose-effect relationship. The effect was better than that in the Trichosanthes extract group (0.45 g·kg^-1) (P < 0.01). The effective ingredients group has a good antithrombotic effect, its mechanism is to inhibit platelet aggregation and improve vascular endothelial function.

The chemical constituents of Cydonia oblonga (Quince) seeds were investigated using chromatographic methods, including silica gel, Sephadex LH-20 and semi-preparative-HPLC. Eleven compounds were isolated and their structures were elucidated on 1D or 2D NMR, and HR-ESI-MS. These analyses have lead to identification of 5, 7-dihydroxy-2-n-pentacosanyl chromen-4-one (1), ursolic acid (2), tormentic acid (3), oleanolic acid (4), β-daucosterol (5), β-sitosterol (6), amygdalin (7), rutin (8), kaempferol (9), quercetin (10) and isoquercitrin (11). Among these, compound 1 is a new compound, and compounds 3, 5 were isolated from this plant for the first time. Compounds 1-4 and 8 showed significant PTP1B inhibitory activities with IC₅₀ value of 0.465, 16.14, 28.96, 23.78 and 11.70 μmol·L^-1, respectively.

Based on coumarin core structure as the procaspase-3 activator 1541 from our previous study, twelve coumarin derivatives bearing benzothiazole or benzene moiety were designed and synthesized. Target compounds were evaluated for in vitro antitumor activity against a procaspase-3 overexpressing cancer cell line (human histiocytic lymphoma cell, U937) and a procaspase-3 no-expression cancer cell line (human breast adenocarcinoma cell, MCF-7) to rule out off-target effects. The results revealed that coumarin derivatives bearing benzothiazole showed more potent inhibition activity and selectivity against procaspase-3 over-expressing cancer cell line (U937) than procaspase-3 low-sensitive cancer cell line (MCF-7). Caspase-3 activity evaluation showed that coumarin derivatives bearing benzothiazole showed remarkable caspase-3 activation activity, among them, compound 5f displayed the strongest activity with 93% degree. Flow cytometric assay revealed that compound 5f could inhibit proliferation of tumor cells by inducing apoptosis. Procaspase-3 activity assay showed that compound 5f showed strong procaspase-3 activation activity.

A sensitive and efficient liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitative determination of diflucortolone in rabbit plasma after dermal administration of diflucortolone valerate cream to rabbits. After extraction with ethyl acetate, the chromatographic separation was performed on Zorbax Eclipse XDB-C18 (50 mm×4.6 mm, 5 μm) with a gradient mobile phase consisting of 50% acetonitrile-50% methanol and 0.1% formic acid-5% methanol-5 mmol·L^-1 ammonium formate at a flow rate of 0.35 mL·min^-1. The quantitative analysis was carried out using multiple reaction monitoring (MRM) at specific ion transitions of m/z[M+H]⁺ 395.2→m/z 355.2 for diflucortolone and m/z[M+H]⁺ 258.1→m/z 120.9 for ethoxyphenylethylamine (internal standard) in positive ion mode with electrospray ionization (ESI) source. This validated LC-MS/MS method had a linearity over the concentration range of 0.01-10 ng·mL^-1 with the lower limit of quantification (LLOQ) at 0.01 ng·mL^-1. At level of LLOQ, the inter and intra-assay precision (RSD) were no greater than 9.82% and 11.0%, respectively. The main pharmacokinetic parameters of the diflucortolone including t_max, C_max, AUC_{0-72 h}, and t_1/2 were as follows:(6.33±1.21) h, (0.168±0.080 0) ng·mL^-1, (3.15±0.834) h·ng·mL^-1, (32.0±17.4) h. The method was validated in the pharmacokinetic study of diflucortolone in rabbit following dermal administration of diflucortolone valerate cream at dose of 0.01 g·cm^-2. In this study, the program of animal testing had been approved by Committee on the management and usage of experimental animal in the Evaluation Company of Innovative Drug, Tianjin Institute of Pharmaceutical Research.

This study aimed to evaluate the predictive performance of a vancomycin population pharmacokinetic model in 0-10 year Chinese pediatric patients. This study was approved by the Ethics Research Committee of the First Affiliated Hospital of Guangxi Medical University, data from hospitalized children ≤ 10 years of age who receiving vancomycin were collected retrospectively. Individual predictive values (IPRED) were estimated by Bayesian Analysis based on a previous published population pharmacokinetic model, and compared with the observed steady state trough concentration. As results, a total of 371 vancomycin serum concentrations from 191 patients were taken for the external validation. The mean error (ME), the mean relative prediction error (ME%), the mean absolute error (MAE) and the root mean square error (RMSE) in individual prediction method for the total patients were -0.50 mg·L^-1, 6.03%, 1.84 mg·L^-1, 2.86 mg·L^-1 respectively. The correlation coefficient between individual predictions and detection values was 0.95. The stability and the predictive performance of model were accepted by goodness-of-fit, visual predictive check (VPC) and Bland-Altman. The percentage of individual prediction error within ±30% was 82.75%. The above results suggest that, this Chinese pediatric population pharmacokinetic model in 0-10 years old has a good prediction performance. It can be applied to the design of initial treatment plan and predicting the extent of drug exposure.

This study aimed to evaluate the antioxidant activities of Scutellaria baicalensis Georgi flowers by measuring the scavenging activity of hydroxyl radical and superoxide anion radical. Aging of rats was induced by D-galactose and protective effects of Scutellaria flower extract (SFE) at different doses were evaluated by locomotor activities. To explore the mechanism of SFE, metabolomic technique combined with multivariate statistical methods was used to analyze the profile of metabolites from rat serum and quantify the levels of glutamine and glutamate in the serum. All research procedures were approved according to the Committee on the Ethics of Animal Experiments of Shanxi University. The results showed that high-dose of SFE had antioxidant activity in vitro, and could ameliorate the aging behavior of rats. A total of 9 potential biomarkers related to aging were found, pointing to the involvement of 7 metabolic pathways.

Carbon monoxide (CO) is an important chemical gas messenger molecule in the body with anti-inflammatory activity. As an active substance in gaseous state, the method for its safe and effective delivery towards the lesion sites remains to be established. Based on the natural affinity of carbon monoxide to hemoglobin, a main component of red blood cells (RBCs), this study proposes a carbon monoxide-red blood cell (CO-RBC) composite system, and tested its therapeutic effect against lung injury in an animal model. The mouse model of septic lung injury was adopted, and the carbon monoxide release molecule (CORM-2) was used as a positive control. CO-RBC system was characterized by CO release, stability, toxicity and in vivo lung targeting. The expression of intercellular adhesion molecule (ICAM-1) and pulmonary surfactant protein-A (SP-A) were evaluated in the animal model and the therapeutic effect of CO-RBC system for sepsis was measured by inflammatory factors tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), as well as survival time of mice and pathological changes of the lung. Our results show that CO-RBC system exhibited satisfactory stability with negligible CO release during 48 h storage under nitrogen protection, while the CO release was about 70% within 12 h under physiological condition, in contrast to CO burst release from CORM-2. The CO-RBC system showed no significant toxicity in the animal model, and in vivo fluorescence imaging results showed effective accumulation in the lungs, supporting its lung targeting effects. The secretion of TNF-α and IL-6 in the CO-RBC group was significantly lower than that in other groups, the degree of pulmonary interstitial edema was relieved, the white blood cell infiltration was decreased, and the survival rate was significantly improved. Therefore, the CO-RBC system has a significant inhibitory effect on the pulmonary inflammatory response in septic mice compared with CORM-2. This system provides a new hope for therapeutic treatment of sepsis.

To investigate the influences of zwitterionic polymer chain length on mucus permeability and cellular uptake, the nanoparticles (NPs) were coated with poly(sulfobetaine methacrylate) (pSBMA) with different chain lengths. The di-block polymer poly(ε-caprolactone)-block-poly(sulfobetaine methacrylate) (PCL-pSBMA) with different chain lengths were synthesized via atom transfer radical polymerization (ATRP) combining with ring-opening polymerization of ε-caprolactone, and corresponding nanoparticles (pSBMAn NPs) were prepared by nanoprecipitation method. The sizes of different pSBMAn NPs were around 100 nm, and zeta potential were about -7 mV. Mucin interaction or mucus penetration study based on transwell systems were employed to evaluate mucus permeability of NPs. Caco-2 cells and mucus-producing HT-MTX-E12 cells were employed to illustrate the endocytosis efficiency of pSBMAn NPs. The results showed that the permeability coefficient of NPs coated with shorter chain length of pSBMA (pSBMA₁₀ NPs) was only 42.83% of that coated with longer pSBMA (pSBMA₈₀ NPs). On the contrary, the cellular uptake of pSBMA₁₀ NPs was 2.44 fold higher compared to pSBMA₈₀ NPs. Although the cellular uptake of pSBMAn NPs was reduced in the presence of mucus, pSBMA₁₀ NPs still presented the highest cellular uptake. However, the in vivo results indicated that the oral bioavailability of pSBMA₂₀ NPs was higher than that of pSBMA₁₀ NPs. All animal procedures were performed in accordance with the Guidelines of the Sichuan University Animal Care and Use Committee and were approved by the Animal Ethics Committee of Sichuan University. This study provides a reference for oral delivery of zwitterionic nanoparticles.

Melatonin (MLT) is an endogenous chemical that has antitumor effects at high doses. However, it shows low oral bioavailability and short in vivo half-life, leading to drug resistance. Here, liposomal melatonin dry powder inhalers (LMD) were prepared, and were used for treatment of primary rat lung cancer by pulmonary delivery. Liposomal melatonin (LM) was prepared by the ethanol injection method to achieve an entrapment efficiency of 98.89%. LMD was obtained by freeze-drying after LM was mixed with mannitol. LMD appeared as spherical particles under a scanning electron microscope. The rehydrated liposomes had a small size of 65.15 nm and the zeta potential of -14.2 mV without change inentrapment efficiency. LMD had an aerodynamic particle size of 6.73 ±0.012 μm and a fine particle fraction (FPF < 8.06 μm) of 22.2%, suitable for pulmonary delivery. When administered with the same dose, LMD showed much higher inhibition on A549 lung cancer cells than MLT and gemcitabine. LMD of a large dose had no effect on the growth of normal lung epithelial cells (BEAS-2B). Rat lung cancer models were established after 45 days by instilling 3-methylcholanthrene (MCA) and N, N-dimethylnitrosamine (DEN) into the rat lungs once (the experiments had been approved by the ethics committee and carried out in accordance with relevant guidelines and regulations). Decreases of tumor nodules and inflammatory cells in the tumor-bearing rat lungs were observed after treatment of MLT, gemcitabine and LMD by pulmonary delivery compared with the models, wherein LMD was most effective. The efficiencies of inhibition of NF-κB p65, increase of Tunel detection (indicating enhancement of apoptosis), and decrease of malondialdehyde corresponded to LMD being most effective. Therefore, given the fact that LMD can deliver the drug into the tumor tissues of lungs, and it presents as a promising pulmonary inhalable regiment for treatment of lung cancer.

Disulfiram (DSF) is a traditional anti-alcohol drug, but it was recently found that DSF has strong inhibitory effect on the growth of a variety of cancer cells. However, its clinical application is greatly limited due to its poor solubility, instability in gastrointestinal tract and short plasma half-life. In this study, DSF is fabricated into nanosuspensions with the aim of trying to solve these problems. DSF nanosuspensions (DSF-NSps) were prepared by the anti-solvent precipitation method under ultrasonication, and the suitable stabilizer was screened according to the size, polydispersity index (PDI), and zeta potential of the resultant nanosuspensions, along with their particle size change during the storage at room temperature. The particle size, PDI, and zeta potential of DSF-NSps were determined using dynamic light scattering method, while the morphology of DSF-NSps was observed by transmission electronic microscope (TEM). The stability of DSF-NSps in media was examined according to their particle size change in different physiological media. The concentration of DSF was measured by HPLC assay. The in vitro drug release was evaluated on basis of dialysis. MTT assay was employed to evaluate the in vitro cytotoxicity of DSF-NSps against cancer cell lines. The 4T1 tumor-bearing mouse model was used to evaluate the in vivo therapeutic efficacy of DSF-NSps. All the animal experiments were acquired according to the Regulations for Animal Experiments and Guidelines for Ethical as defined by Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences and Peking Union Medical College. As a result, the combinational use of soyabean lecithin (SPC) and D-alpha tocopherol acid polyethyene glycol succinate (TPGS) was determined to best stabilize DSF-NSps when the ratio of DSF-SPC-TPGS was 24:20:4 (weight ratio), with small particle size and good storage stability. The resultant DSF-NSps showed a regular spherical morphology and drug loading content of (45.36 ±2.09)%, with average particle size of 175.00 ±0.75 nm, PDI of 0.24 ±0.07 and zeta potential of -14.3 mV. DSF-NSps displayed good particle size stability in a variety of biological media including phosphate buffer saline, normal saline, 5% glucose, artificial gastric fluid, artificial intestinal fluid and plasma, which would meet the demand of both intravenous and oral administration. The in vitro study demonstrated that nano-encapsulation greatly increased the stability of DSF in aqueous media, DSF-NSps exhibited sustained release of the encapsulated drug and significantly inhibited 4T1 cells compared to free DSF (IC₅₀, 1.07 vs 5.53 μg·mL^-1, P < 0.01). DSF-NSps showed a good dose-response relationship on the 4T1 tumor-bearing mice with the tumor inhibition rates at the three doses being 80.22%, 75.14% and 66.10%, all higher than that of paclitaxel injections (55.01%, P < 0.05). The in vivo biodistribution study displayed that DSF-NSps were mainly distributed into liver, spleen and tumor. In sum, disulfiram nanoparticles could be expected to provide an effective anti-cancer drug for the treatment of breast cancer.

Tropinone reductase Ⅰ (TRI) is a key branch point enzyme in the midstream of tropane alkaloids (TAs) biosynthesis pathway and represents an important target for TAs metabolic engineering, which can lead to metabolic flux of substrate tropinone to TAs. A novel TRI gene was isolated from Datura arborea, a woody resource plant, and designated as DaTRI2 (GenBank accession number is MH705164). The full-length cDNA of DaTRI2 with 1 135 bp exhibits a high sequence homology (96.8%) with DaTRI, and is predicted to encode a protein of 347 amino acids. Deduced DaTRI2 protein contain a conserved TGXXXGXG motif involved in NADPH binding, the catalytic N-S-Y-K tetrad motif and eleven amino acid residues important for binding to its substrate tropinone. The phylogenetic analysis revealed that DaTRI2 and other TRIs from Solanaceous plants belong to the same cluster and DaTRI2 exhibited closest phylogenetic proximity to TRIs from Datura. DaTRI2 was expressed in E. coli and the purified recombinant protein can catalyze both tropinone reduction and tropine oxidation with an optimum pH value of 8.0 and 9.6, respectively. When tropinone was used as the substrate, the K_m and V_max values of DaTRI2 at pH 6.4 were 210.05 μmol·L^-1 and 69.6 nkat·mg^-1 protein respectively, while the K_m and V_max values for tropine as the substrate were 188.03 μmol·L^-1 and 114 nkat·mg^-1 protein respectively, at pH 9.6. DaTRI2 transcript was most abundant in the young leaf, followed by the root. Cloning of DaTRI2 gene and biochemical analysis of recombinant DaTRI2 facilitate further research on the molecular mechanism on TAs biosynthesis in woody plants and provide a more potent candidate for TAs metabolic engineering.