Latest ArticlesThe size and surface morphology of carrier lactose had influence on the aerosolization performance of dry powder inhalers. In this article, chlorpheniramine maleate was blended with two types of commercial carrier lactose, which were Lactohale 100® and Respitose SV003® (SV003), as formulation model. In vitro experiments were conducted using fast screening impactor at 30 L·min-1 and 60 L·min-1 respectively. Meanwhile, computational fluid dynamics (CFD) coupling with discrete element modelling (DEM) was applied to discuss the movements of those two carrier particles in Handihaler® at the flow rate mentioned above. The dispersion characteristics of two formulations and the dispersion mechanism of Handihaler® were analyzed by establishing the relationship between in vitro experiments and numerical simulation. The results of in vitro experiments and CFD-DEM demonstrated that the aerosolization performance of formulation with SV003 was better. The linear correlation (R2=0.940 1) between fine particle dose and total energy loss by carrier collision within the wall of device was found by comparing the in vitro experimental results with CFD-DEM results. It revealed that particle-wall collision in Handihaler® had direct impact on the dispersion results of formulation.
Tenofovir disoproxil fumarate (TDF) is a nucleoside analogue that has been widely used for clinical treatment of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infection. The aim of this study was to investigate whether TDF has anti-Zika virus (ZIKV) activity in vitro. The inhibitory effect of TDF on ZIKV was detected by plaque reduction assay. Then, the anti-ZIKV activity of TDF at RNA level and protein level was verified by real time quantitative PCR and Western blot. Finally, MTT assay was used to determine the cytotoxicity of TDF. Our results showed that TDF not only reduced the formation of plaque after ZIKV infection, but also inhibited the replication of ZIKV RNA or expression of ZIKV NS2B protein. The 50% effective concentration (EC50) of TDF in inhibition of ZIKV replication were 14.96-27.47 μmol·L-1, while that of ribavirin was 56.01 ±12.16 μmol·L-1, which served as the positive control. The cytotoxicity of TDF and ribavirin in Vero cells were very low, with their 50% cytotoxic concentration (CC50) values being greater than 500 μmol·L-1. The therapeutic index of TDF calculated by CC50/EC50 was greater than 18.20, which was significantly higher than that of ribavirin. The results suggest that TDF has good anti-ZIKV activity in vitro and is expected to become a candidate drug for anti-ZIKV therapy.
Medicinal materials in China differ in quality by different ecological types. Our research group found that there were two ecotypes of domestic Panax quinquefolium L. according to the characteristics of ginsenosides, inside versus outside Shanhaiguan. The genetic and ecological mechanisms of quality variation of Panax quinquefolium L. is unknown. Based on the genetic-chemical-ecological strategy, transcriptome and HPLC technology were used for comprehensive correlation analyses of transcriptomic data, ginsenoside content and environmental climate ecological factors. The transcriptomic results showed that key genes of ginsenoside biosynthesis, such as HMGR, AS and FPS, were significantly down-regulated in the inside Shanhaiguan ecotype. HPLC results showed that the quality of outside Shanhaiguan ecotype Panax quinquefolium L. was higher than that of the inside ecotype, with the content of ginsenosides in outside Panax quinquefolium L. was higher than that of inside ecotype except Rb2. Correlation analyses revealed that content of Panax quinquefolium L. ginsenoside is positively related to the expression levels of ginsenoside biosynthesis key genes (MK, HMGS, HMGR, and AS), and negatively related to the expression of glycosyl transferase (GT). The content of ginsenosides is negative related with climate factors, such as temperature, sunshine, and is positively related with moisture in both ecological environments. This study has provided a new mechanistic insight into the quality variations of two ecotypes for Panax quinquefolium L. and established a scientific basis for studying the ecological factors for the quality of traditional Chinese medicine.
Natural products with diverse structures and significant biological activities were important source of lead compounds, and have played a key role in the innovative drug development. Recently, China has been in the prior position in discovering of structurally diverse active natural products from natural medicines. In 2018, a series of natural products with novel structures and significant biological activities have been isolated and studied by scholars from China, and 73 molecules with novel carbon frameworks have been selected as "Hot of The Press" by Nat Prod Rep Journal. In this review, the original, structures and biological activities of 123 compounds of natural products research field in 2018 were briefly described, which was aimed to exhibit the highlights of natural products research from China in past year.
About 15%-20% of drug-induced liver injury (DILI) will progress to chronic manifestation (CH-DILI), which sometimes advances rapidly to liver cirrhosis (LC-DILI) within 0.5-1 year with deteriorative clinical prognosis. Therefore, it is important to find a non-invasive diagnosis for early detection of liver cirrhosis. In this study, the metabolomic profiles revealed significant differences in the metabolites from the plasma of LC-DILI versus CH-DILI. We found 35 differential metabolites through principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). Through pathway enrichment analysis, some up-regulated metabolic pathways reflected impaired liver functions such as bile acid, lipid synthesis and decomposition during cirrhosis. Five biomarkers were found to exhibit effective diagnosis value (AUC > 0.6), including phosphatidylcholine, lysoPC (18:1 (9Z)), creatine, taurochenodeoxycholic acid and taurocholic acid. Furthermore, we found that the relative content ratio between phosphatidylcholine and lysoPC (18:1 (9Z)) had a better distinguishing ability (AUC=0.867). The relative content ratio also had the feature to reduce systematic errors of sample processing and instrument detection, therefore having a greater value for clinical application.
Aging is a normal physiological process involving coaction of many factors. The anti-aging effects of natural products have been studied by many domestic and international scholars, but not far enough, which still needed to be explored. Flavonoids, as natural products, have a variety of pharmacological activities and present in many traditional Chinese medicines. In recent years, research results indicate that flavonoids can delay the aging process of the nervous, immune, and reproductive systems, and the liver, skin and other tissues. The anti-aging effects of flavonoids have attracted more and more attention. Therefore, development of anti-aging drugs from flavonoids is of great significance to improve the quality of life for the elderly and slow the process of aging. However, the mechanism of the anti-aging effect of flavonoids remains unknown at present. This review will discuss the anti-aging effect and mechanisms of flavonoids in traditional Chinese medicine from the aspects of cellular signaling pathways and metabolic pathways based on the modern theories of aging.
Antiretroviral therapy has been used for treating AIDS with 31 single-target anti-HIV drugs currently on market. Searching for safe and effective of novel anti-HIV drugs remains a challenge worldwide. Multi-targets single-structure compounds referred to as designed multiple ligands (DMLs) have become a hot topic of producing anti-HIV drugs recently due to reduction in the likelihood of drug resistance, simplified dosing and improved patient adherence. Integrase (IN) and ribonuclease H (RNase H) are two indispensable enzymes in HIV republication, therefore are two important targets for developing anti-HIV drugs. Recently, diverse dual inhibitors of HIV IN and RNase H (IN/RNase H) have been developed via rational drug design and screening. This review summarizes the advances in chemically synthesized dual inhibitors of HIV IN/RNase H to provide the information for developing multi-targets anti-HIV drugs.
This study was designed to explore the antipyretic mechanism of Pueraria radix. The method of network pharmacology was used to determine the known ingredients corresponding to Pueraria radix, predict the drug-related gene/protein targets, and analyze the interplay between key ingredients and targets. Biological Information Annotation Databases (DAVID) was used to enrich the biological processes and pathways. The result of network analysis was validated by molecular docking. It was found that 49 active ingredients of Pueraria radix not only regulate 21 targets (e.g. PTGS2, EGFR), but also affect 11 biological processes (e.g. oxidation-reduction process, prostaglandin synthesis, positive regulation of fever generation and inflammatory response) and 7 metabolic pathways (arachidonic acid metabolism, serotonergic synapse and HIF-1, et al). Molecular docking results showed that more than 65% of the active ingredients could be well docked with key targets, and the relevant literatures indicated that the active components could inhibit the expression of PTGS2, which means the result has a high reliability. These results indicated that Pueraria radix may carry its pyretic action via a "multi-ingredients-multitargets-multi-pathways" mode, which provides a scientific basis for further research and drug development.
Lung cancer ranks the first in the mortality rate among all cancers, and non-small cell lung carcinoma (NSCLC) accounts for about 80% of the incidence of lung cancer. In recent years, the drugs targeting specific molecules have been developed rapidly. The epidermal growth factor receptor-tyrosine kinase inhibitors (EGFRTKIs) have achieved good results in the treatment of patients with NSCLC. Currently, there are three generations of EGFR-TKIs, and the treatment outcome of these drugs surpasses traditional chemotherapies. However, the problems of acquired resistance remains in the course of treatment. In this review, research progress of the mechanisms of acquired resistance is divided into two parts:EGFR-dependent pathway and EGFR-independent pathway. The EGFR-dependent pathway mainly includes EGFR gene mutations, whereas the EGFR-independent pathways include HER2 amplification, BIM deletion, activation of HGF/c-Met pathway, activation of IGF1R, RAS mutation, PTEN deletion, epithelial-mesenchymal transition, PUMA loss, and high levels of expression of VEGF or IL-6. These interconnected mechanisms are linked with acquired resistance to EGFR-TKIs in NSCLC.
Cellular energy metabolism disorder caused by dysfunction of nutrient utilization and mitochondrial damage contributes to a variety of diseases, including neurodegenerative diseases, cancer, metabolic diseases, and cardiovascular diseases. Understanding the effects of energy metabolism on diseases will help to improve our knowledge about disease etiology and may serve to develop strategies to delay disease progress. There are many compounds developed for targeting energy metabolism disorders, such as small molecules targeting the 18 kDa transporter (TSPO) for treatment of Alzheimer's disease, glucagon-like peptide-1 analogues for treatment of Parkinson's disease, inhibitors of glucose transporter 1 (GLUT1) and lactate dehydrogenase A for treatment of tumors, the fibroblast growth factors based treatment for type 2 diabetes (T2D), selective ligands of peroxisome proliferator-activated receptor (PPAR)-β/δ for treatment of cardiovascular diseases. We review here the abnormal energy metabolism of common energy metabolism disorder-related diseases, summarize the potential targets that may be used for new drug discovery, and the strategies for alleviating the disease process by improving energy metabolism.