Latest ArticlesReprogramming 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.
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.
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 Km and Vmax values of DaTRI2 at pH 6.4 were 210.05 μmol·L-1 and 69.6 nkat·mg-1 protein respectively, while the Km and Vmax 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.
To investigate the potential hypoglycemic effect of nanosuspensions of honokiol and explore the underlying mechanisms, a high fat diet (HFD) was studied in C57BL/6J mice divided into five groups:normal diet (ND), HFD, HFD/honokiol-sodium carboxymethyl cellulose (CMC-Na) (Hono-CMC, 100 mg·kg-1), HFD/honokiol-Nano (Hono-Nano, 80 mg·kg-1), HFD/metformin (HFD/Met, 200 mg·kg-1). Fasting blood glucose (FBG) and body weights (BW) of mice were measured every seven days. After 30-day treatment, an oral glucose tolerance test (OGTT) was performed, and blood and tissue samples were collected for analysis. All animal experiments were approved by the Research Animal Care Committee of Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine. The data showed Hono-Nano and metformin reduced FBG, BW, and markedly improved OGTT of mice compared to HFD group (P < 0.05). Hono-CMC produced nonsignificant impact on FBG, BW of mice, while OGTT of mice was improved by Hono-CMC (P < 0.05). Meanwhile, none of these treated groups showed significant effects on regulating serum insulin levels, but all of them exhibited decreased serum glucagon levels notably compared to the HFD group (P < 0.05). Western blot analysis revealed that honokiol up-regulated levels of p-AMPK and p-FOXO1 in liver tissue of HFD mice (P < 0.05), which resulted in activation of AMPK and inhibition of FOXO1. Moreover, the expression of PEPCK (a key enzyme of gluconeogenesis) was decreased by honokiol (P < 0.05). Taken together, our findings demonstrate that nanosuspension of honokiol is more effective than CMC-Na-suspension of honokiol on blood glucose controlling in HFD mice. The hypoglycemic effects of honokiol might rely on suppressing hepatic gluconeogenesis via activating AMPK and inhibiting FOXO1.
Q-marker is a new concept of quality control for traditional Chinese medicine. Since its introduction in 2016, it has received extensive support and participation from researchers and manufactures of the entire industry. In order to establishing the research level of quality markers, normative research model, we review the proposed core theory and research methods of Chinese medicine quality markers. The definition and scientific connotation of Chinese medicine quality markers are analyzed. The core theories and research methods of quality markers are summarized from five aspects:"effectiveness", "specificity", "transfer and traceability", "compatibility environment" and "measurability" of quality markers. This paper aims to provide useful theoretical and methodological guidance for studying Chinese medicine quality markers.
The blood-brain barrier (BBB) not only maintains the stability of the environment within the central nervous system by controlling the transport of substances on both sides of the blood and brain, but also plays an important role in the R&D of new drugs for neurological disorders. The establishment of an in vitro high-fidelity model to study BBB function is imperative for assessing barrier permeability of drugs and xenobiotics. However, the complexity of the BBB structure makes it difficult to replicate with an in vitro model. Compared to the traditional in vitro BBB model, the BBB-on-chip provides certain advantages in miniaturizing the system, reducing the amount of cells and medium required, and allowing simultaneously induction of shear stress. We review here the BBB-on-chip models from their establishment and characterization to applications in research of neuroinflammation, brain tumor and drug evaluation.
Chemical constituents from the ethanol extract of Radix Angelicae Pubescentis was isolated and purified through Diaion HP-20 macroporous, silica gel column chromatography, gel filtration over Sephadex LH-20 and preparative HPLC. Two new sesquiterpenoid derivatives were identified as angesesquid A (1) and angesesquid B (2), and their structures were determined. In vitro degeneration model of primary rat disc chondrocytes was used to evaluate the anti-inflammatory activity of these two compounds. The results showed that compounds 1 and 2 had no anti-proliferation effect. Both compounds inhibited the release of NO, but had no inhibitory activity for the release of PGE2. This finding implies that both of these two new sesquiterpenoids could moderately inhibit the inflammatory reaction to some extent.
Ionic liquids are not limited to the traditional use of solvents because of their high permeability and excellent physicochemical and unique biological properties. Nowadays, with the deep understanding of their toxicity and biocompatibility, ionic liquids have been tailored as novel solutions to address potential problems of marketed drugs. Based on the research and development of modified new drugs, ionic liquids have been incorporated into drug synthesis and emerged as attractive environmental-friendly reaction media with milder reaction conditions, higher yields and easier reaction workups and drug delivery systems. In addition, they have been designed for effective drug carriers removing undesirable properties of solid drugs. Further, ionic liquids forming active pharmaceutical ingredients dedicated to the liquefaction of drugs for promising clinical applications.
The quality of traditional Chinese medicine (TCM) is the lifeline for TCM industry. The development of artificial intelligence (AI) has provided new means for the quality management of Chinese medicinal materials (CMM). In this paper, we take the quality marker (Q-marker) as a breakthrough point, focused on the research strategy from chemical markers to Q-markers, picked up the characteristics of the Q-markers from the near infrared spectrum (NIRS), and explored the feasibility of establishing the NIRS assay based on Q-marker. After integrated the biological activity detection and artificial neural network algorithm, we try to establish the relationship between the spectral properties of NIRS and specific efficacy of the CMM. Finally, the bottlenecks will be solved that related to the transmission and traceability of quality attributes in the process of TCM production, quantity change, overall quality management and so on. This system is going to improve TCM quantity scientific and intelligent supervision, and promote the upgrading of traditional TCM industry.
To investigate the effect of scutellarin (Scu) on diabetic cardiomyopathy in mice, type 2 diabetes mellitus was induced by intraperitoneal injection of 50 mg·kg-1 streptozotocin (STZ) into a high-fat diet. Scu was injected intraperitoneally. After 8 weeks, fasting blood glucose and serum biochemical parameters were measured. Masson staining was performed on myocardial tissue. The expression levels of Nrf2, NFκB, AKT and p-AKT in myocardium of mice were observed by Western blot. All the procedures were approved by the Laboratory Animal Ethics Committee of the Peking Union Medical College. The results showed that Scu significantly decreased the heart-body ratio, increased myocardial contractile function, decreased the level of myocardial fibrosis and the expression of collagen I and collagen Ⅲ in myocardium of diabetic mice. Scu can effectively reduce the levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB), malondialdehyde (MDA) in serum of diabetic mice, increase the level of antioxidant enzymes in serum, and inhibit the release of inflammatory factors. Further studies showed that Scu significantly increased Nrf2 nuclear translocation, inhibited NFκB nuclear translocation and increased AKT phosphorylation. It indicates that Scu has significant effect on diabetic cardiomyopathy in mice.