Oxygen is an essential element for life, which is mostly consumed at mitochondria for energy metabolism. For the genome inside nucleus, oxygen conducts structural regulations and chemical modifications through multiple pathways, where reactive oxygen species (ROS) serve as important messenger molecules. The highly activated ROS have the ability to produce different kinds of DNA lesions, while ferrous ions provide supports in many forms. Under the combinatorial action of oxygen and iron, almost all the genomic biochemical processes, such as replication, transcription and DNA damage repair are affected. Moreover, the variation of environmental oxygen concentration, particularly hypoxia that presents in many major diseases and critical physiological stages, provokes the responds at the genomic level. While the factors that lead to these genomic alterations are potential drug targets and deserve systematic investigations, herein, we collect the existing knowledge in the effects of ROS, ferrous ion and cell hypoxia on genome, along with brief discussions of the related drug molecules.

Polyketide synthase 13 (Pks13) performs a critical role in the final assembly step of mycolic acid synthesis in Mycobacterium tuberculosis. The inhibition of Pks13 can influence the biosynthesis of mycolic acid, which leads to Mycobacterium tuberculosis cell death. Researchers have discovered Pks13 inhibitors with five chemical scaffolds as antituberculosis agents. Herein, we summarize recent advances in the study of Pks13 inhibitors including the process of discovery, the mechanism of action and structure-activity relationships.

In recent years, multi-modal combined anti-tumor has become an effective strategy for clinical tumor treatment. Photothermal therapy with its characteristics of minimally invasive, controllable, high efficiency, and strong specificity, can effectively make up for the toxic side effects and tumor resistance caused by traditional drug treatment. The research shows that the combination of photothermal therapy and chemotherapy has better synergistic antitumor effect. However, chemotherapeutic drugs and photothermal agents may have different pharmacokinetic behaviors in vivo, so it is difficult to ensure their effective transmission in tumor site, and the free form is easy to be metabolized and degraded in vivo. How to deliver the two therapeutic modes of drugs/photothermal reagents to tumor tissues in a specific, efficient and synchronous manner to achieve the best combined antitumor effect is an important problem to be solved in the combined antitumor application. The development of nano-drug delivery technology provides a new idea for the application of tumor treatment. In this paper, combined with the latest research progress in this field, the anti-tumor mechanism of photothermal therapy combined with chemotherapy, the advantages of nano drug delivery, the types and characteristics of commonly used nano materials and the principle of drug delivery are reviewed in order to provide a reference for the further development of multi-mode combined treatment of tumor.

This study was to determine the expression of the cell cycle inhibitor p21 in alveolar macrophages (AMs) and the role of p21 in activation of AMs in bleomycin (BLM) injury-induced lung fibrosis. The expression of CD206 in AMs was measured by immunofluorescence staining. Reverse transcription-polymerase chain reaction (RT-PCR) assay was used to detect the expression of macrophage activation markers. The coculture assay for macrophage and fibroblast was employed to explore the effect of macrophage on fibroblast activation. Immunofluorescence staining and western blotting assay were adopted to detect the expression of p21 in fibrotic tissues. AMs were treated with p21 knockdown or overexpression virus, RT-PCR and the co-culture system were used to explore the effect of p21 expression on macrophage activation. 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. Our results showed that the expression of CD206 and macrophage activation markers was increased in AMs from fibrotic mice, indicating that AMs from fibrotic mice were associated with a profibrotic phenotype. Moreover, the expression of p21 was upregulated in AMs after BLM treatment. Depletion of p21 suppressed macrophage activation, while overexpression of p21 promoted the profibrotic phenotype of AMs from healthy mice. In summary, BLM injury causes the progressive accumulation of p21 in AMs, which induces the production of a number of profibrotic factors promoting the development of pulmonary fibrosis.

Pharmacological activity and drug likeness depend in principle upon the microscopic structure and macroscopic properties of drugs, which reside in their molecular structures. By means of medicinal chemistry the evolution of an active compound to a novel drug (NME) essentially makes the two pillars coexistence in one chemical structure, which either could merge as an intrinsic structure or connect from external fragments to each other with covalent bonds. Since the new millennium the advance in biology provides several knowledge and technologies, for example humanized monoclonal antibody, proteasome-ubiquitin system, allosteric modulation, natural macromolecules, structural biology, etc., for innovation of novel medicines. Taking several examples on marketed drugs or drug candidates in clinical trials, this article tries to concisely illustrate R & D conception of biology-driven drug design.

Abnormal expression of polycomb repressive complex 2 (PRC2) is related to the development of a variety of diseases. Inhibition of normal or overactive PRC2 can reduce cell survival and inhibit tumor growth in several cancers. Therefore, the identification and development of small molecule inhibitors has become an active field of current epigenetic-related anti-tumor strategies. A small molecule inhibitor targeting the S-adenosyl-L-methionine (SAM) binding site of enhancer of zeste homologue 2 (EZH2) has been approved by FDA. However, acquired drug resistance is of concern. Drugs targeting two different binding sites of embryonic ectoderm development (EED) are also being developed. The development of EZH2-EED proton pump inhibitor has attracted extensive attention due to its unique mechanism of action. In this paper, we review the research progress on various small molecule inhibitors that target PRC2-related proteins to provide a basis for further research and development of related drugs.

N-Acetylaspartate (NAA) is a highly abundant brain metabolite. Nowadays, as an important marker reflecting the function of nervous system, NAA is widely used in the results analysis of nuclear magnetic resonance spectroscopy (¹H MRS). NAA is synthesized in mitochondria of neurons and metabolized in oligodendrocytes. Additionally, NAA may be converted to the dipeptide N-acetylaspartylglutamate (NAAG), and catabolized into NAA and glutamate in astrocytes. NAA is related to a variety of central nervous system diseases, including Canavan disease, multiple sclerosis, depression, schizophrenia and other mental diseases. Therefore, NAA may be a biomarker of these diseases, and its related enzymes may be used as therapeutic targets for drug screening. Here, we combined the current research on the molecular mechanisms of NAA to reveal the process of NAA generation, metabolism and transport in the brain, explain the possible physiological effects of NAA and discuss its relationship with central nervous system diseases, explore the prospect of NAA in disease prediction and diagnosis, as well as the targeted treatment that may become the breakthrough of refractory diseases.

An ethanol extract of Chloranthus henryi (Chloranthaceae) was subjected to various chromatographic procedures including silica gel column chromatography, MCI column chromatography, Sephadex LH-20 column chromatography, and preparative HPLC. Five purified sesquiterpenes analyzed by spectroscopic analyses (MS, IR, NMR) and single crystal X-ray diffraction were elucidated as (1S, 6S, 8R)-8-ethoxychlomultin C (1a), (1R, 6R, 8S)-8-ethoxychlomultin C (1b), (+)-phaeocaulin D (2), atractylenolide Ⅰ (3), and 8-β-ethoxyasterolid (4). Compounds 1a and 1b were a new pair of sesquiterpene enantiomers and compounds 2-4 were isolated from this plant for the first time. Compounds 1a, 1b, 2 and 3 increased cell viability in H₂O₂-treated PC12 cells from (43.41±1.59)% to (61.71±7.56)%, (66.05±5.61)%, (74.34±3.32)% and (69.58±5.02)% at 10 μmol·L^-1, respectively.

In order to explore the use of DNA barcode in the identification of wild Phytolacca resources in the Shaanxi Guanzhong area, 29 DNA samples were amplified and sequenced by using the universal primers ITS2 and psbA-trnH. The sequences were spliced and proof-read by Codon CodeA aligner V3.0, followed by blast comparison and identification analysis; mega 6.0 was used to analyze sequence characteristics, Kimura 2-Parameter (K2P) was used to analyze distance and intraspecific or interspecific variation, and Neighbor-Joining trees were established to evaluate the ability of two pairs of candidate sequences to distinguish Phytolaccae Radix from its adulterants. The results showed that the success rate of PCR amplification and sequencing of ITS2 and psbA-trnH was 100%; the NJ tree showed that both ITS2 and psbA-trnH sequences could separate P. acinosa, P. americana, other species of the same genus like P. japonica, P. exiensis and two adulterant species into a single clade; primer ITS2 had an advantage over psbA-trnH in determining interspecific genetic distances. Therefore, both ITS2 and psbA-trnH sequences can be used for identification of Phytolacca and their adulterants, which provides a theoretical basis for the distribution of wild Phytolacca resources and their rational development and utilization.

Ethylene-response factors, which are a subfamily of the AP2/ERF family, play an important role in ethylene signal transduction, plant growth and plant resistant. In this study, a full-length cDNA of the AsERF1 gene was cloned from Aquilaria sinensis. Sequence analysis, prokaryotic expression and purification, subcellular localization, tissue-specific analysis and expression analysis under different abiotic stresses was performed. The open reading frame (ORF) of the AsERF1 gene was 691 bp, encoding a protein of 229 amino acids with a predicted molecular mass of 25.36 kD. The AsERF1 protein contained the conserved AP2 sequence of ERF protein. A phylogenetic analysis indicated that the AsERF1 protein showed greatest sequence similarity with ERF2 from Populus trichocarpa. The recombinant AsERF1 protein was expressed in Escherichia coli BL21(DE3) cells using the prokaryotic expression vector pET28a-AsERF1 and the recombinant AsERF1 protein was purified. Agrobacterium-mediated protein expression experiments demonstrated that AsERF1 mainly localized to the nucleus. Expression analysis indicated that AsERF1 was primarily observed in leaves. The AsERF1 expression level was induced by salt, drought, low temperature and CdCl₂ treatment, while the abundance of AsERF1 was most significantly induced by drought stress. These results provide valuable insights into the role of AsERF1 in plant defense and the mechanism of agarwood formation.