Diabetic ulcer is recognized as a chronic nonhealing wound, often associated with bacterial infection and tissue necrosis, which seriously affect patients' health and quality of life. The traditional treatment methods exist some problems, such as bacterial resistance and secondary trauma, so it is urgent to find new methods to meet the requirements of diabetic ulcer treatment. In this study, we prepared a drug delivery system (DFO@CuS nanoparticles) based on hollow copper sulfide (CuS) nanoparticles loaded with deferoxamine (DFO), which realized the synergistic therapy of promoting angiogenesis and photothermal antibacterial. The morphological structure and particle size distribution of DFO@CuS nanoparticles were characterized by transmission electron microscopy and particle size analyzer, respectively. The antibacterial effect of DFO@CuS nanoparticles was evaluated by the plate coating method. The effects of DFO@CuS nanoparticles on the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) were evaluated by CCK-8 (cell counting kit-8) assay, cell scratch assay, and tube formation assay. The results showed that DFO@CuS nanoparticles were hollow and spherical in shape with an average particle size of (200.9 ±8.6) nm. DFO@CuS nanoparticles could effectively inhibit the growth of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PA) under near-infrared (NIR) light irradiation. DFO@CuS nanoparticles showed negligible cytotoxicity and effective acceleration of cell migration and tube formation in a certain concentration range. In conclusion, the prepared DFO@CuS nanoparticles exhibit good photothermal antibacterial properties and pro-angiogenic effects, providing a basis for their application in the treatment of diabetic ulcer.

Total flavonoids of Dracocephalum moldavica L. (TFDM) is an effective component extracted and isolated from the traditional Uighur medicinal herb Cymbidium fragrans. Cymbidium fragrans has the effects of tonifying the heart and brain, promoting blood circulation and resolving blood stasis, and has been widely used in the treatment of cardiovascular and cerebrovascular diseases for a long time. The purpose of this study was to determine the effect of total flavonoids from Cymbidium fragrans on hypoxia/re-oxygenation (H/R) injury in H9c2 (rat cardiomyocytes) cells and its mechanism. A model (H/R) of hypoxia/re-oxygenation injury in H9c2 cells was established using hypoxia and glucose deprivation for 9 h combined with re-oxygenation and rehydration for 2 h to simulate myocardial ischemia-reperfusion injury. The effects of total flavonoids from Cymbidium fragrans on cell viability, markers of myocardial cell damage, oxidative stress levels, and reactive oxygen radical (ROS) content were investigated, Western blot was used to detect the expression of vascular endothelial growth factor B (VEGF-B) and adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway related proteins. The results showed that the total flavonoids of Cymbidium fragrans significantly increased the viability of myocardial cells after H/R injury, and decreased the content of lactate dehydrogenase (LDH) and creatine kinase isozyme (CK-MB) in the cell supernatant. It significantly reduced malondialdehyde (MDA), increased superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities, and decreased intracellular ROS and nitric oxide (NO) content. Western blot analysis showed that the total flavonoids of Cymbidium fragrans decreased Bax levels in H9c2 cells damaged by H/R and increased Bcl-2 expression. Total flavones of Cymbidium fragrans upregulate VEGF-B/AMPK pathway related proteins VEGF-B, vascular endothelial growth factor receptor 1 (VEGFR-1), neuropilin 1 (NRP-1), peroxisome-proliferator-activated receptor γ coactivator-1α (PGC-1α), phosphorylated adenosine monophosphate activated protein (p-AMPK) and phospho mechanistic target of rapamycin (p-MTOR) levels. The above research results indicate that the total flavonoids of Cymbidium can significantly reduce the H/R injury of myocardial cells, which may be related to the upregulation of VEGF-B/AMPK pathway and inhibition of oxidative stress response.

Asparaginyl endopeptidases (AEPs) in plants belong to the family of cysteine protease that undergo self-activation in the form of zymogen in acidic vacuole and play important physiological roles in maturation of seed storage proteins, protein degradation, programmed cell death and host defense. Bioprocessing enzymes (peptidyl Asx-specific ligases, PALs) that promote the maturation of cyclotides have recently been isolated and identified from several cyclotide-rich plants. PALs derived from AEPs can site-specifically catalyze the formation of asparagine or aspartate peptide bonds. Due to the advantages of relatively traceless peptide bonds and broad substrate spectrum and high catalytic efficiency, they have been playing important roles in the cyclization and modification of peptides and proteins, and are powerful tools for improving the stability of peptide drugs. This review describes the physiological functions of AEPs in plants and summarizes the discoveries, structural characteristics, catalytic mechanism and protein engineering of PALs, as well as the limitation of their applications and future trends. In addition, the applications of PALs in cyclotides biosynthesis and the development of macrocyclic peptides are highlighted, with the aim of providing a new idea for the biocatalytic synthesis of cyclic peptides.

UiO-66 (University of Oslo 66) is a kind of promising material that can improve the release and bioavailability of poorly water-soluble bioactive compounds of traditional Chinese medicine. However, the loading of quercetin in raw UiO-66 was not ideal. In this study, UiO-66-BH (UiO-66-blend-heating) was obtained by heating UiO-66 and KOH solution following blended them. UiO-66-BH maintained the outline of octahedral structure of UiO-66 but with obvious rough and uneven pores on the surface. UiO-66-BH had good adsorption of quercetin with saturation adsorption was 138.92 mg·g^-1, the adsorption process belonged to single molecular layer adsorption and was controlled by chemisorption. UiO-66-BH can control the release of quercetin in simulated gastrointestinal fluid, and the drug concentration was significantly higher than that of free quercetin after long-term release (36% vs 9%). Compared with quercetin, the ABTS (2, 2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) ammonium salt) radical scavenging activity of UiO-66-BH@quercetin drug delivery system decreased, while the DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging activity remained almost unchanged. The drug delivery system showed a strong antioxidant effect similar to quercetin. The findings indicated that UiO-66-BH could control release of quercetin and was expected to be used as a drug carrier material for some insoluble active components of traditional Chinese medicine such as quercetin.

As an important component of nucleosomes on the chromatin of eukaryotic cells, histones play an important role in the development and progression of tumour diseases by regulating epigenetic post-translational modifications such as acetylation and methylation. In addition, development of inhibitors targeting methyltransferase and deacetylase provides novel therapeutic strategies for cancer treatment. Mass spectrometry-based proteomics can reveal the global changes of histone modifications under the action of drugs during disease progression, which in turn provides important support for revealing drug action mechanism, drug resistance mechanism, and investigating novel drug combination strategies. This article focuses on the progress and status of proteomic research on a variety of histone modifying enzyme inhibitors, including methyltransferase inhibitors and histone deacetylase inhibitors, which will help to understand the current and further utilization of proteomics in studying histone modifications.

Autophagy is an important physiological process that can degrade cell components and maintain cell homeostasis, divided into three types including macroautophagy, microautophagy and chaperon-mediated autophagy generally, and macroautophagy is the most common form. Autophagy can affect the progression of a variety of diseases, such as cancer, neurodegenerative diseases, heart-related diseases, and autoimmune diseases, etc. However, autophagy can promote or inhibit diseases in different circumstances because of the dual roles of autophagy. Therefore, targeted regulating autophagy may be a potential treatment plan for diseases in specific stages of disease development. Now, with the development of traditional Chinese medicine (TCM) resources and the deepening of researches on the modern utilization of TCM, many active compounds from TCM have been discovered that can target autophagy to exert pharmacological activity. Most of the natural compounds activate or inhibit autophagy by affecting the classical PI3K/AKT/mTOR autophagy pathway. In addition, some compounds can also affect autophagy through MAPKs signaling pathways such as MEK/ERK, JNK and p38MAPK. These active compounds exert various biological activities by regulating autophagy, including anti-tumor, inhibiting neurodegenerative diseases, protecting cardiomyocytes, and relief of inflammatory response. In this review, we summarized the active compounds in TCM that affect autophagy by targeting different signaling pathways and their mechanisms of regulating autophagy, also introduced the effects of active compounds on diseases after affecting autophagy. Finally, this paper summarized and prospected the development of targeted autophagy for the treatment of diseases by TCM compounds, hoping to provide clues for subsequent exploration and research.

This study investigated the protective effect of chrysin on hepatic fibrosis by regulating AMP-activated kinase (AMPK)-NOD-like receptor protein 3 (NLRP3) mediated pyroptosis pathway. The hepatic fibrosis model of mice was established by thioacetamide (TAA) in vivo. Except the control and chrysin alone groups, the mice were injected intraperitoneally with TAA at 100 mg·kg^-1, three times per week for the first week. From the 2^nd to 5^th week, mice were injected intraperitoneally with TAA at 200 mg·kg^-1, three times per week for the next 4 weeks. Chrysin groups were intragastrically administrated once per day to 5^th week. The histopathological changes were detected by HE and Masson staining. The levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were assessed by the kits. All animal experiments were approved by the Medical Ethics Committee of Affiliated Zhongshan Hospital of Dalian University (DWLL2019060). LX-2 cells were stimulated by (transforming growth factor-β, TGF-β) in vitro. The protein expressions of AMPKα, p-AMPKα, NLRP3, cysteinyl aspartate specific proteinase-1 (caspase-1), gasdermin D (GSDMD) were detected by Western blot, and the mRNA levels of collagen-Ι, α-smooth muscle actin (α-SMA), interleukin-1β (IL-1β), IL-18, caspase-1, GSDMD were analysis by reverse transcription-polymerase chain reaction (RT-PCR). Chrysin attenuated the increases in serum AST and ALT levels in the TAA group, while significantly improved the changes of liver morphology, reduced liver tissue inflammatory cell infiltration and inhibited collagens deposition. Compared with TAA group, chrysin effectively activated AMPKα phosphorylation and inhibited hepatic NLRP3 inflammasome activation. Additionally, the protein expressions and mRNA levels of IL-1β, IL-18, caspase-1 and GSDMD in chrysin groups were decreased. Chrysin inhibited the expressions of collagen-Ι and α-SMA, enhanced the phosphorylation of AMPKα, and decreased the expressions of NLRP3 and GSDMD. Therefore, chrysin may inhibit inflammatory injury and pyroptosis possibly by activating AMPK and inhibiting NLRP3 inflammasome to alleviate hepatic fibrosis.

Attenuated Salmonella typhimurium VNP20009 is a widely used natural oncolytic bacterium, which has great application potential given its unique characteristics, including clinical safety, tumor targeting specificity, and explicit genome sequence. Here, we show that tumor progression can be effectively reduced by intraperitoneal administration with VNP20009 in a mouse model of melanoma (all animal experiments were conducted in accordance with the Animal Ethics Committee of China Pharmaceutical University); co-culture experiment in vitro demonstrated that VNP20009 can induce the polarization of macrophage M1, accompanied by expression of inflammation-related factors; flow cytometry analysis showed that VNP20009 induced the increase of immune cell infiltration in tumor. Further analysis showed that T cells infiltration in tumor-draining lymph node (TDLN) increased, and VNP20009 induced the activation of CD4⁺ T cells and CD8⁺ T cells in tumor. Our results demonstrate that VNP20009 treatment significantly inhibited melanoma tumors by remodeling tumor-associated macrophages to an M1-like phenotype, as well as recruiting and activating cytotoxic T cells, combined with its own antigenic activity to exert anti-tumor immunity.

α-Conotoxin ArIB[V11L,V16D] is currently the most optimal selective inhibitor of α7 nicotinic acetylcholine receptor (nAChR) known. In order to explore chemical modification methods and enrich its application in targeting nAChR, this study utilized the linker to covalently connect camptothecin and 7-amino-4-methylcoumarin to the [2,4] disulfide bond of ArIB[V11L,V16D]. Therefore, two peptide-drug conjugates (PDCs), ArIB[V11L,V16D]-5 and ArIB[V11L,V16D]-6, and one fluorescent-labeled peptide, ArIB[V11L,V16D]-7 were constructed. Cytotoxicity evaluation showed that the IC₅₀ values against non-small cell lung cancer cell line A549 of the two PDCs were respectively 1.3 and 4.1 times of camptothecin, indicating slight reduction in activity at the cellular level which was related to the linker structure. Fluorescence spectrum scanning revealed that the excitation and emission wavelength of the fluorescent-labeled peptide were 340 nm and 403 nm respectively, and the fluorescence features of 7-amino-4-methylcoumarin as a marker were retained without fluorescence quenching. This modification strategy laid a solid foundation for the further application of α-conotoxin ArIB[V11L,V16D] in PDCs and fluorescent probes.

Bacterial biofilm widely exists in all kinds of bacteria, and is related to about 80 percent of bacterial infections. It is one of the main reasons for bacterial tolerance and resistance to existing antibiotics. Therefore, there is unmet clinical need for new anti-biofilm drugs. At present, there are three kinds of anti-biofilm agents under research, including biofilm inhibitors, biofilm dispersal agents and biofilm eradication agents. Among them, the biofilm eradication agent is unique, which can not only kill bacteria in biofilm but also eliminate biofilm as a monotherapy. Based on modifications of natural products with antibacterial activity, a variety of compounds with biofilm eradicating activities have been obtained, such as, acyldepsipeptides, pyrrolomycins, halogenated phenazines and halogenated 8-hydroxyquinolines. In this review, we summarize several major biofilm eradication agents above according to their structures and mechanisms.