Latest ArticlesType 2 diabetes is a common form of diabetes and can have serious consequences for diabetics when their wounds do not heal properly due to impaired function. Glycosaminoglycans (GAGs) are widely found in skin tissue. Due to the isomerization of C6 in uronic acid and different sulfuric acid substitutions, the structure of GAGs is relatively complex. The fine structure of GAGs in the skin of diabetic patients has not been studied. In this study, the structure of GAGs in the skin of streptozotocin (STZ)-induced diabetic mice was characterized by liquid chromatographytandem mass spectrometry (LC-MS/MS). All animal experiments were carried out with approval of the Animal Ethics Committee of Ocean University of China. The results indicate that the content of hyaluronic acid (HA) in STZ-induced diabetic mouse skin was significantly lower than that of non-diabetic mice. Although there was no significant difference in the content of chondroitin sulfate (CS) and heparin sulfate (HS) between diabetic mouse and normal mouse skin, the disaccharide compositions were different. The expression of CS-4S6S, HS-0S, HS-NS, and HS-6S in STZ-induced diabetic mouse skin was higher than in non-diabetic mice. While the content of HS-NS6S was lower. In addition, the degree of sulfation of HS in STZ-induced mouse skin was lower than that of normal mouse skin. These results provide a basis for the pathogenesis of diabetes and the development of wound healing dressings for diabetic patients.
The structural modification of natural product represents a powerful tool for anti-cancer drug discovery. Noscapine, as a phthalideisoquinoline alkaloid from opium, has been used as an over-the-counter antitussive drug with excellent oral bioavailability and low toxicity. Recently, the potential of this compound as a particularly attractive lead for anti-cancer drug discovery has been demonstrated. Multiple mechanisms, especially the interference of tubulin polymerization, might be involved. Thereafter, various structural modifications based on semisynthetic routes, which aims to improve the anti-cancer activity and pharmacokinetic properties, as well as to probe the mechanism, has been performed. Several analogues are emerging as possible candidates as novel anticancer therapies. This perspective mainly discusses the advancing noscapine and related analogues in the fight against malignant disease in recent years. Furthermore, the future directions of this evolving field were also preliminary prospected.
Blocking the binding of programmed death 1 (PD-1) on the T cells and programmed death ligand 1 (PD-L1) on the tumor cells has become a hotspot in the field of tumor immunotherapy. Small-molecule checkpoint inhibitor targeting PD-1/PD-L1 axis is the new direction of tumor immunotherapy. In the present study, we investigated the anti-tumor role of hyperoside by regulating the PD-L1 level in non-small cell lung cancer (NSCLC). Changes of total PD-L1 and membrane PD-L1 levels were determined by Western blot, flow cytometry, and PD-1/PD-L1 interaction assays. The expression of mRNA level of PD-L1 was detected by real-time PCR. The cytotoxicity of activated human T cells toward co-cultured tumor cells was measured by cell impedance assay and crystal violet experiment. The antitumor effect of hyperoside in vivo was examined by C57BL/6 mice bearing Lewis xenograft tumor. Western blot and flow cytometry assay showed that hyperoside significantly downregulated the abundance of PD-L1 in H1975 and HCC827 cells in dose- and time-dependent manner. PD-1/PD-L1 binding assay revealed that hyperoside reduced the binding of tumor cells to recombinant PD-1 protein. In addition, hyperoside decreased the abundance of c-Myc, a key transcriptional regulator of PD-L1, in H1975 and HCC827 cells. Cell impedance and crystal violet staining indicated that hyperoside enhanced the killing activity of co-cultured T cells toward tumor cells. Animal experiments (all animal experiments were conducted in accordance with the Animal Ethics Committee of the Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences) revealed that hyperoside treatment displayed significant suppression in the growth of Lewis tumor xenografts in C57BL/6 mice with an inhibition rate of 48.3% at 25 mg·kg-1. Our results demonstrate that hyperoside exerts its anti-NSCLC activity by reducing the PD-L1 level. Our study provides an important material basis and scientific basis for developing hyperoside into a new small molecule drug for tumor immunotherapy.
In recent years, the prevalence of non-alcoholic fatty liver disease (NAFLD) has been dramatically increased in China and specific targeted therapy is still unavailable. The purpose of this research was to investigate whether schisandrin B (SchB) improves NAFLD and the potential mechanisms. Wildtype mice with C57BL/6J background were treated with special high fat diet (containing 40% fat, 22% fructose, 10% sucrose, and 2% cholesterol) for 16 weeks to induce NAFLD. Then SchB (120 mg·kg-1) were used to treat NAFLD mice for 6 weeks. Body weight, food intake, glucose tolerance, insulin resistance, serum level of total cholesterol (TC), triglycerides (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were assayed and histopathological analysis were performed to evaluate the improvement of NAFLD induced by SchB. Furthermore, the level of lipopolysaccharide (LPS) in serum, intestinal permeability, and the expression of genes and proteins associated with mucosal defense were evaluated, intestinal flora composition in fresh cecal contents were analyzed and differential flora were identified to explore the potential mechanism. All animal experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. These results showed that SchB significantly reduced the body weight of NAFLD mice without changing food intake, and effectively reduced serum level of TC, ALT, and AST. SchB also significantly altered the composition of the microflora in NAFLD mice, increased the abundance of the Akkermansia muciniphila (A. Muciniphila) and elevated the expression of genes and proteins associated with the mucosal defense in ileum and colon, restored the permeability of intestinal barrier. In summary, SchB improves NAFLD by regulating the composition of the microflora and enhancing the function of intestinal barrier to further reduce the excessive lipids accumulation and hepatic inflammation.
Cancer is a malignant disease threatening human health and life. Early diagnosis of carcinoma plays an important role in the treatment of carcinoma, so tumor imaging agents have been the focus of research in this field. Mannose receptor is a C-type lectin receptor, which expressed in various tumor tissues, sentinel lymph nodes and has become an important tumor marker. In recent years, a variety of imaging agents targeting mannose receptors have been designed and developed. This review summarizes the representative achievements.
Bacterial pneumonia is a common clinical disease and the abuse of antibacterial leads to the production and prevalence of resistant bacteria. Novel antibacterial active ingredients can be found from natural products for the treatment of bacterial pneumonia. Pulmonary delivery systems can directly deliver drugs to infected lung tissues, favoring the treatment of bacterial pneumonia. Cinnamon oil (CO) is a volatile oil extracted from cinnamon, which has antibacterial and anti-inflammation functions. However, the preparation of its pulmonary delivery systems is difficult because of its oil and volatile properties. Here, CO-β-cyclodextrin inclusion complex (CO-β-CD) was prepared. Its dry powder inhalers (DPIs) were obtained by lyophilization. The DPIs had the aerodynamic diameter of 1.34 μm and the fine particle fraction (FPF) of 30.90%, which was suitable for pulmonary delivery. The minimal bactericidal concentration of CO-β-CD was 2 mg·mL-1 against Staphylococcus aureus (SA). The animal experiments were approved by the Ethics Committee of Academy of Military Medical Sciences and the experiments were conducted in accordance with relevant guidelines and regulations. A high intratracheal (i.t.) dose (100 mg·kg-1) of CO-β-CD did not show significant toxicity to the mice. Bacterial pneumonia mice models were established after intraperitoneal injection of dexamethasone and then i.t. administration of SA. CO-β-CD and penicillin were separately i.t. administered to the mice. Both of them alleviated the lung injury of mice and remarkably increased the survival rates. Compared to penicillin, CO-β-CD significantly reduced the infiltration of inflammatory cells and the numbers of leukocytes and neutrophils in the blood, and the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the lung tissues were similar to those of the healthy mice, indicating that CO-β-CD had the capability of anti-inflammation besides antibacterial effect in vivo. CO-β-CD dry powder inhalers are a potential pulmonary delivery system for the treatment of bacterial pneumonia.
High altitude pulmonary edema (HAPE) is a result of leaking of the fluids from blood vessel to the lung tissue due to pulmonary artery hypertension in the high altitude place, which happens very quickly and shows high mortality. Sildenafil (SIL) can prevent HAPE by expanding pulmonary vessels; however, only oral tablets and injections of SIL are currently available. The formulations have the disadvantages of high doses, inconvenient use, and high systemic side effects. Here, liposomal sildenafil (LS) was prepared for pulmonary delivery and the prevention of HAPE was explored. The ammonium sulfate gradient method was used for the preparation of LS with a high entrapment efficiency of nearly 100%, the particle size of 116.97 nm, and the zeta potential of -30.93 mV. All animal experiments had been approved by the Ethics Committee of Academy of Military Medicine, Academy of Military Sciences, and carried out in accordance with relevant guidelines and regulations. The dose (3 mg·kg-1 SIL) of sildenafil suspensions, LS or blank liposomes was intragastrically or intratracheally administered to the lungs of mice. The mice with or without treatment were put in the hypobaric oxygen chamber of 5 000 m altitude for 1 h. In the open field text the model mice had the shorter total distances and longer dead time than the healthy mice and they showed the lower percutaneous oxygen saturation (SpO2), the higher tumor necrosis factor-α (TNF-α) levels of and the lower reduced glutathione (GSH) in the lung tissues. By contrast, oral LS remarkably modified the moving ability of the mice and they had the higher SpO2 than the model mice and the similar TNF-α and GSH levels to the healthy mice. Sildenafil suspensions and LS with the same dose (3 mg·kg-1 SIL) were intratracheally administered to mouse lungs, respectively, and the mice of the model group and the treatment groups were put in a hypobaric oxygen chamber for predetermined time. In the rotating rod experiments, the mice in the model group showed shorter drop latency and more drop times than those in the healthy group, indicating that the physical activity of the mice was improved due to treatment. The inflammatory cytokines, TNF-α and interleukin-1β (IL-1β) in the blood of model mice were higher than those from the healthy group and they decreased after treatment, where the LS group maintained the lowest level close to the normal level. IL-1β in the blood of mice in the LS group was lower than that in the SIL group (P < 0.05) 1 hour and 48 hours post-hypoxia. Hypoxia inducible factor-1α (HIF-1α) in the lung tissues of model mice increased but decreased to the normal range after treatment. Moreover, HIF-1α in the LS group was lower than that in the SIL group, where the values were significantly different 48 hours post-hypoxia (P < 0.01). Inhaled liposomal sildenafil is a promising medication for the prevention of HAPE.
Most small molecule drugs bind to enzymes, receptors or ion channels, which possess binding pocket for drug occupation. However, the study of drugs that interfere with protein-protein interactions has always been a challenging subject. The discovery of molecular glues and degraders has opened an avenue to tackle this issue. With the structural features of bifunctional ligand molecular glues mediate the recognition and binding of two proteins. As a useful tool for chemical biology molecular glue can not only help to find probes to undruggable targets, but also can be developed into drugs through structure optimization in medicinal chemistry. This minireview concisely describes the features of molecular glue using a few existing drugs or active compounds.
Transient receptor potential vanilloid ion channel subtypes 2 (TRPV2) is a calcium permeable nonselective cation channel. TRPV2 is expressed in nerves, blood vessels, spleen, and other organs, and participates in the regulation of a variety of important physiological functions, such as nociception, neural development, and immune response. Here we reviewed the research progress on the structure, modulators, and physiological functions of TRPV2 channel to provide references for future research.
Hypoxia is one of the most significant characteristics of solid tumors. Hypoxia microenvironment can lead to the overexpression of hypoxia inducible factor-1α (HIF-1α). As the most critical transcription factor in the hypoxia response, HIF-1α activates downstream gene expression resulting in abnormal tumor cell proliferation, tumor angiogenesis, unusual energy metabolism, increased drug resistance, invasion, and metastasis. Down-regulation of HIF-1α expression is considered as a promising approach for the treatment of solid tumors, whereas the clinical efficacy of most existing HIF-1α inhibitors is restricted in low efficacy and high toxicity. Therefore, it is particularly important to develop powerful and safe novel drugs against the overexpression of HIF-1α. In recent years, numbers of studies have proved that a variety of chemical components of traditional Chinese medicine can directly or indirectly inhibit the activation of HIF-1α, which has a broad prospect in the fight against hypoxia-induced tumor progression. In this review, we summarized various anti-tumor active components of traditional Chinese medicines responsible for inhibiting the expression of HIF-1α in last ten years and analyzed the corresponding mechanism, with a view to further research as a reference.