Strategy of eudragit coated curcumin nanoparticles delivery system: Release and cell imaging studies in simulated gastrointestinal microenvironments.

Curcumin has a broad-spectrum anti-tumor effect and has no toxic side effects. However, the unique diketone structure of curcumin will undergo diketo-enol tautomerism under different acid-base conditions, resulting in its instability under physiological conditions. In addition, the low biocompatibility and absorption rate of curcumin also limit the use of curcumin drugs. In this paper, curcumin was modified by substitution of acryloyl and acrylsulfonyl groups, and four kinds of nanoparticles with regular morphology were prepared using non-toxic and non-irritating acrylic resin as coating material to improve the stability and bioavailability of the compounds. Zeta potential testing shows that the composites surface carries positive charges and have good stability. In the release experiment, four complexes have the potential for slow and controlled release. Imaging of Hela cells with different channels was performed, and the imaging results showed that the complexes could enter the cells and be absorbed by them, demonstrating good imaging performance. MTT experiments have shown that the complexes have certain anti-tumor activity and low cytotoxicity. In general, the complexes synthesized in this paper have potential in the field of drug fluorescence imaging detection. At the same time, this experiment provides a new idea for the design of slow and controlled release of drugs.

A novel strategy to bind pyrimidine sulfonamide derivatives with odd even chains: exploration of their design, synthesis and biological activity evaluation.

Based on the hybridization strategy of dominant fragments, a series of pyrimidine sulfonamide (PS) derivatives were obtained by combining the pharmacophore fragments (sulfonamide group and pyrimidine group) with different biological activities, and evaluated as a new type of anticancer drug. The compounds were evaluated for in vitro cytotoxicity against four human cancer cell lines (HeLa, HCT-116, A-549 and HepG2) and the normal human cell line L02. Compared with the anti-cancer drug 5-fluorouracil (5-FU), the antiproliferative activity of compound PS14 was close to 5-FU and it has good antitumor activity. The IC50 values were 15.13 ± 2.20, 19.87 ± 2.01, 12.64 ± 3.22, 22.20 ± 1.34 and 102.46 ± 2.27 µM, respectively. The structure activity relationship was analyzed. The antitumor activity of the compound tended to increase. When the substituents of the branch chain of sulfonamides were odd. In addition, the oil-water partition coefficient was also investigated. The logP value of PS14 was between 0 and 3, indicating that PS14 was a compound with good lipophilic property, poor water solubility and easy to be absorbed and transported through cell membrane. The anti-cancer mechanism was further studied by flow cytometry. After PS14 treated HeLa, HCT-116, A-549 and HepG2, the percentage of apoptotic cells was 45.30%, 28.2%, 31.00% and 35.20%, respectively, which was higher than that of the control 5-FU. The results of cell cycle showed that PRD2 mainly blocked the cell cycle in the S phase, thereby inhibiting cell proliferation. Furthermore, molecular docking analyzed possible interactions between the compound and the PI3Kα active site, this compound has good binding with PI3Kα. Overall, this study laid the groundwork for the development and structural modification of new pyrimidine sulfonamide drugs, and PS14 could be further developed into a cancer treatment drug.

A multiple acetal chalcone-BODIPY-based fluorescence: synthesis, physical property, and biological studies.

Fluorescent probes with outstanding physical and biological properties are superior for functional fluorescent dyes design. However, few studies pay attention to the stability of specific groups in fluorescent probes. The aldehyde group in the fluorescent probe is highly active but unstable under certain conditions. Therefore, we introduced ethoxy groups to realize the conversion to aldehyde groups under acidic conditions and avoid the instability of straightforward aldehyde groups. In this work, two fluorophores based on the multi acetal difluoroboraindacene (BODIPY) units with combination of the pharmaceutical intermediate chalcone have been firstly developed. In the design part, chalcone was introduced as a medium for fluorophore and multiple acetal. The mild synthesis strategy is based on the ligand ((Z)-2-chloro-1-(difluoroboranyl)-5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)(phenyl)methyl)-1H-pyrrole) and connects with chalcone in (2E,2'E)-3,3'-(1,3-phenylene)bis(1-(2,4-bis(2,2-diethoxyethoxy)phenyl)prop-2-en-1-one). The emission wavelengths of the products are around 530 nm with high fluorescence intensity. To highlight the biological characteristics of these novel BODIPY fluorescents, we further demonstrated biological analysis studies on MTT and flow cytometry assays. The IC50 values of BODIPY 5 ranged from 79 ± 6.11 to 63 ± 5.67 µM and BODIPY 6 were found to be 86 ± 4.07 to 58 ± 10.51 µM in tested cell lines. Flow cytometry data analysis shows that the representative agent 6 and reference have similar rational apoptosis rates in first quadrant. Last but not least, 6 shows outstanding biological compatibility and cell imaging potential in live cell imaging and in vivo assay, not only is the fluorescence prominent enough, but also rapidly distributes. Thus, our study reports a mild synthesis strategy and full biological analysis on BODIPY fluorescents, and the subtle modulation of the physical and biological properties by pharmaceutical substituents makes these designed chalcone-BODIPY-based dyes hopeful to realize drug functional fluorescent dyes. Two new highly sensitive BODIPY fluorophores are synthesized based on the ligand ((Z)-2-chloro-1-(difluoroboranyl)-5-((4-ethyl-3,5-dimethyl-2H-pyrrol-2-ylidene)(phenyl)methyl)-1H-pyrrole), which connects with chalcone in (2E,2'E)-3,3'-(1,3/4-phenylene)bis(1-(2,4-bis(2,2-diethoxyethoxy)phenyl)prop-2-en-1-one). Multiple acetals were introduced and the physical and biological properties of BODIPYs are described with MTT assay and in vitro and in vivo imaging.

Ferritinophagy-Mediated ROS Production Contributed to Proliferation Inhibition, Apoptosis, and Ferroptosis Induction in Action of Mechanism of 2-Pyridylhydrazone Dithiocarbamate Acetate.

Reactive oxygen species (ROS) production is involved in the mechanism of action of a number of drugs, but the biological effects of ROS remain to be clarified. Furthermore, ferroptosis involves iron-dependent ROS production that may be derived from ferritinophagy; however, the association between ferroptosis and ferritinophagy has not been fully established. The present study demonstrated that dithiocarbamate derivatives (iron chelators) exhibited antineoplastic properties involving ferritinophagy induction, but whether the underlying mechanisms involved ferroptosis was unknown. To gain insight into the underlying mechanism, a dithiocarbamate derivative, 2-pyridylhydrazone dithiocarbamate s-acetic acid (PdtaA), was prepared. An MTT assay demonstrated that PdtaA inhibited proliferation involving ROS production (IC50 = 23.0 ± 1.5 µM for HepG2 cells). A preliminary mechanistic study revealed that PdtaA induced both apoptosis and cell cycle arrest. Notably, PdtaA also induced ferroptosis via downregulation of GPx4 and xCT, which was first reported for a dithiocarbamate derivative. Moreover, these cellular events were associated with ROS production. To explore the origin of ROS, expression of the ferritinophagy-related genes, ferritin, and nuclear receptor coactivator (NCOA4) were measured. Immunofluorescence and western blotting analysis indicated that PdtaA-induced ferritinophagy may contribute to ROS production. To investigate the role of ferritinophagy, autophagy inhibitor 3-methyladenin or genetic knockdown of NCOA4 was employed to inhibit ferritinophagy, which significantly neutralized the action of PdtaA in both apoptosis and ferroptosis. Taken together, PdtaA-induced cell cycle arrest, apoptosis, and ferroptosis were associated with ferritinophagy.

The vicious cycle between ferritinophagy and ROS production triggered EMT inhibition of gastric cancer cells was through p53/AKT/mTor pathway.

Cancer metastasis and resistance for chemotherapeutic agent correlate with epithelial-mesenchymal transition (EMT), while ROS production also involves in the EMT process, However, how autophagy mediated ROS production affects EMT remains unclear. Previous study showed that DpdtC (2,2'-di-pyridylketone hydrazone dithiocarbamate) could induce ferritinophagy in HepG2 cell. To insight into more details that how ferritinophagy affects cellular feature, the SGC-7901and BGC-823 gastric cancer cell lines were used. Interestingly DpdtC treatment resulted in EMT inhibition and was ROS dependent. Similar situation occurred in TGF-ß1 induced EMT model, supporting that DpdtC was able to inhibit EMT. Next the ability of DpdtC in ferritinophagy induction was further evaluated. As expected, DpdtC induced ferritinophagy in the absence and presence of TGF-ß1. The correlation analysis revealed that an enhanced ferritinophagic flux contributed to the EMT inhibition. In addition, ferritinophagy triggers Fenton reaction, resulting in ROS production which give rise of p53 response, thus the role of p53 was further investigated. DpdtC treatment resulted in upregulation of p53, but, the addition of p53 inhibitor, PFT-α could significantly neutralize the action of DpdtC on ferritinophagy induction and EMT inhibition. Furthermore, autophagy inhibitors or NAC could counteract the action of DpdtC, indicating that ferrtinophagy-mediated ROS played an important role in the cellular events. In addition to upregulation of p53, its down-stream targets, AKT/mTor were also downregulated, supporting that DpdtC induced EMT inhibition was achieved through ferritinophagy-ROS vicious cycle mediated p53/AKT/mTor pathway. And the activation of ferritinophagic flux was the dominant driving force in action of DpdtC in gastric cancer cells.

DpdtC-Induced EMT Inhibition in MGC-803 Cells Was Partly through Ferritinophagy-Mediated ROS/p53 Pathway.

Epithelial-mesenchymal transition (EMT) is a cellular process in which epithelial cells are partially transformed into stromal cells, which endows the polarized epithelium cells more invasive feature and contributes cancer metastasis and drug resistance. Ferritinophagy is an event of ferritin degradation in lysosomes, which contributes Fenton-mediated ROS production. In addition, some studies have shown that ROS participates in EMT process, but the effect of ROS stemmed from ferritin degradation on EMT has not been fully established. A novel iron chelator, DpdtC (2,2'-di-pyridylketone dithiocarbamate), which could induce ferritinophagy in HepG2 cell in our previous study, was used to investigate its effect on EMT in gastric cancer cells. The proliferation assay showed that DpdtC treatment resulted in growth inhibition and morphologic alteration in MGC-803 cell (IC50 = 3.1 ± 0.3 µM), and its action involved ROS production that was due to the occurrence of ferritinophagy. More interestingly, DpdtC could also inhibit EMT, leading to the upregulation of E-cadherin and the downregulation of vimentin; however, the addition of NAC and 3-MA could attenuate (or neutralize) the action of DpdtC on ferritinophagy induction and EMT inhibition, supporting that the enhanced ferritinophagic flux contributed to the EMT inhibition. Since the degradation of ferritin may trigger the production of ROS and induce the response of p53, we next studied the role of p53 in the above two-cell events. As expected, an upregulation of p53 was observed after DpdtC insulting; however, the addition of a p53 inhibitor, PFT-α, could significantly attenuate the action of DpdtC on ferritinophagy induction and EMT inhibition. In addition, autophagy inhibitors or NAC could counteract the effect of DpdtC and restore the level of p53 to the control group, indicating that the upregulation of p53 was caused by ferritinophagy-mediated ROS production. In conclusion, our data demonstrated that the inhibition of EMT induced by DpdtC was realized through ferritinophagy-mediated ROS/p53 pathway, which supported that the activation of ferritinophagic flux was the main driving force in EMT inhibition in gastric cancer cells, and further strengthening the concept that NCOA4 participates in EMT process.

Ferritinophagic Flux Activation in CT26 Cells Contributed to EMT Inhibition Induced by a Novel Iron Chelator, DpdtpA.

Epithelial-mesenchymal transition (EMT) contributes to metastasis and drug resistance; inhibition of EMT may attenuate metastasis and drug resistance. It has been demonstrated that ferritinophagy involves the process of many diseases; however, the relationship between EMT and ferritinophagy was not fully established. Some iron chelators show the ability to inhibit EMT, but whether ferritinophagy plays a role in EMT is largely unknown. To this end, we investigated the effect of a novel iron chelator, DpdtpA (2,2 '-di-pyridylketone dithiocarbamate propionic acid), on EMT in the CT26 cell line. The DpdtpA displayed excellent antitumor (IC50 = 1.5 ± 0.2 µM), leading to ROS production and apoptosis occurrence. Moreover, the ROS production correlated with ferritin degradation. The upregulation of LC3-II and NCOA4 from immunofluorescence and Western blotting analysis revealed that the occurrence of ferritinophagy contributed to ROS production. Furthermore, DpdtpA could induce an alteration both in morphology and in epithelial-mesenchymal markers, displaying significant EMT inhibition. The correlation analysis revealed that DpdtpA-induced ferritinophagy contributed to the EMT inhibition, implying that NCOA4 involved EMT process, which was firstly reported. To reinforce this concept, the ferritinophagic flux (NCOA4/ferritin) in either treated by TGF-ß1 or combined with DpdtpA was determined. The results indicated that activating ferritinophagic flux would enhance ROS production which accordingly suppressed EMT or implementing the EMT suppression seemed to be through "fighting fire with fire" strategy. Taken together, our data demonstrated that ferritinophagic flux was a dominating driving force in EMT proceeding, and the new finding definitely will enrich our knowledge of ferritinophagy in EMT process.

ZrO2 nanoparticles confined in metal organic frameworks for highly effective adsorption of phosphate.

Highly dispersed ZrO2 particles confined in the MIL-101 (denoted as MIL-101@Zr(DS)) with varied ZrO2 loading amounts were prepared by the double solvents method. For comparison, ZrO2 loaded MIL-101 samples were synthesized by the conventional impregnation method (denoted as MIL-101@Zr(I)) and the deposition method (denoted as MIL-101@Zr(D)). The characterization results indicated that for MIL-101@Zr(DS), ZrO2 particles were dominantly confined in MIL-101 with a much higher dispersion as compared with MIL-101@Zr(I) and MIL-101@Zr(D). The maximum phosphate adsorption capacity and ZrO2 content normalized phosphate adsorption capacity of the MIL-101@Zr(DS) were 21.28 mg P·g-1 and 1120.0 mg P·g-1, respectively. Additionally, the ZrO2 content normalized phosphate adsorption capacity was significantly larger than that for MIL-101@Zr(I) and MIL-101@Zr(D) as well as the reported values for other Zr-based adsorbents. The effects of solution chemistry on phosphate adsorption to MIL-101@Zr(DS), MIL-101@Zr(I) and MIL-101@Zr(D) were also examined. Compared with MIL-101@Zr(I) and MIL-101@Zr(D), the adsorption of phosphate on MIL-101@Zr(DS) was less affected by the coexistence of anions and dissolved humic acid. Increasing pH from 3 to 12 led to decreased phosphate adsorption capacity of MIL-101@Zr(DS) from 10.38 mg P·g-1 to 2.03 mg P·g-1. Accordingly, used MIL-101@Zr(DS) could be effectively regenerated under alkaline conditions and exhibited stable adsorption-desorption performance.