Design, synthesis, and evaluation of cyclic C7-bridged monocarbonyl curcumin analogs containing an o-methoxy phenyl group as potential agents against gastric cancer.

The structure-activity relationship (SAR) between toxicity and the types of linking ketones of C7 bridged monocarbonyl curcumin analogs (MCAs) was not clear yet. In the pursuit of effective and less cytotoxic chemotherapeutics, we conducted a SAR analysis using various diketene skeletons of C7-bridged MCAs, synthesized cyclic C7-bridged MCAs containing the identified low-toxicity cyclopentanone scaffold and an o-methoxy phenyl group, and assessed their anti-gastric cancer activity and safety profile. Most compounds exhibited potent cytotoxic activities against gastric cancer cells. We developed a quantitative structure-activity relationship model (R2 > 0.82) by random Forest method, providing important information for optimizing structure. An optimized compound 2 exhibited in vitro and in vivo anti-gastric cancer activity partly through inhibiting the AKT and STAT3 pathways, and displayed a favorable in vivo safety profile. In summary, this paper provided a promising class of MCAs and a potential compound for the development of chemotherapeutic drugs.

DCT-Net: An effective method to diagnose retinal tears from B-scan ultrasound images.

Retinal tears (RTs) are usually detected by B-scan ultrasound images, particularly for individuals with complex eye conditions. However, traditional manual techniques for reading ultrasound images have the potential to overlook or inaccurately diagnose conditions. Thus, the development of rapid and accurate approaches for the diagnosis of an RT is highly important and urgent. The present study introduces a novel hybrid deep-learning model called DCT-Net to enable the automatic and precise diagnosis of RTs. The implemented model utilizes a vision transformer as the backbone and feature extractor. Additionally, in order to accommodate the edge characteristics of the lesion areas, a novel module called the residual deformable convolution has been incorporated. Furthermore, normalization is employed to mitigate the issue of overfitting and, a Softmax layer has been included to achieve the final classification following the acquisition of the global and local representations. The study was conducted by using both our proprietary dataset and a publicly available dataset. In addition, interpretability of the trained model was assessed by generating attention maps using the attention rollout approach. On the private dataset, the model demonstrated a high level of performance, with an accuracy of 97.78%, precision of 97.34%, recall rate of 97.13%, and an F1 score of 0.9682. On the other hand, the model developed by using the public funds image dataset demonstrated an accuracy of 83.82%, a sensitivity of 82.69% and a specificity of 82.40%. The findings, therefore present a novel framework for the diagnosis of RTs that is characterized by a high degree of efficiency, accuracy and interpretability. Accordingly, the technology exhibits considerable promise and has the potential to serve as a reliable tool for ophthalmologists.

Discovery of Pyroptosis-inducing Drugs and Antineoplastic Activity Based on the ROS/ER Stress/Pyroptosis Axis.

BACKGROUND: Pyroptosis, a cell death process triggered by chemotherapy drugs, has emerged as a highly promising mechanism for combating tumors in recent years. As the lead of new drugs, natural products play an important role in the discovery of anticancer drugs. Compared to other natural products, the medicine food homologous natural products (MFHNP) exhibit a superior safety profile. Among a series of MFHNP molecular skeletons, this study found that only benzylideneacetophenone (1) could induce cancer cell pyroptosis. However, the anti-cancer activity of 1 remains to be improved. AIMS: This study aimed to find a pyroptosis inducer with highly effective antitumor activity by modifying the chalcone structure. METHODS: To examine the effect of the Michael receptor in compound 1 on the induction of pyroptosis, several analogs were synthesized by modifying the Michael acceptor. Subsequently, the anticancer activity was tested by MTT assay, and morphological indications of pyroptosis were observed in human lung carcinoma NCI-H460 and human ovarian cancer CP-70 cell lines. Furthermore, to improve the activity of the chalcone skeleton, the anticancer group 3,4,5- trimethoxyphenyl was incorporated into the phenyl ring. Subsequently, compounds 2-22 were designed, synthesized, and screened in human lung cancer cells (NCI-H460, H1975, and A549). Additionally, a quantitative structure-activity relationship (QSAR) model was established using the eXtreme Gradient Boosting (XGBoost) machine learning library to identify the pharmacophore. Furthermore, both in vitro and in vivo experiments were conducted to investigate the molecular mechanisms of pyroptosis induced by the active compound. RESULTS: α, ß-unsaturated ketone was the functional group of the chalcone skeleton and played a pivotal role in inducing cancer cell pyroptosis. QSAR models showed that the regression coefficients (R2) were 0.992 (A549 cells), 0.990 (NCI-H460 cells), and 0.998 (H1975 cells). Among these compounds, compound 7 was selected to be the active compound. Moreover, compound 7 was found to induce pyroptosis in lung cancer cells by upregulating the expression of CHOP by increasing the ROS level. Furthermore, it effectively suppressed the growth of lung cancer xenograft tumors. CONCLUSION: Compound 7 exhibits antineoplastic activity by regulating the ROS/ER stress/pyroptosis axis and is a kind of promising pyroptosis inducer.

Green synthesis and anti-tumor efficacy via inducing pyroptosis of novel 1H-benzo[e]indole-2(3H)-one spirocyclic derivatives.

Pyroptosis induction is anticipated to be a new approach to developing anti-tumor medications. A novel class of spirocyclic compounds was designed by hybridization of 1H-Benzo[e]indole-2(3H)-one with 1,4-dihydroquinoline and synthesized through a new green "one-pot" synthesis method using 10 wt% SDS/H2O as a solvent to screen novel tumor cell pyroptosis inducers. The anti-tumor activity of all compounds in vitro was determined by the MTT method, and a fraction of the compounds showed good cell growth inhibitory activity. The quantitative structure-activity relationship models of the compounds were established by artificial intelligence random forest algorithm (R2 = 0.9656 and 0.9747). The ideal compound A9 could, in a concentration-dependent manner, prevent ovarian cancer cells from forming colonies, migrating, and invading. Furthermore, A9 could significantly induce pyroptosis and upregulate the expression of pyroptosis-related proteins GSDME-N, in addition to inducing apoptosis and mediating the expression of apoptosis-related proteins in ovarian cancer cells. A9 (5 mg/kg) significantly reduced tumor volume and weight of ovarian cancer in vivo, decreased caspase-3 expression in tumor tissue, and induced the production of GSDME-N. This study provides a green and efficient atom-economic synthesis method for 1H-Benzo[e]indole-2(3H)-one spirocyclic derivatives and a promising pyroptosis inducer with anti-tumor activity.

Elucidating the potential effects of point mutations on FGFR3 inhibitor resistance via combined molecular dynamics simulation and community network analysis.

FGFR3 kinase mutations are associated with a variety of malignancies, but FGFR3 mutant inhibitors have rarely been studied. Furthermore, the mechanism of pan-FGFR inhibitors resistance caused by kinase domain mutations is still unclear. In this study, we try to explain the mechanism of drug resistance to FGFR3 mutation through global analysis and local analysis based on molecular dynamics simulation, binding free energy analysis, umbrella sampling and community network analysis. The results showed that FGFR3 mutations caused a decrease in the affinity between drugs and FGFR3 kinase, which was consistent with the reported experimental results. Possible mechanisms are that mutations affect drug-protein affinity by altering the environment of residues near the hinge region where the protein binds to the drug, or by affecting the A-loop and interfering with the allosteric communication networks. In conclusion, we systematically elucidated the underlying mechanism of pan-FGFR inhibitor resistance caused by FGFR3 mutation based on molecular dynamics simulation strategy, which provided theoretical guidance for the development of FGFR3 mutant kinase inhibitors.

An innovative immunotherapeutic strategy for rheumatoid arthritis: Selectively suppressing angiogenesis and osteoclast differentiation by fully human antibody targeting thymocyte antigen-1.

Thymocyte antigen-1 (THY-1)is a potential target for rheumatoid arthritis (RA) treatment, and THY-1 positive fibroblast-like synoviocytes (FLS) are enriched in the synovium of RA patients and participate in angiogenesis to accelerate RA progression. In this study, we screened an antibody targeting THY-1 (THY-1 Ab) and explored its mechanism in alleviating RA progression. THY-1 Ab was screened from ScFv phage antibody library by phage display technology (PDT). THY-1 Ab-treated collagen induced arthritis (CIA) mice had lower degree of arthritis scores. We explore the mechanism of THY-1 Ab in alleviating RA progression. THY-1 Ab can remarkably inhibit the secretion of pro-inflammatory factors and promote the secretion of anti-inflammatory factors. Further experiments showed that THY1 Ab downregulated the expression of JUNB by the hsa_circ_0094342/miRNA-155-5P/SPI1 axis, inhibited RA angiogenesis and osteoclast differentiation, and relieved RA progression. These findings support that THY-1 Ab is a promising therapeutic antibody for RA treatment.

Erratum: Author correction to 'Design, synthesis and biological evaluation of chalcone analogues with novel dual antioxidant mechanisms as potential anti-ischemic stroke agents' [Acta Pharmaceutica Sinica B 9 (2019) 335-350].

[This corrects the article DOI: 10.1016/j.apsb.2019.01.003.].

Rational design, synthesis, and pharmacological characterisation of dicarbonyl curcuminoid analogues with improved stability against lung cancer via ROS and ER stress mediated cell apoptosis and pyroptosis.

Curcumin is a natural medicine with a wide range of anti-tumour activities. However, due to ß-diketone moiety, curcumin exhibits poor stability and pharmacokinetics which significantly limits its clinical applications. In this article, two types of dicarbonyl curcumin analogues with improved stability were designed through the calculation of molecular stability by density functional theory. Twenty compounds were synthesised, and their anti-tumour activity was screened. A plurality of analogues had significantly stronger activity than curcumin. In particular, compound B2 ((2E,2'E)-3,3'-(1,4-phenylene)bis(1-(2-chlorophenyl)prop-2-en-1-one)) exhibited excellent anti-lung cancer activity in vivo and in vitro. In addition, B2 could upregulate the level of reactive oxygen species in lung cancer cells, which in turn activated the endoplasmic reticulum stress and led to cell apoptosis and pyroptosis. Taken together, curcumin analogue B2 is expected to be a novel candidate for lung cancer treatment with improved chemical and biological characteristics.

Discovery and evaluation of chalcone derivatives as novel potential anti-Toxoplasma gondii agents.

Due to numerous side effects of traditional treatments for toxoplasmosis, it is urgent to develop new anti-Toxoplasma agents with high efficiency and low toxicity. In this study, using drug-food-homologous chalcone skeleton as a leading compound, 6 series of chalcone derivatives were designed, synthesized, and almost 1/2 compounds have good anti-Toxoplasma activity in vitro. The quantitative structure-activity relationship model of the anti-Toxoplasma activity of the second batch of compounds was established by random forest method (R2 = 0.9407). The Michael receptor in the molecular skeleton of chalcones plays an important role in improving the activity. Among these compounds, four chalcone derivatives exhibited potent anti-T. gondii activity and low cytotoxicity in vitro. Specifically, three of them (4a, 4c and 5e) effectively inhibited the proliferation of Toxoplasma tachyzoites in vivo. Liver and spleen index and biochemical parameters, such as alanine aminotransferase, aspartate aminotransferase and malondialdehyde were significantly decreased by the three chalcone derivatives, suggesting that they have protective effects on the liver of mice infected with Toxoplasma tachyzoites. Overall, this article provides a series of promising compounds for the development of anti-Toxoplasma agents.

Design, green synthesis, antioxidant activity screening, and evaluation of protective effect on cerebral ischemia reperfusion injury of novel monoenone monocarbonyl curcumin analogs.

Antioxidants with high efficacy and low toxicity have the potential to treat cerebral ischemia reperfusion injury (CIRI). Dienone monocarbonyl curcumin analogs (DMCA) capable of overcoming the instability and pharmacokinetic defects of curcumin possess notable antioxidant activity but are found to be significantly toxic. In this study, a novel skeleton of the monoenone monocarbonyl curcumin analogue sAc possessing reduced toxicity and improved stability was designed on the basis of the DMCA skeleton. Moreover, 32 sAc analogs were obtained by applying a green, simple, and economical synthetic method. Multiple sAc analogs with an antioxidant protective effect in PC12 cells were screened using an H2O2-induced oxidative stress damage model, and quantitative evaluation of structure-activity relationship (QSAR) model with regression coefficient of R2 = 0.918921 was built through random forest algorithm (RF). Among these compounds, the optimally active compound sAc15 elicited a potent protective effect on cell growth of PC12 cells by effectively eliminating ROS generation in response to oxidative stress injury by activating the Nrf2/HO-1 antioxidant signaling pathway. In addition, sAc15 exhibited good protection against CIRI in the mice middle cerebral artery occlusion (MCAO) model. In this paper, we provide a novel class of antioxidants and a potential compound for stroke treatment.

Design and Synthesis of Novel Nordihydroguaiaretic Acid (NDGA) Analogues as Potential FGFR1 Kinase Inhibitors With Anti-Gastric Activity and Chemosensitizing Effect.

Aberrant fibroblast growth factor receptor-1 (FGFR1), a key driver promoting gastric cancer (GC) progression and chemo-resistance, has been increasingly recognized as a potential therapeutic target in GC. Hereon, we designed and synthesized a series of asymmetric analogues using Af23 and NDGA as lead compounds by retaining the basic structural framework (bisaryl-1,4-dien-3-one) and the unilateral active functional groups (3,4-dihydroxyl). Thereinto, Y14 showed considerable inhibitory activity against FGFR1. Next, pharmacological experiments showed that Y14 could significantly inhibit the phosphorylation of FGFR1 and its downstream kinase AKT and ERK, thus inhibiting the growth, survival, and migration of gastric cancer cells. Furthermore, compared with 5-FU treatment alone, the combination of Y14 and 5-FU significantly reduced the phosphorylation level of FGFR1, and enhanced the anti-cancer effect by inhibiting the viability and colony formation in two gastric cancer cell lines. These results confirmed that Y14 exerted anti-gastric activity and chemosensitizing effect by inhibiting FGFR1 phosphorylation and its downstream signaling pathway in vitro. This work also provides evidence that Y14, an effective FGFR1 inhibitor, could be used alone or in combination with chemotherapy to treat gastric cancer in the future.

[Effects of low intensity resistance training of blood flow restriction with different occlusion pressure on lower limb muscle and cardiopulmonary function of college students].

Objective: The study compared the effects of low intensity resistance training with blood flow restriction (BFR) with different occlusion pressure on lower limb muscle and cardiopulmonary function. Methods: Twenty-seven college students were randomly divided into three groups by different occlusion pressure: 0 mmHg (group C), 120 mmHg (group L) and 180 mmHg (group H). Before and after training (3 times a week for 12 weeks) with an inflatable cuff (20% 1RM, half squat), the muscle thickness(MTH)of rectus femoris and medius femoris, relative peak knee extensor moment(rM), peak power(P), relative maximal oxygen uptake(rVO2max), stroke volume(SV), cardiac output(CO), ejection fraction(EF) and other indicators were measured for all subjects. Results: When compared with pre-training, and rectus femoris, the MTH of medius femoris, rM, rVO2max, SV, CO and EF were significantly increased in group L and group H after 12 weeks training(P＜0.05, P＜0.01), as well as compared with group C after training(P＜0.05, P＜0.01). There was no significant difference between group L and group H after training. Conclusion: BFR training protocols under 120 mmHg or 180 mmHg pressure were effective in improving muscle and cardiopulmonary function.

The discovery of potent and stable short peptide FGFR1 antagonist for cancer therapy.

Fibroblast growth factor receptor 1 (FGFR1) is one of the attractive pharmaceutical targets for cancer therapy. The FGFR1 targeting antagonist peptides, especially of the short peptides harbouring only coding amino acid might highlights promising aspects for their higher affinity, specificity and lower adverse reactions. However, most of peptides inhibitors remain in preclinical research, likely associating with their instability and short half-life. In this study, we found a stable short peptide inhibitor P48 and speculated that its stability might be related to its non-linear spatial structure. In addition, P48 could target the extracellular immunoglobulin domain of FGFR1, and effectively block the particular signaling pathways of FGFR1, which lead to the inhibition of cancer proliferation, invasion in vitro and restraint of tumor growth in vivo. Together, this study provided a promising FGFR1 inhibitor with the potential to be developed as an antitumor drug.

Piperlongumine analogue L50377 induces pyroptosis via ROS mediated NF-κB suppression in non-small-cell lung cancer.

Natural products with potent activity and less toxicity provide major sources for development of novel anti-cancer drugs. Herein, we evaluated the effects and the underlying mechanisms of a novel piperlongumine (PL) analogue L50377 on non-small-cell lung cancer (NSCLC) cells. The results revealed that L50377 displayed greater potentials of suppressing cell growth than PL. In addition, L50377 promoted cell apoptosis and pyroptosis via stimulating reactive oxygen species (ROS) generation in NSCLC cells. More interestingly, ROS mediated NF-κB suppression might be implicated in the mechanisms of L50377-induced pyroptosis in NSCLC cells. Taken together, our results suggested that L50377 served as a novel chemical agent might have great potentials for NSCLC treatment.

Design and Green Synthesis of Piperlongumine Analogs and Their Antioxidant Activity against Cerebral Ischemia-Reperfusion Injury.

The supplementation of exogenous antioxidants to scavenge excessive reactive oxygen species (ROS) is an effective treatment for cerebral ischemia-reperfusion injury (CIRI) in stroke. Piperlongumine (PL), a natural alkaloid, has a great potential as a neuroprotective agent, but it also has obvious toxicity. Moreover, its neuroprotective effects remain to be improved. In this study, we designed a series of novel PL analogs by hybridizing the screened low-toxicity diketene skeleton with antioxidant effect and the 3,4,5-trimethoxyphenyl group, which may increase the antioxidant activity of PL. The intermediate was synthesized by a novel green synthesis method, and 34 compounds were obtained. The compounds without obvious cytotoxicity have remarkable antioxidant effects, especially compared with diketene skeletons and PL. The cytoprotection of the active compound decreased significantly by reduction of the carbon-carbon double bonds of the Michael acceptor in the diketene skeleton. More importantly, further study revealed that compound A9, which has the best activity, can confer protection for cells against oxidative stress and attenuate brain injury in vivo. Overall, this study provided a promising drug candidate for the treatment of CIRI and guided the further development of drug research in oxidative stress-mediated diseases.

Design, synthesis and biological evaluation of chalcone analogues with novel dual antioxidant mechanisms as potential anti-ischemic stroke agents.

Scavenging reactive oxygen species (ROS) by antioxidants is the important therapy to cerebral ischemia-reperfusion injury (CIRI) in stroke. The antioxidant with novel dual-antioxidant mechanism of directly scavenging ROS and indirectly through antioxidant pathway activation may be a promising CIRI therapeutic strategy. In our study, a series of chalcone analogues were designed and synthesized, and multiple potential chalcone analogues with dual antioxidant mechanisms were screened. Among these compounds, the most active 33 not only conferred cytoprotection of H2O2-induced oxidative damage in PC12 cells through scavenging free radicals directly and activating NRF2/ARE antioxidant pathway at the same time, but also played an important role against ischemia/reperfusion-related brain injury in animals. More importantly, in comparison with mono-antioxidant mechanism compounds, 33 exhibited higher cytoprotective and neuroprotective potential in vitro and in vivo. Overall, our findings showed compound 33 could emerge as a promising anti-ischemic stroke drug candidate and provided novel dual-antioxidant mechanism strategies and concepts for oxidative stress-related diseases treatment.

Design, synthesis, and evaluation of chalcone analogues incorporate α,ß-Unsaturated ketone functionality as anti-lung cancer agents via evoking ROS to induce pyroptosis.

Chalcone, a natural structure, demonstrates many pharmacological activities including anticancer, and one promising mechanism is to modulate the generation of ROS. It has been known that pyroptosis is associated with anticancer effects, whereas there is fewer researches about ROS-mediated pyroptosis triggered by chemotherapy drugs. Moreover, incorporation of a α,ß-unsaturated ketone unit into chalcone may be an effective strategy for development of chemotherapy drugs. Hence, a number of chalcone analogues bearing a α,ß-unsaturated ketone were synthesized from chalcone analogues 1 with modest anticancer activities as the lead compound. Structure-activity relationship (SAR) studies confirmed the function of α,ß-unsaturated ketone to improve anticancer activity. Notably, compound 8, bearing a α,ß-unsaturated ketone, is the most potent inhibitor of cancer, with IC50 values on NCI-H460, A549 and H1975 cells of 2.3 ±â€¯0.3, 3.2 ±â€¯0.0 and 5.7 ±â€¯1.4 µM, respectively. Besides, 8 showed antiproliferative ability against NCI-H460 cells in a time- and concentration-dependent manner through modulating ROS to induce caspase-3-mediated pyroptosis, and displayed a better safety profile in vivo. Overall, these results demonstrated that compound 8 is a candidate agent and a potential lead compound for development of chemotherapy drugs, and can be used as a probe to further examine the mechanism of ROS-dependent pyroptosis.

Synthesis and anti-tumor activity of EF24 analogues as IKKß inhibitors.

EF24 is an IKKß inhibitor (IC50: 72 µM) containing various anti-tumor activities. In this study, a series of EF24 analogs targeting IKKß were designed and synthesized. Several IKKß inhibitors with better activities than EF24 were screened out and B3 showed best IKKß inhibitory (IC50: 6.6 µM). Molecular docking and dynamic simulation experiments further confirmed this inhibitory effect. B3 obviously suppressed the viability of Hela229, A549, SGC-7901 and MGC-803 cells. Then, in SGC-7901 and MGC-803 cells, B3 blocked the NF-κB signal pathway by inhibiting IKKß phosphorylation, and followed arrested the cell cycle at G2/M phase by suppressing the Cyclin B1 and Cdc2 p34 expression, induced the cell apoptosis by down-regulating Bcl-2 protein and up-regulating cleaved-caspase3. Moreover, B3 significantly reduced tumor growth and suppressed the IKKß-NF-κB signal pathway in SGC-7901 xenograft model. In total, this study present a potential IKKß inhibitor as anti-tumor precursor.

Design, synthesis, and evaluation of NDGA analogues as potential anti-ischemic stroke agents.

Exogenous supplementation of antioxidants with ROS scavenging activity would be a potential therapy to cerebral ischemia-reperfusion injury in stroke. In the present study, a series of NDGA analogues with attenuation oxidative stress by directly scavenging ROS and indirectly through keap1/Nrf2/ARE pathway activation were designed and synthesized. All analogues were found to effectively remove ROS directly by DPPH radical scavenging assay, and compound 3a conferred potent protection from the oxidative injury in PC12 cells via promoting Nrf2 to translocate into nucleus and increasing expression of heme oxygenase-1(HO-1), where strongly reduced intracellular ROS level indirectly. More importantly, 3a significantly reduced brain infarction after cerebral ischemia-reperfusion injury in rats subjected to transient middle cerebral artery occlusion (MCAO). Overall, our findings shown compound 3a could serve as a promising compound for the treatment of stroke.