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Background: Hepatocellular carcinoma (HCC) is a common cancer that is fatal and has a dismal prognosis. Obovatol (Ob), a novel lignan derived from the leaf and stem bark of Magnolia obovata Thunb, has exhibited anti-tumor effect on diverse tumors. However, its effect and mechanisms on HCC remain to be further explored., Methods: Huh7 and Hep3B cells, as well as BALB/c nude mice were used to determine the function and mechanisms of Ob on growth, invasion and immune escape by cell counting kit-8, transwell, enzyme-linked immunosorbent assay (ELISA) and western blot experiments., Results: Ob reduced the cell viability of Huh7 and Hep3B cells, with a IC50 value of 57.41 µM and 62.86 µM, respectively. Ob declined the invasion ability, the protein expression of N-cadherin and the concentrations of IL-10 and TGF-β, whereas increased the E-cadherin expression and the contents of IFN-γ and IL-2 in Hep3B and Huh7 cells. Mechanically, Ob decreased the protein level of p-JAK/JAK, p-STAT3/STAT3 and PD-L1, which was partly restored with the treatment of RO8191, an activator of JAK/STAT3 axis. The effect of Ob on the cell viability, the invasion ability, the protein level of N-cadherin and E-cadherin, and the concentrations of IL-10, TGF-β, IFN-γ and IL-2 in both Hep3B and Huh7 cells was reversed with the management of RO8191. In vivo, Ob reduced tumor volume and weight, the level of N-cadherin, PD-L1, p-JAK/JAK, and p-STAT3/STAT3, with an elevated expression of E-cadherin and IFN-γ., Conclusion: Ob downregulated the JAK/STST3/PD-L1 pathway to attenuate the growth, invasion and immune escape of HCC., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Congenital diaphragmatic hernia (CDH) is a rare disease that affects the development of the diaphragm, leading to abnormal lung development. Unfortunately, there is no established therapy for CDH. Retinoic acid pathways are implicated in the ethology of CDH and macrophages are known to play a role in repairing organ damage., Methods: We have analyzed the effect of several Toll like receptor (TLR) ligands in the nitrofen-induced CDH model in pregnant rats widely used to study this disease and in the G2-GATA4 Cre ;Wt1 fl/fl CDH genetic mice model. Morphometric and histological studies were carried out. Immune cell infiltration was assayed by immunochemistry and immunofluorescence and retinoic pathway gene expression analyzed in vivo and in vitro in macrophages., Results: We found that administering a single dose of atypical TLR2/4 ligands (CS1 or CS2), 3 days after nitrofen, cured diaphragmatic hernia in 73% of the fetuses and repaired the lesion with complete diaphragm closure being on the other hand nontoxic for the mothers or pups. Moreover, these immunomodulators also improved pulmonary hypoplasia and alveolar maturation and vessel hypertrophy, enhancing pulmonary maturity of fetuses. We also found that CS1 treatment rescued the CDH phenotype in the G2-GATA4 Cre ;Wt1 fl/fl CDH genetic mice model. Only 1 out of 11 mutant embryos showed CDH after CS1 administration, whereas CDH prevalence was 70% in untreated mutant embryos. Mechanistically, CS1 stimulated the infiltration of repairing M2 macrophages (CD206 + and Arg1 + ) into the damaged diaphragm and reduced T cell infiltration. Additionally, those TLR ligands induced retinol pathway genes, including RBP1, RALDH2, RARα, and RARβ, in the affected lungs and the diaphragm and in macrophages in vitro., Conclusions: Our research has shown that TLR ligand immunomodulators that influence anti-inflammatory macrophage activation can be effective in treating CDH, being nontoxic for the mothers or pups suggesting that those TLR ligands are a promising solution for CDH leading to orphan drug designation for CS1. The immune system of the fetus would be responsible for repairing the damage and closure of the hernia in the diaphragm and enhanced proper lung development after CS1 treatment., (© 2024. The Author(s).)

Background: Succinate dehydrogenase inhibitor (SDHI) fungicides play important roles in the control of plant fungal diseases. However, they are facing serious challenges from issues with resistance and cross-resistance, primarily attributed to their frequent application and structural similarities. There is an urgent need to design and develop SDHI fungicides with novel structures., Results: Aiming to discover novel potent SDHI fungicides, 31 innovative pyrazole β-ketonitrile derivatives with diphenyl ether moiety were rationally designed and synthesized, which were guided by a 3D-QSAR model from our previous study. The optimal target compound A23 exhibited not only outstanding in vitro inhibitory activities against Rhizoctonia solani with a half-maximal effective concentration (EC 50 ) value of 0.0398 μg mL -1 comparable to that for fluxapyroxad (EC 50  = 0.0375 μg mL -1 ), but also a moderate protective efficacy in vivo against rice sheath blight. Porcine succinate dehydrogenase (SDH) enzymatic inhibitory assay revealed that A23 is a potent inhibitor of SDH, with a half-maximal inhibitory concentration of 0.0425 μm. Docking study within R. solani SDH indicated that A23 effectively binds into the ubiquinone site mainly through hydrogen-bonds, and cation-π and π-π interactions., Conclusion: The identified β-ketonitrile compound A23 containing diphenyl ether moiety is a potent SDH inhibitor, which might be a good lead for novel fungicide research and optimization. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Repositioning approved antitumor drugs for different cancers is a cost-effective approach. Gilteritinib was FDA-approved for the treatment of FLT3-mutated acute myeloid leukemia in 2018. However, the therapeutic effects and mechanism of Gilteritinib on other malignancies remain to be defined. In this study, we identified that gilteritinib has an inhibitory effect on lung cancer cells (LCCs) without FLT3 mutation in vitro and in vivo. Unexpectedly, we found that gilteritinib induces cholesterol accumulation in LCCs via upregulating cholesterol biosynthetic genes and inhibiting cholesterol efflux. This gilteritinib-induced cholesterol accumulation not only attenuates the antitumor effect of gilteritinib but also induces gilteritinib-resistance in LCCs. However, when cholesterol synthesis was prevented by squalene epoxidase (SQLE) inhibitor NB-598, both LCCs and gilteritinib-resistant LCCs became sensitive to gilteritinib. More importantly, the natural cholesterol inhibitor 25-hydroxycholesterol (25HC) can suppress cholesterol biosynthesis and increase cholesterol efflux in LCCs. Consequently, 25HC treatment significantly increases the cytotoxicity of gilteritinib on LCCs, which can be rescued by the addition of exogenous cholesterol. In a xenograft model, the combination of gilteritinib and 25HC showed significantly better efficacy than either monotherapy in suppressing lung cancer growth, without obvious general toxicity. Thus, our findings identify an increase in cholesterol induced by gilteritinib as a mechanism for LCC survival, and highlight the potential of combining gilteritinib with cholesterol-lowering drugs to treat lung cancer., (© 2024. The Author(s).)

Epidermal growth factor receptor (EGFR) is a validated target for non-small-cell lung cancer (NSCLC). However, the treatment for EGFR-C797S mutation induced by third-generation EGFR inhibitors remains a concern. Therefore, the development of the fourth-generation EGFR inhibitors to overcome the EGFR-C797S mutation has great potential for clinical treatment. In this article, we designed and synthesized a series of diphenyl ether substituted quinazolin-4-amine derivatives that simultaneously occupy the ATP binding pocket and the allosteric site of EGFR. Among the newly synthesized compounds, 9d displayed excellent kinase activity against EGFR L858R/T790M/C797S with an IC 50 value of 0.005 μM, and exhibited anti-proliferation activity in BaF3-EGFR L858R/T790M/C797S cells with the IC 50 value of 0.865 μM. Furthermore, 9d could suppress phosphorylation of EGFR and induce cell apoptosis and cycle arrest at G2 phase in a dose-dependent manner in BaF3-EGFR L858R/T790M/C797S cells. More importantly, 9d displayed significant antitumor effects in BaF3-EGFR L858R/T790M/C797S xenograft mouse model (30 mg/kg, TGI = 71.14 %). All the results indicated compound 9d might be a novel fourth-generation EGFR inhibitor for further development in overcoming the EGFR-C797S resistance mutation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Given the prevalence of the malignant weed Chinese Sprangletop ( Leptochloa chinensis (L.) Nees) in rice fields, the development of novel herbicides against this weed has aroused wide interest. Here, we report a novel diphenyl ether-pyrimidine hybrid, DEP- 5 , serving as a systematic pre/postemergence herbicide candidate for broad-spectrum weed control in rice fields, specifically for L. chinensis . Notably, DEP- 5 exhibits over 80% herbicidal activity against the resistant biotypes even at 37.5 g a.i./ha under greenhouse conditions and has complete control of L. chinensis at 150 g a.i./ha in the rice fields. We uncover that DEP- 5 acts as a noncompetitive inhibitor of acetohydroxyacid synthase (AHAS) with an inhibition constant ( K i ) of 39.4 μM. We propose that DEP- 5 binds to AHAS in two hydrophobic-driven binding modes that differ from commercial AHAS inhibitors. Overall, these findings demonstrate that DEP- 5 has great potential to be developed into a herbicide for L. chinensis control and inspire fresh concepts for novel AHAS-inhibiting herbicide design.

Background: Phytopathogenic bacteria cause severe losses to crops every year. The management of crop bacterial diseases with chemical agents has been considered as the main strategy. In order to cope with the bactericide resistance made by the pathogens, new antibacterials need to be continuously developed., Results: A chemical investigation from the endophytic fungus Rhexocercosporidium sp. Dzf14 has led to the isolation of 12 diphenyl ethers including two new ones named rhexocerin E (1) and rhexocercosporin G (2), along with two new depsides named rhexocerdepsides A (3) and B (4). The structures and absolute configurations of the new compounds were determined through comprehensive analysis of spectroscopic data and quantum chemical ECD calculations. Diphenyl ethers showed obviously antibacterial activity on Gram-positive bacteria. The structure-activity relationship of diphenyl ethers revealed that prenylation was critical to the antibacterial activity. Among them, rhexocercosporin D (12) possessed the strongest activity against Clavibacter michiganensis and Bacillus subtilis, and was selected for further mechanistic studies. It was found that rhexocercosporin D displayed bactericidal activity by affecting homeostasis of cell membranes. In addition to its rapid bactericidal effects on Gram-positive bacteria, rhexocercosporin D could restore the susceptibility against Gram-negative Agrobacterium tumefaciens by synergistic action with colistin., Conclusion: Twelve diphenyl ethers and two depsides were isolated from endophytic fungus Rhexocercosporidium sp. Dzf14. Isopentenyl was critical for diphenyl ethers against Gram-positive bacteria. Rhexocercosporin D could affect homeostasis of bacterial cell membrane to exert rapid bactericidal activity. These findings highlight the antibacterial potential of the diphenyl ethers in crop bacterial disease management. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Background: Severe pulmonary hypoplasia related to congenital diaphragmatic hernia (CDH) continues to be a potentially fatal condition despite advanced postnatal management strategies., Objective: To evaluate the effect of the antenatal sildenafil and 2(S)-amino-6-boronohexanoic acid (ABH-Arginase inhibitor) on lung volume, pulmonary vascular development, and nitric oxide (NO) synthesis in a Nitrofen-induced CDH rat model., Methods: Nitrofen-induced CDH rat model was used. Nitrofen was administrated on embryonic day(E) 9,5. At E14, five intervention groups were treated separately: Nitrofen, Nitrofen+Sildenafil, Nitrofen+ABH, Nitrofen+Sildenafil+ABH and Control. At term, offspring's lungs were weighed, some paraffin-embedded for histology, others snap-frozen to analyze eNOS, Arginase I-II expression, and activity., Results: In CDH-bearing offsprings, ABH or Sildenafil+ABH preserved the total lung/body-weight index (p < 0.001), preventing pulmonary vascular smooth muscle cell hyperproliferation and improving lung morphometry. Sildenafil+ABH increased 1.7-fold the lung nitrite levels (p < 0.01) without changes in eNOS expression. Sildenafil and ABH improved the number of pulmonary vessels., Conclusion: These results suggest that in this CDH rat model, the basal activity of Arginase participates in the lung volume and, together with phosphodiesterase-5, regulates NOS activity in the term fetal lung. The combined treatment (Sildenafil+ABH) could revert some of the pulmonary features in CDH by improving the local NO synthesis and preventing smooth muscle cell hyperproliferation., Impact: This study presents Arginase inhibition as a new therapeutic target and the importance of the combined antenatal treatment to improve pulmonary vascular development in a congenital diaphragmatic hernia (CDH) rat model. This study shows that the action of an Arginase inhibitor (ABH) enhances the effects already described for sildenafil in this model. These results reinforce the importance of prenatal treatments' synergy in recovering the hypoplastic lung in the Nitrofen-induced CDH rat model., (© 2022. The Author(s), under exclusive licence to the International Pediatric Research Foundation, Inc.)

The known oxygenated polyhalogenated diphenyl ether, 2-(2',4'-dibromophenoxy)-3,5-dibromophenol ( 1 ), with previously reported activity in multiple cytotoxicity assays was isolated from the sponge Lamellodysidea sp. and proved to be an amenable scaffold for semisynthetic library generation. The phenol group of 1 was targeted to generate 12 ether analogues in low-to-excellent yields, and the new library was fully characterized by NMR, UV, and MS analyses. The chemical structures for 2 , 8 , and 9 were additionally determined via single-crystal X-ray diffraction analysis. All natural and semisynthetic compounds were evaluated for their ability to inhibit the growth of DU145, LNCaP, MCF-7, and MDA-MB-231 cancer cell lines. Compound 3 was shown to have near-equivalent activity compared to scaffold 1 in two in vitro assays, and the activity of the compounds with an additional benzyl ring appeared to be reliant on the presence and position of additional halogens.

Sodium-calcium exchanger proteins influence calcium homeostasis in many cell types and participate in a wide range of physiological and pathological processes. Here, we elucidate the cryo-EM structure of the human Na + /Ca 2+ exchanger NCX1.3 in the presence of a specific inhibitor, SEA0400. Conserved ion-coordinating residues are exposed on the cytoplasmic face of NCX1.3, indicating that the observed structure is stabilized in an inward-facing conformation. We show how regulatory calcium-binding domains (CBDs) assemble with the ion-translocation transmembrane domain (TMD). The exchanger-inhibitory peptide (XIP) is trapped within a groove between the TMD and CBD2 and predicted to clash with gating helices TMs 1/6 at the outward-facing state, thus hindering conformational transition and promoting inactivation of the transporter. A bound SEA0400 molecule stiffens helix TM2ab and affects conformational rearrangements of TM2ab that are associated with the ion-exchange reaction, thus allosterically attenuating Ca 2+ -uptake activity of NCX1.3., (© 2023. The Author(s).)

Bifenox is a widely used herbicide that contains a diphenyl ether group. However its global usage, the cell physiological effects that induce toxicity have not been elucidated. In this study, the effect of bifenox was examined in porcine trophectoderm and uterine epithelial cells to investigate the potential toxicity of the implantation process. To uncover the toxic effects of bifenox, cell viability and apoptosis following treatment with bifenox were evaluated. To investigate the underlying cellular mechanisms, mitochondrial and calcium homeostasis were investigated in both cell lines. In addition, the dysregulation of cell signal transduction and transcriptional alterations were also demonstrated. Bifenox reduced cell viability and significantly increased the number of cells arrested at the sub-G1 stage. Moreover, bifenox depolarized the mitochondrial membrane and upregulated the calcium flux into the mitochondria in both cell lines. Cytosolic calcium flux increased in porcine trophectoderm (pTr) cells and decreased in porcine luminal epithelium (pLE) cells. In addition, bifenox activated the mitogen-activated protein kinase and phosphoinositide 3-kinase signaling pathways. Furthermore, bifenox inhibited the expression of retinoid receptor genes, such as RXRA, RXRB, and RXRG. Chemokine CCL8 was also downregulated at the mRNA level, whereas CCL5 expression remained unchanged. Overall, the results of this study suggest that bifenox deteriorates cell viability by arresting cell cycle progression, damaging mitochondria, and controlling calcium levels in pTr and pLE cells. The present study indicates the toxic potential of bifenox in the trophectoderm and luminal epithelial cells, which can lead to implantation disorders in early pregnancy., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

In the eye, the isomerization of all- trans -retinal to 11- cis -retinal is accomplished by a metabolic pathway termed the visual cycle that is critical for vision. RPE65 is the essential trans - cis isomerase of this pathway. Emixustat, a retinoid-mimetic RPE65 inhibitor, was developed as a therapeutic visual cycle modulator and used for the treatment of retinopathies. However, pharmacokinetic liabilities limit its further development including: (1) metabolic deamination of the γ-amino-α-aryl alcohol, which mediates targeted RPE65 inhibition, and (2) unwanted long-lasting RPE65 inhibition. We sought to address these issues by more broadly defining the structure-activity relationships of the RPE65 recognition motif via the synthesis of a family of novel derivatives, which were tested in vitro and in vivo for RPE65 inhibition. We identified a potent secondary amine derivative with resistance to deamination and preserved RPE65 inhibitory activity. Our data provide insights into activity-preserving modifications of the emixustat molecule that can be employed to tune its pharmacological properties.

Quinazoline derivatives have various pharmacological activities and are widely used in clinical practice. Here, we reviewed the proposed mechanisms of the physiological activity of the quinazoline derivative EVP4593 and perspectives for its clinical implication. We summarized the accumulated data about EVP4593 and focused on its activities in different models of Huntington's disease (HD), including patient-specific iPSCs-based neurons. To make a deeper insight into its neuroprotective role in HD treatment, we discussed the ability of EVP4593 to modulate calcium signaling and reduce the level of the huntingtin protein. Moreover, we described possible protective effects of EVP4593 in other pathologies, such as oncology, cardiovascular diseases and parasite invasion. We hope that comprehensive analyses of the molecular mechanisms of EVP4593 activity will allow for the expansion of the scope of the EVP4593 application.

Four new diphenyl ether derivatives, neopestolides A-D ( 2 - 5 ), were isolated from cultures of the plant endophytic fungus Neopestalotiopsis sp., along with the known metabolite pestalotiollide A ( 1 ); their structures were elucidated primarily by NMR experiments. The absolute configurations of 2 and 3 - 5 were deduced by electronic circular dichroism calculations and via Snatzke's method, respectively. Compounds 2 - 4 incorporate tetrahydrofuran moieties attached to the dibenzo[b,g][1,5]dioxocin-5(7 H )-one skeleton via C-C linkages. Compounds 1 and 2 showed modest cytotoxicity against HepG2 cells.

The development of small-molecules targeting different components of SARS-CoV-2 is a key strategy to complement antibody-based treatments and vaccination campaigns in managing the COVID-19 pandemic. Here, we show that two thiol-based chemical probes that act as reducing agents, P2119 and P2165, inhibit infection by human coronaviruses, including SARS-CoV-2, and decrease the binding of spike glycoprotein to its receptor, the angiotensin-converting enzyme 2 (ACE2). Proteomics and reactive cysteine profiling link the antiviral activity to the reduction of key disulfides, specifically by disruption of the Cys379-Cys432 and Cys391-Cys525 pairs distal to the receptor binding motif in the receptor binding domain (RBD) of the spike glycoprotein. Computational analyses provide insight into conformation changes that occur when these disulfides break or form, consistent with an allosteric role, and indicate that P2119/P2165 target a conserved hydrophobic binding pocket in the RBD with the benzyl thiol-reducing moiety pointed directly toward Cys432. These collective findings establish the vulnerability of human coronaviruses to thiol-based chemical probes and lay the groundwork for developing compounds of this class, as a strategy to inhibit the SARS-CoV-2 infection by shifting the spike glycoprotein redox scaffold., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)

Transient receptor potential canonical 3 (TRPC3) is a nonselective cation channel, and its dysfunction is the basis of many clinical diseases. However, little is known about its possible role in the bladder. The purpose of this study was to explore the function and mechanism of TRPC3 in partial bladder outlet obstruction (PBOO)-induced detrusor overactivity (DO). We studied 31 adult female rats with DO induced by PBOO (the DO group) and 40 sham-operated rats (the control group). Here we report that the expression of TRPC3 in the bladder of DO rats increased significantly. Furthermore, PYR10, which can selectively inhibit the TRPC3 channel, significantly reduced bladder excitability in DO and control rats, but the decrease of the bladder excitability of DO rats was more obvious. PYR10 significantly reduced the intracellular calcium concentration in smooth muscle cells (SMCs) in DO and control rats. Finally, Na + /Ca 2+ exchanger 1 (NCX1) colocalizes with TRPC3 and affects its expression and function. Collectively, these results indicate that TRPC3 plays an important role in the pathogenesis of DO through a synergistic effect with NCX1. TRPC3 and NCX1 may be new therapeutic targets for DO., (© 2021. The Author(s), under exclusive licence to United States and Canadian Academy of Pathology.)

Three analogues of To042, a tocainide-related lead compound recently reported for the treatment of myotonia, were synthesized and evaluated in vitro as skeletal muscle sodium channel blockers possibly endowed with enhanced use-dependent behavior. Patch-clamp experiments on hNav1.4 expressed in HEK293 cells showed that N-[(naphthalen-1-yl)methyl]-4-[(2,6-dimethyl)phenoxy]butan-2-amine, the aryloxyalkyl bioisostere of To042, exerted a higher use-dependent block than To042 thus being able to preferentially block the channels in over-excited membranes while preserving healthy tissue function. It also showed the lowest active transport across BBB according to the results of P-glycoprotein (P-gp) interacting activity evaluation and the highest cytoprotective effect on HeLa cells. Quantum mechanical calculations and dockings gave insights on the most probable conformation of the aryloxyalkyl bioisostere of To042 in solution and the target residues involved in the binding, respectively. Both approaches indicated the conformations that might be adopted in both the unbound and bound state of the ligand. Overall, N-[(naphthalen-1-yl)methyl]-4-[(2,6-dimethyl)phenoxy]butan-2-amine exhibits an interesting toxico-pharmacological profile and deserves further investigation., (© 2021 The Authors. ChemMedChem published by Wiley-VCH GmbH.)

The pathogenicity of HCC could be enhanced by TNF-α and NFκB, which are crucial parts of the inflammatory pathway inside the HCC microenvironment. Therefore, we aimed to discover the therapeutic effects of QNZ, an inhibitor of both TNF-α and NFκB, in an experimental model of HCC in rats. HCC was experimentally induced in rats by thioacetamide, and some of the rats were treated with QNZ. The expression levels of nuclear factor (NF)κB, tumor necrosis factor (TNF)-α, apoptosis signal regulating kinase (ASK)-1, β-catenin, glycogen synthase kinase (GSK)-3 and TNF receptor-associated factor (TRAF) were examined in hepatic samples. In addition, hepatic tissues were stained with hematoxylin/eosin and anti-TNF-α antibodies. QNZ blocked HCC-induced expression of both NFκB and TNF-α. It significantly reduced both α-fetoprotein and the average number of nodules and increased the survival rate of the HCC rats. Moreover, hematoxylin and eosin liver sections from the HCC rats showed vacuolated cytoplasm and necrotic nodules. All of these effects were alleviated by QNZ treatment. Finally, treating HCC rats with QNZ resulted in a reduction in the expression of TRAF, ASK-1 and β-catenin, as well as increased expression of GSK-3. In conclusion, inhibition of the inflammatory pathway in HCC with QNZ produced therapeutic effects, as indicated by an increased survival rate, reduced serum α-fetoprotein levels, decreased liver nodules and improved the hepatocyte structure. In addition, QNZ significantly reduced the expression of TRAF, ASK-1 and β-catenin that were associated with increased expression of GSK-3., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The strategy "IEMAHC" (Induction of Endophyte Metabolism by Adding Host Components) was applied to the fermentation of the endophytic fungus Epicoccum sorghinum L28 from Myoporum bontioides by introducing guaiol, an ingredient of M. bontioides, into the cultivation medium, which resulted in the purification of nine new diphenyl ethers, epicoccethers A-I (1-9). Their structures were determined by overall spectroscopic analysis. HPLC-MS analysis revealed that compounds 5-7 were products generated by induction of guaiol. Compounds 6 and 7 are the first members containing an ester moiety formed by the natural long-chain fatty acid and the hydroxyl group in the phenylmethanol unit of the diphenyl ether class. The antifungal activities of compounds 1, 2, and 4-7 against Fusarium oxysporum were 1, 1, 2, 1, 2 and 4 times as high as those of the positive control triadimefon, respectively. Compounds 4 and 5 showed 1.6 times the antifungal activities of triadimefon towards Colletotrichum musae., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Oxidative stress plays a pathological role in pulmonary hypoplasia and pulmonary hypertension in congenital diaphragmatic hernia (CDH). This study investigated the effect of molecular hydrogen (H 2 ), an antioxidant, on CDH pathology induced by nitrofen. Sprague-Dawley rats were divided into three groups: control, CDH, and CDH + hydrogen-rich water (HW). Pregnant dams of CDH + HW pups were orally administered HW from embryonic day 10 until parturition. Gasometric evaluation and histological, immunohistochemical, and real-time polymerase chain reaction analyses were performed. Gasometric results (pH, pO 2, and pCO 2 levels) were better in the CDH + HW group than in the CDH group. The CDH + HW group showed amelioration of alveolarization and pulmonary artery remodeling compared with the CDH group. Oxidative stress (8-hydroxy-2'-deoxyguanosine-positive-cell score) in the pulmonary arteries and mRNA levels of protein-containing pulmonary surfactant that protects against pulmonary collapse (surfactant protein A) were significantly attenuated in the CDH + HW group compared with the CDH group. Overall, prenatal H 2 administration improved respiratory function by attenuating lung morphology and pulmonary artery thickening in CDH rat models. Thus, H 2 administration in pregnant women with diagnosed fetal CDH might be a novel antenatal intervention strategy to reduce newborn mortality due to CDH.

Previously unreported anthraquinone, acetylpenipurdin A ( 4 ), biphenyl ether, neospinosic acid ( 6 ), dibenzodioxepinone, and spinolactone ( 7 ) were isolated, together with ( R )-6-hydroxymellein ( 1 ), penipurdin A ( 2 ), acetylquestinol ( 3 ), tenellic acid C ( 5 ), and vermixocin A ( 8 ) from the culture of a marine sponge-associated fungus Neosartorya spinosa KUFA1047. The structures of the previously unreported compounds were established based on an extensive analysis of 1D and 2D NMR spectra as well as HRMS data. The absolute configurations of the stereogenic centers of 5 and 7 were established unambiguously by comparing their calculated and experimental electronic circular dichroism (ECD) spectra. Compounds 2 and 5 - 8 were tested for their in vitro acetylcholinesterase and tyrosinase inhibitory activities as well as their antibacterial activity against Gram-positive and Gram-negative reference, and multidrug-resistant strains isolated from the environment. The tested compounds were also evaluated for their capacity to inhibit biofilm formation in the reference strains.

Invasive breast cancer (BrCa) is predicted to affect 1 in 9 women in a lifetime;1 in 32 will die from this disease. The most aggressive forms of BrCa, basal-like/triple-negative phenotype (TNBC), are challenging to treat and result in higher mortality due high number of metastatic cases. There is a paucity of options for TNBC treatment, which highlights the need for additional innovative treatment approaches. NIH-III mice were injected in the abdominal mammary fat pad with luciferase-expressing derivative of the human TNBC cell line, MDA-MB-231 cells. Animals were gavage-fed with nitrofen at the doses of 1, 3 or 6 mg/kg/alternate days. However, several structural properties/components of nitrofen raise concerns, including its high lipophilicity (cLogP of nearly 5) and a potential toxophore in the form of a nitroarene group. Therefore, we developed analogues of nitrofen which lack the nitro group and/or have replaced the diaryl ether linker with a diarylamine that could allow modulation of polarity. In vitro anti-invasiveness activity of nitrofen analogues were evaluated by quantitative determination of invasion of MDA-MB-231-Luciferase cells through Matrigel using a Boyden chamber. Our in vivo data show that nitrofen efficiently blocks TNBC tumor metastasis. In vitro data suggest that this is not due to cytotoxicity, but rather is due to impairment of invasive capacity of the cells. Further, using an in vitro model of EMT, we show that nitrofen interferes with the process of EMT and promotes mesenchymal to epithelial transformation. In addition, we show that three of the nitrofen analogues significantly reduced invasive potential of TNBC cells, which may, at least partially, be attributed to the analogues' ability to promote mesenchymal to epithelial-like transformation of TNBC cells. Our study shows that nitrofen, and more importantly its analogues, are significantly effective in limiting the invasive potential of TNBC cell lines with minimal cytotoxic effect. Further, we demonstrate that nitrofen its analogues, are very effective in reversing mesenchymal phenotype to a more epithelial-like phenotype. This may be significant for the treatment of patients with mesenchymal-TNBC tumor subtype who are well known to exhibit high resistance to chemotherapy.

Background: Chagas disease (CD) is a neglected disease that induces heart failure and arrhythmias in approximately 30% of patients during the chronic phase of the disease. Despite major efforts to understand the cellular pathophysiology of CD there are still relevant open questions to be addressed. In the present investigation we aimed to evaluate the contribution of the Na+/Ca2+ exchanger (NCX) in the electrical remodeling of isolated cardiomyocytes from an experimental murine model of chronic CD., Methodology/principal Findings: Male C57BL/6 mice were infected with Colombian strain of Trypanosoma cruzi. Experiments were conducted in isolated left ventricular cardiomyocytes from mice 180-200 days post-infection and with age-matched controls. Whole-cell patch-clamp technique was used to measure cellular excitability and Real-time PCR for parasite detection. In current-clamp experiments, we found that action potential (AP) repolarization was prolonged in cardiomyocytes from chagasic mice paced at 0.2 and 1 Hz. After-depolarizations, both subthreshold and with spontaneous APs events, were more evident in the chronic phase of experimental CD. In voltage-clamp experiments, pause-induced spontaneous activity with the presence of diastolic transient inward current was enhanced in chagasic cardiomyocytes. AP waveform disturbances and diastolic transient inward current were largely attenuated in chagasic cardiomyocytes exposed to Ni2+ or SEA0400., Conclusions/significance: The present study is the first to describe NCX as a cellular arrhythmogenic substrate in chagasic cardiomyocytes. Our data suggest that NCX could be relevant to further understanding of arrhythmogenesis in the chronic phase of experimental CD and blocking NCX may be a new therapeutic strategy to treat arrhythmias in this condition., Competing Interests: The authors have declared that no competing interests exist.

Farnesoid X receptor (FXR) agonist obeticholic acid (OCA) has emerged as a potential therapy for nonalcoholic fatty liver disease (NAFLD). However, the side effects of OCA may limit its application in clinics. We identified previously that isotschimgine (ITG) is a non-steroidal FXR selective agonist and has potent therapeutic effects on NAFLD in mice. Here, we aimed to evaluate the therapeutic effects of ITG on nonalcoholic steatohepatitis (NASH) and fibrosis in mice. We used methionine and choline deficient (MCD) diet-induced NASH mice, bile duct ligation (BDL), and carbon tetrachloride (CCl 4 )-treated hepatic fibrosis mice to investigate the effects of ITG on NASH, fibrosis, and cholestatic liver injury. Our results showed that ITG improved steatosis and inflammation in the liver of MCD diet-fed mice, as well as alleviated fibrosis and inflammation in the liver of CCl 4 -treated mice. Furthermore, ITG attenuated serum bile acid levels, and reduced vacuolization, inflammatory infiltration, hepatic parenchymal necrosis, and collagen accumulation in the liver of BDL mice. Mechanistically, ITG increased the expression of FXR target genes. These data suggest that ITG is an FXR agonist and may be developed as a novel therapy for NASH, hepatic fibrosis, or primary biliary cholangitis., (© 2021 John Wiley & Sons, Ltd.)

Programmed death protein 1 (PD-1)/programmed death protein ligand 1 (PD-L1) pathway is one of the most actively pursued targets in cancer immunotherapy. In a continuation of our research interest in this pathway, we synthesized and evaluated the pharmacological activities of a series of resorcinol biphenyl ether analogs as small molecule PD-1/PD-L1 inhibitors for cancer treatment. Among the 27 newly synthesized compounds, CH1 was found to have the highest inhibitory effect against PD-1/PDL-1 with an IC 50 value of 56.58 nM in the HTRF (homogenous time-resolved fluorescence) assay. In addition, CH1 dose-dependently promoted HepG2 cell death in a co-culture model of HepG2/hPD-L1 and Jurkat T cells. Furthermore, molecular modeling study indicated that CH1 binds with high affinity to the binding interface of PD-L1. Moreover, CH1 effectively inhibited tumor growth (TGI of 76.4% at 90 mg/kg) in an immune checkpoint humanized mouse model with no obvious toxicity. Finally, CH1 did not cause in vivo cardiotoxicity and bone marrow suppression (myelosuppression) to BALB/c mice. Taken together, these results suggest that CH1 deserves further investigation as a potent and safe PD-1/PDL-1 inhibitor for cancer treatment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Small-molecule mediated modulation of protein interactions of Bcl-2 (B-cell lymphoma-2) family proteins was clinically validated in 2015 when Venetoclax, a selective inhibitor of the antiapoptotic protein BCL-2, achieved breakthrough status designation by the FDA for treatment of lymphoid malignancies. Since then, substantial progress has been made in identifying inhibitors of other interactions of antiapoptosis proteins. However, targeting their pro-apoptotic counterparts, the "executioners" BAX, BAK, and BOK that both initiate and commit the cell to dying, has lagged behind. However, recent publications demonstrate that these proteins can be positively or negatively regulated using small molecule tool compounds. The results obtained with these molecules suggest that pharmaceutical regulation of apoptosis will have broad implications that extend beyond activating cell death in cancer. We review recent advances in identifying compounds and their utility in the exogenous control of life and death by regulating executioner proteins, with emphasis on the prototype BAX.

The research on bioactive secondary metabolites from Aspergillus fumigatus afforded six compounds, which were identified by mass spectrometer (MS) and nuclear magnetic resonance (NMR) spectroscopic analysis as cyclopyazonic acid (1), trypacidin A (2), asterric acid (3), methyl asterrate (4), demethylcitreoviranol (5), as well as (5-hydroxy-2-oxo-2H-pyran-4-yl) methyl acetate (6). Cyclopyazonic acid (1) was found to have potent antibacterial effects, especially against Bacillus licheniformis with minimal inhibitory concentration (MIC) value of 3.7μg/mL. Its antibacterial effects were possibly related to the olefinic acid group in the structure. Phenyl ether derivatives 3 and 4, and trypacidin A (2) also exhibited antimicrobial effects. In addition, compound 6 showed significant antioxidant effects with half maximal effective concentration (EC 50 ) value of 10.2μM in the ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) assay, which was better than the positive control.

We developed a method to evaluate the activity of the Na + -Ca 2+ exchanger (NCX) and sarco-endoplasmic reticulum Ca 2+ -ATPase (SERCA) with fluorescence microscopy in mouse ventricular cardiomyocytes. In non-beating ventricular cardiomyocytes, α-adrenoceptor stimulation by phenylephrine caused a decrease in the cytoplasmic Ca 2+ concentration, which was inhibited by SEA0400, an NCX inhibitor, but not cyclopiazonic acid, a SERCA inhibitor. β-Adrenoceptor stimulation by isoprenaline caused a decrease in the cytoplasmic Ca 2+ concentration, which was inhibited by cyclopiazonic acid but not SEA0400. Ellagic acid, a phenolic phytochemical, also decreased the basal Ca 2+ concentration, which was inhibited by cyclopiazonic acid, but not SEA0400. Thus, this method using fluorescent microscopy and specific inhibitors would be useful for the evaluation of pharmacological agents acting on NCX and SERCA.

Aims: Heart failure is a major complication in cancer treatment due to the cardiotoxic effects of anticancer drugs, especially from the anthracyclines such as doxorubicin (DXR). DXR enhances oxidative stress and stimulates matrix metalloproteinase-2 (MMP-2) in cardiomyocytes. We investigated whether MMP inhibitors protect against DXR cardiotoxicity given the role of MMP-2 in proteolyzing sarcomeric proteins in the heart and remodelling the extracellular matrix., Methods and Results: Eight-week-old male C57BL/6J mice were treated with DXR weekly with or without MMP inhibitors doxycycline or ONO-4817 by daily oral gavage for 4 weeks. Echocardiography was used to determine cardiac function and left ventricular remodelling before and after treatment. MMP inhibitors ameliorated DXR-induced systolic and diastolic dysfunction by reducing the loss in left ventricular ejection fraction, fractional shortening, and E'/A'. MMP inhibitors attenuated adverse left ventricular remodelling, reduced cardiomyocyte dropout, and prevented myocardial fibrosis. DXR increased myocardial MMP-2 activity in part also by upregulating N-terminal truncated MMP-2. Immunogold transmission electron microscopy showed that DXR elevated MMP-2 levels within the sarcomere and mitochondria which were associated with myofilament lysis, mitochondrial degeneration, and T-tubule distention. DXR-induced myofilament lysis was associated with increased titin proteolysis in the heart which was prevented by ONO-4817. DXR also increased the level and activity of MMP-2 in human embryonic stem cell-derived cardiomyocytes, which was reduced by ONO-4817., Conclusions: MMP-2 activation is an early event in DXR cardiotoxicity and contributes to myofilament lysis by proteolyzing cardiac titin. Two orally available MMP inhibitors ameliorated DXR cardiotoxicity by attenuating intracellular and extracellular matrix remodelling, suggesting their use may be a potential prophylactic strategy to prevent heart injury during chemotherapy., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)

The lusitropic effect of quercetin was examined on isolated ventricular myocardial tissue preparations from normal and streptozotocin-induced diabetic mice. The time required for 90% relaxation of the myocardium, which was prolonged in the diabetic mice, was shortened by quercetin in both normal and diabetic myocardia. This effect of quercetin was completely inhibited by cyclopiazonic acid but not by SEA0400. These results indicated that quercetin accelerates myocardial relaxation through activation of the sarco-endoplasmic reticulum Ca 2+ -ATPase.

Voltage-gated sodium channels (Navs) are promising targets for analgesic and antiepileptic therapies. Although specificity between Nav subtypes may be desirable to target specific neural types, such as nociceptors in pain, many broadly acting Nav inhibitors are clinically beneficial in neuropathic pain and epilepsy. Here, we present the first systematic characterization of vixotrigine, a Nav blocker. Using recombinant systems, we find that vixotrigine potency is enhanced in a voltage- and use-dependent manner, consistent with a state-dependent block of Navs. Furthermore, we find that vixotrigine potently inhibits sodium currents produced by both peripheral and central nervous system Nav subtypes, with use-dependent IC 50 values between 1.76 and 5.12 μM. Compared with carbamazepine, vixotrigine shows higher potency and more profound state-dependent inhibition but a similar broad spectrum of action distinct from Nav1.7- and Nav1.8-specific blockers. We find that vixotrigine rapidly inhibits Navs and prolongs recovery from the fast-inactivated state. In native rodent dorsal root ganglion sodium channels, we find that vixotrigine shifts steady-state inactivation curves. Based on these results, we conclude that vixotrigine is a broad-spectrum, state-dependent Nav blocker. SIGNIFICANCE STATEMENT: Vixotrigine blocks both peripheral and central voltage-gated sodium channel subtypes. Neurophysiological approaches in recombinant systems and sensory neurons suggest this block is state-dependent., Competing Interests: C. Hinckley, M. Hajos, and H. Naik are/were employees of and own stock/stock options in Biogen. Y. Kuryshev, A. Sers, A. Barre, and B. Buisson have no conflicts of interest to declare., (Copyright © 2020 by The Author(s).)

The pyrazole-4-carboxamide scaffold containing a flexible amide chain has emerged as the molecular skeleton of highly efficient agricultural fungicides targeting succinate dehydrogenase (SDH). Based on the above vital structural features of succinate dehydrogenase inhibitors (SDHI), three types of novel pyrazole-4-formylhydrazine derivatives bearing a diphenyl ether moiety were rationally conceived under the guidance of a virtual docking comparison between bioactive molecules and SDH. Consistent with the virtual verification results of a molecular docking comparison, the in vitro antifungal bioassays indicated that the skeleton structure of title compounds should be optimized as an N '-(4-phenoxyphenyl)-1 H -pyrazole-4-carbohydrazide scaffold. Strikingly, N '-(4-phenoxyphenyl)-1 H -pyrazole-4-carbohydrazide derivatives 11o against Rhizoctonia solani , 11m against Fusarium graminearum , and 11g against Botrytis cinerea exhibited excellent antifungal effects, with corresponding EC 50 values of 0.14, 0.27, and 0.52 μg/mL, which were obviously better than carbendazim against R. solani (0.34 μg/mL) and F. graminearum (0.57 μg/mL) as well as penthiopyrad against B. cinerea (0.83 μg/mL). The relative studies on an in vivo bioassay against R. solani , bioactive evaluation against SDH, and molecular docking were further explored to ascertain the practical value of compound 11o as a potential fungicide targeting SDH. The present work provided a non-negligible complement for the structural optimization of antifungal leads targeting SDH.

In the present work, the anti-inflammatory and antiasthmatic potential of biseugenol, isolated as the main component from n -hexane extract from leaves of Nectandra leucantha and chemically prepared using oxidative coupling from eugenol, was evaluated in an experimental model of mixed-granulocytic asthma. Initially, in silico studies of biseugenol showed good predictions for drug-likeness, with adherence to Lipinski's rules of five (RO5), good Absorption, Distribution, Metabolism and Excretion (ADME) properties and no alerts for Pan-Assay Interference Compounds (PAINS), indicating adequate adherence to perform in vivo assays. Biseugenol (20 mg·kg -1 ) was thus administered intraperitoneally (four days of treatment) and resulted in a significant reduction in both eosinophils and neutrophils of bronchoalveolar lavage fluid in ovalbumin-sensitized mice with no statistical difference from dexamethasone (5 mg·kg -1 ). As for lung function parameters, biseugenol (20 mg·kg -1 ) significantly reduced airway and tissue damping in comparison to ovalbumin group, with similar efficacy to positive control dexamethasone. Airway hyperresponsiveness to intravenous methacholine was reduced with biseugenol but was inferior to dexamethasone in higher doses. In conclusion, biseugenol displayed antiasthmatic effects, as observed through the reduction of inflammation and airway hyperresponsiveness, with similar effects to dexamethasone, on mixed-granulocytic ovalbumin-sensitized mice.

Diphenyl ether derivatives inhibit mycobacterial cell wall synthesis by inhibiting an enzyme, enoyl-acyl carrier protein reductase (InhA), which catalyses the last step in the fatty acid synthesis cycle of genus Mycobacterium. To select and validate a protein crystal structure of enoyl-acyl carrier protein reductase of Mycobacterium tuberculosis for designing inhibitors using molecular modelling, a cross-docking and correlation study was performed. A series of novel 1-(3-(3-hydroxy-4-phenoxyphenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl) ethan-1-ones were synthesized from this model and screened for their antitubercular activity against M. tuberculosis H37Rv. Compound PYN-8 showed good antitubercular activity on M. tuberculosis H37Rv (MIC = 4-7 µM) and Mycobacterium bovis (% inhibition at 10 µM = 95.91%). Cytotoxicity of all the synthesized derivatives was assessed using various cell lines, and they were found to be safe. Structure of PYN-8 was also confirmed by single-crystal X-ray diffraction. The molecular modelling studies also corroborated the biological activity of the compounds. Further, in silico findings revealed that all these tested compounds exhibited good ADME properties and drug likeness and thus may be considered as potential candidates for further drug development.

The discovery of how a photon is converted into a chemical signal is one of the most important achievements in the field of vision. A key molecule in this process is the visual chromophore retinal. Several eye diseases are attributed to the abnormal metabolism of retinal in the retina and the retinal pigment epithelium. Also, the accumulation of two toxic retinal derivatives, N-retinylidene-N-retinylethanolamine and the retinal dimer, can damage the retina leading to blindness. RPE65 (Retinal pigment epithelium-specific 65 kDa protein) is one of the central enzymes that regulates the metabolism of retinal and the formation of its toxic metabolites. Its inhibition might decrease the rate of the retina's degeneration by limiting the amount of retinal and its toxic byproducts. Two RPE65 inhibitors, (R)-emixustat and (R)-MB001, were recently developed for this purpose., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Novel small molecule compounds based on various scaffolds including chalcone, flavonoid, and resorcinol dibenzyl ether were designed and tested for their inhibitory activity against the Programmed Cell Death-1/Programmed Cell Death-Ligand 1 (PD-1/PD-L1) pathway. Among them, compound NP19 inhibited the human PD-1/PD-L1 interaction with IC 50 values of 12.5 nM in homogeneous time-resolved fluorescence (HTRF) binding assays. In addition, NP19 dose-dependently elevated IFN-γ production in a coculture model of Hep3B/OS-8/hPD-L1 and CD3 T cells. Furthermore, NP19 displayed significant in vivo antitumor efficacy in two different mouse models of cancer (a melanoma B16-F10 tumor model and an H22 hepatoma tumor model). Moreover, H&E staining and flow cytometry data suggested that NP19 activated the immune microenvironment in the tumor, which may contribute to its antitumor effects. This work shows NP19 is a promising lead compound for further development as a new generation of small molecule inhibitors targeting the PD-1/PD-L1 pathway.

Diorcinols and related prenylated diaryl ethers were reported to exhibit activity against methicillin-resistant clinical isolates of Staphylococcus aureus (MRSA). Within these lines, we report the first total synthesis of diorcinol D, I, J, the proposed structure of verticilatin and recently isolated antibacterial diaryl ether by using an efficient and highly divergent synthetic strategy. These total syntheses furnish the diaryl ethers in only five to seven steps employing a Pd-catalyzed diaryl ether coupling as the key step. The total synthesis led to the structural revision of the natural product verticilatin, which has been isolated from a plant pathogenic fungus. Furthermore, these structures were tested in order to determine their antibacterial activities against different MRSA strains as well as further Gram-positive and -negative bacteria., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Background and Objective: Vixotrigine is a voltage- and use-dependent sodium channel blocker in development for neuropathic pain management. This study evaluated the effect of coadministration of vixotrigine (metabolized primarily via uridine diphosphate-glucuronosyltransferases) and an oral contraceptive containing ethinyl estradiol (uridine diphosphate-glucuronosyltransferase inducer) and levonorgestrel on the pharmacokinetics and safety of all three compounds., Methods: In this phase I, open-label, fixed-sequence, multiple-dose study, 36 healthy women received oral vixotrigine 150 mg three times daily for 6 days and once on day 7. This was followed by a washout period, days 8-11. The oral contraceptive was administered alone on days 12-25 and with vixotrigine 150 mg three times daily on days 26-32. Serial blood samples were collected for pharmacokinetic analysis. Safety was assessed., Results: The geometric least-squares mean ratios (90% confidence intervals) for the area under the concentration-time curve over 8 h and maximum concentration of vixotrigine co-administered with an oral contraceptive vs vixotrigine alone were 0.85 (0.82-0.89) and 0.91 (0.87-0.96), respectively. The geometric least-squares mean ratios (90% confidence interval) for area under the concentration-time curve over 24 h and maximum concentration of ethinyl estradiol with vixotrigine vs ethinyl estradiol alone were 0.94 (0.91-0.97) and 0.89 (0.84-0.94), respectively; the ratios for levonorgestrel with vixotrigine vs levonorgestrel alone were 1.06 (0.98-1.16) and 1.05 (0.98-1.13), respectively. No adverse events occurring with vixotrigine alone were deemed related to the study drug by the investigators., Conclusions: Coadministration of vixotrigine and an oral contraceptive containing ethinyl estradiol and levonorgestrel had no clinically relevant effect on exposure of all three compounds., Trial Registration: ClinicalTrials.gov registration number: NCT03324685 (registered 25 October, 2017).

Novel resorcinol diphenyl ether-based PROTACs (PROteolysis TArgeting Chimeras) were designed and evaluated for their inhibitory activity against the programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) pathway and their ability to degrade PD-L1 protein. Most of the compounds displayed excellent inhibitory activities against PD-1/PD-L1, as assessed by the homogenous time-resolved fluorescence (HTRF) binding assay, with IC50 values ranging from 25 nM to 200 nM. Among them, compound P22 is one of the best with an IC50 value of 39.2 nM. In addition to inhibiting PD-1/PD-L1 interaction, P22 also significantly restored the immunity repressed in a co-culture model of Hep3B/OS-8/hPD-L1 and CD3 T cells. Furthermore, flow cytometry (FCM) and western-blot data demonstrated that P22 could moderately reduce the protein levels of PD-L1 in a lysosome-dependent manner, which may contribute to its immune effects. Preliminary FCM and western-blot data suggest that it is possible to build PD-L1-targeting PROTAC-like molecules based on PD-1/PD-L1 small molecule inhibitors, though these compounds showed only modest degradation efficiencies. Collectively, this work suggests that P22 may serve as a starting point for exploring the degradation of PD-L1 by PROTAC-like strategy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

The sodium (Na+)-chloride cotransporter (NCC) expressed in the distal convoluted tubule (DCT) is a key molecule regulating urinary Na+ and potassium (K+) excretion. We previously reported that high-K+ load rapidly dephosphorylated NCC and promoted urinary K+ excretion in mouse kidneys. This effect was inhibited by calcineurin (CaN) and calmodulin inhibitors. However, the detailed mechanism through which high-K+ signal results in CaN activation remains unknown. We used Flp-In NCC HEK293 cells and mice to evaluate NCC phosphorylation. We analyzed intracellular Ca2+ concentration ([Ca2+]in) using live cell Ca2+ imaging in HEK293 cells. We confirmed that high-K+-induced NCC dephosphorylation was not observed without CaN using Flp-In NCC HEK29 cells. Extracellular Ca2+ reduction with a Ca2+ chelator inhibited high-K+-induced increase in [Ca2+]in and NCC dephosphorylation. We focused on Na+/Ca2+ exchanger (NCX) 1, a bidirectional regulator of cytosolic Ca2+ expressed in DCT. We identified that NCX1 suppression with a specific inhibitor (SEA0400) or siRNA knockdown inhibited K+-induced increase in [Ca2+]in and NCC dephosphorylation. In a mouse study, SEA0400 treatment inhibited K+-induced NCC dephosphorylation. SEA0400 reduced urinary K+ excretion and induced hyperkalemia. Here, we identified NCX1 as a key molecule in urinary K+ excretion promoted by CaN activation and NCC dephosphorylation in response to K+ load., Competing Interests: The authors have declared that no competing interests exist.

Purpose: Extracellular accumulation of all-trans-retinaldehyde (atRAL), a highly reactive visual cycle intermediate, is toxic to cells of the outer retina and contributes to retinal and macular degenerations. However, the contribution of atRAL to retinal capillary function has not been studied. We hypothesized that atRAL released from the outer retina can contribute to retinal vascular permeability. We, therefore, tested the contribution of atRAL to retinal ischemia-reperfusion (IR)-induced vascular permeability., Methods: IR was induced in mice by transient increase in intraocular pressure followed by natural reperfusion. The visual cycle was ablated in the Lrat-/- mice, reduced by dark adaptation or the use of the RPE65 inhibitor and atRAL scavenger emixustat. Accumulation of FITC-BSA was used to assess vascular permeability and DNA fragmentation quantified cell death after IR. Primary bovine retinal endothelial cell (BREC) culture was used to measure the direct effects of atRAL on endothelial permeability and cell death., Results: Inhibition of the visual cycle by Lrat-/-, dark adaptation, or with emixustat, all reduced approximately half of IR induced vascular permeability at 48 hours. An increase in BREC permeability with atRAL coincided with lactate dehydrogenase (LDH) release, a measure of cell death. Both permeability and toxicity were blocked by emixustat., Conclusions: Outer retinal pathology may contribute to vascular permeability by release of atRAL, which can act directly on vascular endothelial cells to alter barrier properties and induce cell death. These studies may have implications for a variety of blinding eye diseases that include outer retinal damage and retinal vascular permeability.

The deubiquitinase otubain 2 (OTUB2) has been reported to play significant roles in the tumorigenesis of several cancers, but the role of OTUB2 in liver cancer is not investigated yet. In the present study, OTUB2 was found significantly upregulated in liver cancer tumor tissues and cell lines, and elevated OTUB2 indicated as a negative index for the overall survival of liver cancer patients. At the cellular level, knockdown of OTUB2 markedly inhibited liver cancer cell growth. Our further investigations revealed that knockdown of OTUB2 significantly suppressed NF-κB-driving luciferase activity, and markedly inhibited the phosphorylation of NF-κB p65 in liver cancer cells, which indicated that OTUB2 mediated liver cancer cell growth by regulating NF-κB signaling. Additionally, we found that liver cancer cell lines harboring higher OTUB2 expression were more sensitive to NF-κB inhibitors, and overexpression of OTUB2 could significantly reduce the antitumor effects of NF-κB inhibitors in liver cancer cells. This study indicated that OTUB2 could be a promising target for the treatment of liver cancer in the future., (© 2020 The Authors. The Kaohsiung Journal of Medical Sciences published by John Wiley & Sons Australia on behalf of Kaohsiung Medical University.)

PF-05089771 is an aryl sulfonamide Nav1.7 channel blocker that binds to the inactivated state of Nav1.7 channels with high affinity but binds only weakly to channels in the resting state. Such aryl sulfonamide Nav1.7 channel blockers bind to the extracellular surface of the S1-S4 voltage-sensor segment of homologous Domain 4, whose movement is associated with inactivation. This binding site is different from that of classic sodium channel inhibitors like lidocaine, which also bind with higher affinity to the inactivated state than the resting state but bind at a site within the pore of the channel. The common dependence on gating state with distinct binding sites raises the possibility that inhibition by aryl sulfonamides and by classic local anesthetics might show an interaction mediated by their mutual state dependence. We tested this possibility by examining the state-dependent inhibition by PF-05089771 and lidocaine of human Nav1.7 channels expressed in human embryonic kidney 293 cells. At -80 mV, where a small fraction of channels are in an inactivated state under drug-free conditions, inhibition by PF-05089771 was both enhanced and speeded in the presence of lidocaine. The results suggest that lidocaine binding to the channel enhances PF-05089771 inhibition by altering the equilibrium between resting states (with D4S4 in the inner position) and inactivated states (with D4S4 in the outer position). The gating state-mediated interaction between the compounds illustrates a principle applicable to many state-dependent agents. SIGNIFICANCE STATEMENT: The results show that lidocaine enhances the degree and rate of inhibition of Nav1.7 channels by the aryl sulfonamide compound PF-05089771, consistent with state-dependent binding by lidocaine increasing the fraction of channels presenting a high-affinity binding site for PF-05089771 and suggesting that combinations of agents targeted to the pore-region binding site of lidocaine and the external binding site of aryl sulfonamides may have synergistic actions., (Copyright © 2020 by The American Society for Pharmacology and Experimental Therapeutics.)

Objective: Glucose is not only an energy source but also raw material for proteoglycan biosynthesis of chondrocyte. The aim of the present study is to explore the role of QNZ in the progress of chondrocytes glucose uptake and investigate whether it will improve the chondrocytes degeneration through Glut4 activation., Patients and Methods: We isolated human chondrocytes from the cartilage by the patients who underwent total knee arthroplasty operations. Chondrocytes were pretreated with insulin or QNZ for 24 h. The uptake of glucose with stimulation, as well as the expression of Glut4, collagen II, aggrecan, MMP13, TNF-α, PCNA, and the p16 levels were determined by Western blot, quantitative reverse-transcription polymerase chain reaction (qPCR), or immunofluorescence., Results: Both insulin and QNZ stimuli to chondrocytes contributed to the expression of Glut4 and glucose uptake compared to the normal cells. Additionally, collagen II and aggrecan expression was detected to a significant increase, along with the reduced levels of MMP13 and TNF-α after exposed to QNZ. Moreover, QNZ protected chondrocytes degeneration via promoting proliferation and delaying aging. After blocking Glut4, the glucose uptake significantly reduced in QNZ treatment, as well as the expression of collagen II and aggrecan. However, no significant changes were noticed in the MMP13 and TNF-α levels., Conclusions: The present study demonstrates that inhibition of NF-κB activation by QNZ would improve the glucose uptake through Glut4 activation, which plays an important role in the protection of chondrocytes degeneration.

Insect-borne parasite Trypanosoma brucei plagues humans and other animals, eliciting the disease Human African trypanosomiasis, also known as African sleeping sickness. This disease poses the biggest threat to the people in Sub-Saharan Africa. Given the high toxicity and difficulties with administration of currently available drugs, a novel treatment is needed. Building on known Human African trypanosomiasis structure-activity relationship (SAR), we now describe a number of functionally simple diphenyl ether analogs which give low micromolar activity (IC 50  = 0.16-0.96 μM) against T. b. rhodesiense. The best compound shows favorable selectivity against the L6 cell line (SI = 750) and even greater selectivity (SI = 1200) against four human cell lines. The data herein provides direction for the ongoing optimization of antitrypanosomal diphenyl ethers., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A field experiment was set up to evaluate persistence behaviour of pyridalyl in tomato, cabbage and cultivated field soil over two consecutive seasons. An analytical method was developed to analyze pyridalyl residues in different matrices and duly validated, based on single laboratory method validation criteria. Pyridalyl residues were detected and quantified using a gas chromatograph equipped with an electron capture detector. The compound exhibited low persistence in tomato, cabbage and soil. A safe waiting period of 17-18 d after final insecticide application needs to be maintained before harvesting the crop. Both dietary and soil ecological risk were assessed and it was found that the harvested vegetables were toxicologically safe for consumption. However, there was concern about insecticidal toxicity against the algal population of soil which needs to be reconfirmed by further studies., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Six new obovatol trimeric neolignans, houpulignans A-F (1-6) were isolated from the leaves of Magnolia officinalis var. biloba. Their structures were determined on the basis of the interpretation of HRESIMS, NMR data, and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of neolignans derived from three units of obovatol bearing a rare 1,4-benzodioxepane moiety. Compound 3 possesses a benzodihydropyran ring, meanwhile three units of obovatol in 4-6 are connected by an alkyl chain. Compounds 1-3 inhibited NO production in LPS-stimulated RAW264.7 cells with IC 50 values of 8.01, 20.21, and 4.05 µM, respectively., Competing Interests: Declaration of Competing Interest The authors declared that there is no conflict of interest., (Copyright © 2020. Published by Elsevier Inc.)

Methyl and phenyl esters of 2',3'-PhABA and iso-2',3'-PhABA were prepared for the biological investigation and development of practical applications. These esters exhibited excellent activity in most plant growth inhibitory assays. And, three esters were more efficient than ABA in stomatal closure. The 2',3'-PhABA analogs and their methyl esters have good stability in hydrolysis assay, and the different lipid solubility and permeability of different esters may be one of the origins of their active selectivity for different plants and physiological processes. Furthermore, in the study of drought tolerance, all four esters had comparable activity to ABA. These results suggest that these esters were potent plant growth regulator (PGR) candidates for anti-drought. The finding that different esters have different selective bioactivity and biophysical properties indicates that these esters not only function as ABA-like PGRs but also have the possibility as potential selective pro-hormone. 2',3'-BenzoABA esters as PGR candidates with prolonged and selective bioactivity.