Design and synthesis of benzofuran- and naphthalene-fused thiazinones as antimycobacterial agents

Benzothiazinones (BTZs) have widely inspired medicinal chemistry and translational research due to their remarkable antitubercular potency and clinical potential. While most structure-activity relationship campaigns have largely focused on lateral chain modifications and substituents on the BTZ core, scaffold hopping strategies have been rarely investigated previously. In this work, we report the first example of ring expansion of the BTZ core toward benzofuran- and naphthalene-fused thiazinones. In vitro testing showed micromolar activity for both compounds, and molecular docking simulations provided insights into their reduced inhibitory capacity toward the enzymatic target (DprE1). Calculated electrochemical potentials revealed a lower susceptibility to reduction as opposed to BTZ drug candidates, in line with the mechanistic requirement for covalent binding.

The Influence of Chirality on the β-Amino-Acid Naphthalenediimides/G-Quadruplex DNA Interaction

G-quadruplexes (G4s) have been identified as a potential alternative chemotherapy target. A series of eight β-amino acid derived naphthalenediimides (NDI) were screened against a series of oncogenic G4 sequences: c-KIT1, h-TELO, and TBA. Three sets of enantiomers were investigated to further our understanding of the effect of point chirality on G4 stabilisation. Enantioselective binding behaviour was observed with both c-KIT1 and h-TELO. Docking studies using GNINA and UV-vis titrations were employed to better understand this selective binding behaviour.

Synthesis of novel naphthalene-chimonanthine scaffolds hybrids with potent antibacterial or antifungal activity

In this work, a total of 19 novel naphthalene hybrids with chimonanthine scaffolds were efficiently synthesised from indole-3-acetonitrile in good yields. The prepared compounds were evaluated for biological activity against Cryptococcus neoformans, Escherichia coli, Shigella spp, Candida albicans, Salmonella spp, and Staphylococcus aureus. The preliminary bioassays showed that most of the synthesised compounds exhibited significant antibacterial or antifungal activity. Notably, compound 8 showed potent activity against Cryptococcus neofonmans, Escherichia coli, Shigella spp, and Candida albicans than the positive control, all with the same MIC value of 3.53 µM. Compound 8 had a broad spectrum of antibacterial or antifungal activity, and will be studied further.

Alicyclic Ring Size Variation of 4-Phenyl-2-naphthoic Acid Derivatives as P2Y14 Receptor Antagonists

P2Y14 receptor (P2Y14R) is activated by extracellular UDP-glucose, a damage-associated molecular pattern that promotes inflammation in the kidney, lung, fat tissue, and elsewhere. Thus, selective P2Y14R antagonists are potentially useful for inflammatory and metabolic diseases. The piperidine ring size of potent, competitive P2Y14R antagonist (4-phenyl-2-naphthoic acid derivative) PPTN 1 was varied from 4- to 8-membered rings, with bridging/functional substitution. Conformationally and sterically modified isosteres included N-containing spirocyclic (6-9), fused (11-13), and bridged (14, 15) or large (16-20) ring systems, either saturated or containing alkene or hydroxy/methoxy groups. The alicyclic amines displayed structural preference. An α-hydroxyl group increased the affinity of 4-(4-((1R,5S,6r)-6-hydroxy-3-azabicyclo[3.1.1]heptan-6-yl)phenyl)-7-(4-(trifluoromethyl)phenyl)-2-naphthoic acid 15 (MRS4833) compared to 14 by 89-fold. 15 but not its double prodrug 50 reduced airway eosinophilia in a protease-mediated asthma model, and orally administered 15 and prodrugs reversed chronic neuropathic pain (mouse CCI model). Thus, we identified novel drug leads having in vivo efficacy.

Anti-migration and anti-invasion effects of LY-290181 on breast cancer cell lines through the inhibition of Twist1

Breast cancer has become the most common cancer among women worldwide. Among breast cancers, metastatic breast cancer is associated with the highest mortality rate. Twist1, one of the epithelial-mesenchymal transition-regulating transcription factors, is known to promote the intravasation of breast cancer cells into metastatic sites. Therefore, targeting Twist1 to develop anti-cancer drugs might be a valuable strategy. In this study, LY-290181 dose-dependently inhibited migration, invasion, and multicellular tumor spheroid invasion in breast cancer cell lines. These anti-cancer effects of LY-290181 were mediated through the down-regulation of Twist1 protein levels. LY-290181 inhibited extracellular signal-regulated kinase and c-Jun N-terminal kinase signaling pathways. Therefore, our findings suggest that LY-290181 may serve as a basis for future research and development of an anti-cancer agent targeting metastatic cancers. [BMB Reports 2023; 56(7): 410-415].

Optimization of the C2 substituents on the 1,4-bis(arylsulfonamido)naphthalene-N,N'-diacetic acid scaffold for better inhibition of Keap1-Nrf2 protein-protein interaction

Direct inhibition of the protein-protein interaction (PPI) between Kelch-like ECH-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor 2 (Nrf2) reduces the ubiquitination and subsequent degradation of Nrf2, leading to Nrf2 accumulation in the cytosol and the nuclear translocation of Nrf2. Once inside the nucleus, Nrf2 binds to and activates the expression of antioxidant response element (ARE) genes involved in redox homeostasis and detoxification. Herein, we report a series of 1,4-bis(arylsulfonamido)naphthalene-N,N'-diacetic acid analogs with varying C2 substituents to explore the structure-activity relationships at this position of the central naphthalene core. The Keap1-binding activities were first screened with a fluorescence polarization (FP) assay followed by further evaluation of the more potent compounds using a more sensitive time-resolved fluorescence energy transfer (TR-FRET) assay. It was found that compound 24a with C2-phthalimidopropyl group was the most potent in this series showing an IC50 of 2.5 nM in the TR-FRET assay with a Ki value in the subnanomolar range. Our docking study indicated that the C2-phthalimidopropyl group in compound 24a provided an extra hydrogen bonding interaction with the key residue Arg415 that may be responsible for the observed boost in binding affinity. In addition, compounds 12b, 15, and 24a were shown to activate the Nrf2 signaling pathway in NCM460D cells resulting in elevated mRNA levels of GSTM3, HMOX1 and NQO1 by 2.4-11.7 fold at 100 μM as compared to the vehicle control.

Biological evaluation of polycyclic chalcone based acrylamides in human MCF-7 and HeLa cancer cell lines

Breast and cervical cancer account for the majority of cancer-narrated fatalities among women worldwide, necessitating the development of novel, effective therapeutic ways to combat the disease. In this study, we synthesized 6-methoxy naphthalene and anthracene-based acrylamide chalcone (NBA and ABA) and evaluated its activity for cell multiplication inhibition against two cancer cell lines from humans such as MCF-7 (Human Breast) and HeLa (Cervical) by MTT assay. Physiochemical characterization, such as FT-IR and NMR analyses, validated the synthesized NBA and ABA. Both NBA and ABA have shown antiproliferative action against two cancer cell lines, each with IC50 values of 38.46 and 48.25 μg/mL for HeLa cells and 38.02 and 36.35 μg/mL for MCF-7 cell lines. The results suggest that these acrylamide chalcones for cancer therapy at the lowest concentration. NBA and ABA could prevent cervical and breast cancer in-vitro, and their anti-cancer activity was closely related to methoxy-substituted naphthalene, anthracene ring, α, β-unsaturated carbonyl and amide group. According to docking data, the NBA and ABA have dock scores ranging from -8.7 to -11.44 kcal/mol. The highest dock score for compound ABA was -11.58 kcal/mol and compound NBA was -10.77 kcal/mol with Braf (5VAM) binding site.

Concentration of Polycyclic Aromatic Hydrocarbons (PAHs) in Human Serum and Adipose Tissues and Stimulatory Effect of Naphthalene in Adipogenesis in 3T3-L1 Cells

Polycyclic aromatic hydrocarbons (PAHs) are one of the most prevalent classes of environmental pollutants. Some evidence shows that PAHs could be involved in human obesity. However, little is known about the distribution patterns of PAHs in human adipose tissue (AT) and the role of PAHs on adipogenesis/lipogenesis. The aims of this pilot study were to determine concentrations of 16 PAHs defined as high-priority pollutants in the plasma and adipose tissue of French and Polish bariatric patients, as well as their correlation with body mass index (BMI), plasma and AT adipokines expression levels. We finally investigated the role of naphthalene on cell proliferation, viability, and differentiation in 3T3-L1 preadipocytes. The concentration of most PAHs was similar in the three types of AT and it was significantly higher in AT as compared to plasma, suggesting bioaccumulation. Polish patients had higher PAH levels in AT than French ones. Only the concentration of naphthalene in AT was positively correlated with the BMI and serum or adipose chemerin, adiponectin and resistin expression, in French but not in Polish patients, who had significantly higher BMIs. Moreover, naphthalene exposure increased the cell proliferation of 3T3-L1 preadipocytes and lipogenesis, and increased the expression of genes involved in adipogenesis after cell differentiation. Taken together, PAHs and more particularly naphthalene could be an obesogenic molecule and increase the risk of obesity.

Synthesis and evaluation of naphthalene derivatives as potent STAT3 inhibitors and agents against triple-negative breast cancer growth and metastasis

PURPOSE

Triple-negative breast cancer (TNBC) represents the worst prognostic subtype of breast cancer and lacks targeted therapeutic drugs. Signal transducer and activator of transcription 3 (STAT3) is overexpressed and constitutively activated in TNBCs and associated with poor patient outcomes. However, no agents targeting STAT3 have been successfully developed and marketed. Selective Estrogen Receptor Modulators (SERMs) have been reported as potential inhibitors of the IL-6/STAT3 signaling pathway. Naphthalene compounds have good pharmacological activity and significant anti-cancer activity. In this study, we synthesized a new series of naphthalene derivatives with the general structure of SERM and evaluated their effects on TNBC and STAT3 signals.

METHODS

A new series of compounds based on the scaffold of SERMs and an amino group were designed and screened based on the structure-activity relationship by MTT assay. The binding activity of SMY002 to STAT3 was predicted and validated by docking and SPR. The STAT3 signaling target and anti-cancer effects of SMY002 were evaluated with three TNBC cell lines and the mice transplanted tumor model.

RESULTS

Among the compounds, SMY002 displayed the most potent activity, which could directly interact with STAT3 SH2-domain, and strongly inhibit the phosphorylation, dimerization, nuclear distribution, transcriptional activity, and target genes expression of STAT3. Furthermore, SMY002 markedly suppressed migration, invasion, survival, growth, and metastasis of TNBC cells in vitro and in vivo via down-regulating the expression of Cyclin D1 and MMP9.

CONCLUSIONS

SMY002 can significantly inhibit the growth and metastasis of TNBC cells by targeting the STAT3 signal.

Design, Synthesis and Biological Evaluation of Syn and Anti-like Double Warhead Quinolinones Bearing Dihydroxy Naphthalene Moiety as Epidermal Growth Factor Receptor Inhibitors with Potential Apoptotic Antiproliferative Action

Our investigation includes the synthesis of new naphthalene-bis-triazole-bis-quinolin-2(1H)-ones 4a−e and 7a−e via Cu-catalyzed [3 + 2] cycloadditions of 4-azidoquinolin-2(1H)-ones 3a−e with 1,5-/or 1,8-bis(prop-2-yn-1-yloxy)naphthalene (2) or (6). All structures of the obtained products have been confirmed with different spectroscopic analyses. Additionally, a mild and versatile method based on copper-catalyzed [3 + 2] cycloaddition (Meldal−Sharpless reaction) was developed to tether quinolinones to O-atoms of 1,5- or 1,8-dinaphthols. The triazolo linkers could be considered as anti and syn products, which are interesting precursors for functionalized epidermal growth factor receptor (EGFR) inhibitors with potential apoptotic antiproliferative action. The antiproliferative activities of the 4a−e and 7a−e were evaluated. Compounds 4a−e and 7a−e demonstrated strong antiproliferative activity against the four tested cancer cell lines, with mean GI50 ranging from 34 nM to 134 nM compared to the reference erlotinib, which had a GI50 of 33 nM. The most potent derivatives as antiproliferative agents, compounds 4a, 4b, and 7d, were investigated for their efficacy as EGFR inhibitors, with IC50 values ranging from 64 nM to 97 nM. Compounds 4a, 4b, and 7d demonstrated potent apoptotic effects via their effects on caspases 3, 8, 9, Cytochrome C, Bax, and Bcl2. Finally, docking studies show the relevance of the free amino group of the quinoline moiety for antiproliferative action via hydrogen bond formation with essential amino acids.

One novel naphthalene derivative and other constituents with anti-complementary activities from the aerial parts of Dracocephalum moldavica

One novel naphthalene derivative, 2-octa-2',4',6'-atriynenaphthalene (1), together with eighteen known compounds (2-19) were isolated from the aerial parts of Dracocephalum moldavica L. Compounds 2, 8, 10, 13, 15-17 and 19 were obtained from the family Lamiaceae for the first time, and compounds 11 and 18 were firstly identified from the genus of Dracocephalum. All the isolates were evaluated for anti-complementary activities through the classical and alternative pathways, and the targets of the most active compounds on the complement activation cascade were also investigated.

1,3,4-Oxadiazole-naphthalene hybrids as potential VEGFR-2 inhibitors: design, synthesis, antiproliferative activity, apoptotic effect, and in silico studies

In the current work, some 1,3,4-oxadiazole-naphthalene hybrids were designed and synthesised as VEGFR-2 inhibitors. The synthesised compounds were evaluated in vitro for their antiproliferative activity against two human cancer cell lines namely, HepG-2 and MCF-7. Compounds that exhibited promising cytotoxicity (5, 8, 15, 16, 17, and 18) were further evaluated for their VEGFR-2 inhibitory activities. Compound 5 showed good antiproliferative activity against both cell lines and inhibitory effect on VEGFR-2. Besides, it induced apoptosis by 22.86% compared to 0.51% in the control (HepG2) cells. This apoptotic effect was supported by a 5.61-fold increase in the level of caspase-3 compared to the control cells. Moreover, it arrested the HepG2 cell growth mostly at the Pre-G1 phase. Several in silico studies were performed including docking, ADMET, and toxicity studies to predict binding mode against VEGFR-2 and to anticipate pharmacokinetic, drug-likeness, and toxicity of the synthesised compounds.

Pharmacological inhibition of DKK1 promotes spine fusion in an ovariectomized rat model

Osteoporosis is common in patients undergoing spine surgery, and carries a considerable risk of adverse outcomes. New methods to positively influence bone regeneration and spine fusion under osteoporotic conditions would be impactful. Neutralizing anti-Dickkopf-1 (DKK1) antibodies has been used as a bone anabolic agent, and recently reported by our group to aid in stem cell-mediated appendicular bone regeneration. Here, a small molecule designed as a DKK1 inhibitor, WAY-262611, was used to induce posterolateral spine fusion in an ovariectomized rat model. In vitro, pharmacological inhibition of DKK1 enhanced osteogenesis and Wnt signaling activity among rat bone marrow-derived stem/stromal cells (BMSCs). In vivo, systemic treatment with WAY-262611 promoted both chondrogenesis and osteogenesis within the spinal fusion site, and ultimately led to significant improvements in lumbar fusion as assessed by XR, μCT, histology and manual palpation assessments. No significant effect on osteoclast numbers or fusion site angiogenesis was detected, suggesting a primary direct effect on mesenchymal cells of the implantation site. Finally, evidence from human stem/stromal cells further demonstrated that pharmacologic inhibition of DKK1 promoted osteogenic differentiation in vitro. Taken together, our results suggest that targeting DKK1 promotes local bone formation and suggests potential clinical value for osteoporotic bone repair.

Agomelatine Changed the Expression and Methylation Status of Inflammatory Genes in Blood and Brain Structures of Male Wistar Rats after Chronic Mild Stress Procedure

The preclinical research conducted so far suggest that depression development may be influenced by the inflammatory pathways both at the periphery and within the central nervous system. Furthermore, inflammation is considered to be strongly connected with antidepressant treatment resistance. Thus, this study explores whether the chronic mild stress (CMS) procedure and agomelatine treatment induce changes in TGFA, TGFB, IRF1, PTGS2 and IKBKB expression and methylation status in peripheral blood mononuclear cells (PBMCs) and in the brain structures of rats. Adult male Wistar rats were subjected to the CMS and further divided into matched subgroups to receive vehicle or agomelatine. TaqMan gene expression assay and methylation-sensitive high-resolution melting (MS-HRM) were used to evaluate the expression of the genes and the methylation status of their promoters, respectively. Our findings confirm that both CMS and antidepressant agomelatine treatment influenced the expression level and methylation status of the promoter region of investigated genes in PBMCs and the brain. What is more, the present study showed that response to either stress stimuli or agomelatine differed between brain structures. Concluding, our results indicate that TGFA, TGFB, PTGS2, IRF1 and IKBKB could be associated with depression and its treatment.

Insight into the Inclusion Complexation of Fluconazole with Sulfonatocalix[4]naphthalene in Aqueous Solution, Solid-State, and Its Antimycotic Activity

The study aims to assess the interaction between fluconazole and sulfonatocalix[4]naphthalene towards enhancing its dissolution performance and antimycotic activity. A solubility study was carried out at different pH conditions, and the results revealed the formation of a 1:1 molar ratio fluconazole-sulfonatocalix[4]naphthalene inclusion complex with an A_L type phase solubility diagrams. The solid powder systems of fluconazole-sulfonatocalix[4]naphthalene were prepared using kneaded and co-evaporation techniques and physical mixtures. DCS, PXRD, TGA-DTG, FT-IR, and in vitro dissolution performance characterize the prepared systems. According to physicochemical characterization, the co-evaporation approach produces an amorphous inclusion complex of the drug inside the cavity of sulfonatocalix[4]naphthalene. The co-evaporate product significantly increased the drug dissolution rate up to 93 ± 1.77% within 10 min, unlike other prepared solid powders. The antimycotic activity showed an increase substantially (p ≤ 0.05, t-test) antimycotic activity of fluconazole co-evaporate mixture with sulfonatocalix[4]naphthalene compared with fluconazole alone against clinical strains of Candida albicans and Candida glabrata. In conclusion, sulfonatocalix[4]naphthalene could be considered an efficient complexing agent for fluconazole to enhance its aqueous solubility, dissolution performance, and antimycotic activity.

Pharmacokinetics, pharmacodynamics, and safety of verinurad with and without allopurinol in healthy Asian, Chinese, and non-Asian participants

Verinurad is a selective inhibitor of uric acid transporter 1 (URAT1). Here, we assessed the safety, pharmacokinetics, and pharmacodynamics of verinurad + allopurinol and verinurad monotherapy in healthy participants. Studies 1 (NCT03836599) and 2 (NCT02608710) were randomized Phase 1 studies. In Study 1, 12 healthy Asian participants received 24 mg verinurad + 300 mg allopurinol or placebo, and 9 healthy Chinese participants received 12 mg verinurad + 300 mg allopurinol. In Study 2, 24 healthy non-Asian male participants received 12 mg verinurad. Safety analyses included assessment of adverse events (AEs). Pharmacokinetic parameters included maximum concentration (Cmax ) and area under plasma concentration-time curve (AUC) over 24 h (AUCτ ). Pharmacodynamic parameters included percentage change from baseline (day -1) in serum uric acid (sUA) and urinary uric acid (uUA). There were no serious AEs or deaths in either study. In Study 1, steady-state geometric mean (gCV%) Cmax and AUCτ values of verinurad after 7 days' dosing were 73.6 (29.0) ng/mL and 478 (18.4) ng·h/mL, respectively, in healthy Asian participants, and 42.0 (40.1) ng/mL and 264 (36.1) ng·h/mL, respectively, in healthy Chinese participants; in Study 2, gCV% values were 36.3 (36.5) ng/mL and 271 (31.0) ng·h/mL, respectively. sUA decreased and uUA excretion increased compared with baseline following verinurad + allopurinol (Study 1) or verinurad (Study 2). When accounting for dose, the steady-state pharmacokinetics of verinurad following multiple dosing were comparable between healthy Asian and Chinese participants and healthy non-Asian participants. Verinurad treatments were well tolerated, including at higher verinurad exposures than previously evaluated after repeated dosing.

Design, synthesis, and insecticidal activities of propargyloxy-naphthalene-sulfonamide derivatives

In our previous studies, a kind of novel benzenesulfonamides was found to be a candidate insecticidal compounds. It was shown that propargyloxy and sulfonamide groups are pharmacodynamic groups. One hundred and twenty-six (126) naphthalenesulfonamides derivatives with propargyloxy functionality were designed and synthesized, and their insecticidal activities were determined. Some of them showed outstanding activity, with LC₅₀ values as low as 0.202 mg ml^-1, much lower than that of the positive control celangulin V (23.9 mg ml^-1). In addition, the structure-activity relationships were discussed, and molecular docking was used to verify the binding mode of the compound and the target receptor.

Combining explainable machine learning, demographic and multi-omic data to inform precision medicine strategies for inflammatory bowel disease

Inflammatory bowel diseases (IBDs), including ulcerative colitis and Crohn’s disease, affect several million individuals worldwide. These diseases are heterogeneous at the clinical, immunological and genetic levels and result from complex host and environmental interactions. Investigating drug efficacy for IBD can improve our understanding of why treatment response can vary between patients. We propose an explainable machine learning (ML) approach that combines bioinformatics and domain insight, to integrate multi-modal data and predict inter-patient variation in drug response. Using explanation of our models, we interpret the ML models’ predictions to infer unique combinations of important features associated with pharmacological responses obtained during preclinical testing of drug candidates in ex vivo patient-derived fresh tissues. Our inferred multi-modal features that are predictive of drug efficacy include multi-omic data (genomic and transcriptomic), demographic, medicinal and pharmacological data. Our aim is to understand variation in patient responses before a drug candidate moves forward to clinical trials. As a pharmacological measure of drug efficacy, we measured the reduction in the release of the inflammatory cytokine TNFα from the fresh IBD tissues in the presence/absence of test drugs. We initially explored the effects of a mitogen-activated protein kinase (MAPK) inhibitor; however, we later showed our approach can be applied to other targets, test drugs or mechanisms of interest. Our best model predicted TNFα levels from demographic, medicinal and genomic features with an error of only 4.98% on unseen patients. We incorporated transcriptomic data to validate insights from genomic features. Our results showed variations in drug effectiveness (measured by ex vivo assays) between patients that differed in gender, age or condition and linked new genetic polymorphisms to patient response variation to the anti-inflammatory treatment BIRB796 (Doramapimod). Our approach models IBD drug response while also identifying its most predictive features as part of a transparent ML precision medicine strategy.

[Naphthalene allyl trifluoromethyl benzocyclopentanone inhibits proliferation and induces apoptosis of lung cancer A549 cells in vitro]

OBJECTIVE

To investigate the molecular mechanism by which a novel naphthalene allyl trifluoromethyl benzocyclopentanone XX0335 inhibits the proliferation and induces apoptosis of lung cancer A549 cells.

METHODS

Lung cancer A549 cells were treated with 0.1% DMSO (control) or different concentrations (6.25, 12.5, and 25 μg/mL) of XX0335, and the changes in cell viability, cell cycle, proliferation and apoptosis were assessed with CCK-8 assay, EdU experiment, and flow cytometry. The effects of different concentrations of XX0335 on phosphorylation levels of proliferation-related proteins Akt, mTOR, Akt/mTOR and the expressions of cleaved PARP and cyclin D1 were determined using Western blotting. We also assessed the effect of XX0335 on tumor growth in a mouse model bearing A945 cell xenograft.

RESULTS

Treatment with XX0335 reduced the viability of A549 cells in a dose-dependent manner (P < 0.01) and significantly inhibited cell proliferation (P < 0.001). Flow cytometry showed that XX0335 treatment promoted apoptosis of the cells (P < 0.01) and caused an obvious increase of the number of G1-phase cells. Compared with DMSO, XX0335 significantly inhibited the phosphorylation of Akt and mTOR, increased the expression of cleaved PARP, and lowered the protein expression of cyclin D1. In the tumor-bearing mouse models, injection of XX0335 significantly decreased the tumor volume (P < 0.01).

CONCLUSION

XX0335 inhibits the proliferation, cycle and induces apoptosis of lung cancer A549 cells possibly by inhibiting the Akt/mTOR signal pathway.

NIR-Responsive Lysosomotropic Phototrigger: An "AIE + ESIPT" Active Naphthalene-Based Single-Component Photoresponsive Nanocarrier with Two-Photon Uncaging and Real-Time Monitoring Ability

In recent times, organelle-targeted drug delivery systems have gained tremendous attention due to the site-specific delivery of active drug molecules, resulting in enhanced bioefficacy. In this context, a phototriggered drug delivery system (DDS) for releasing an active molecule is superior, as it provides spatial and temporal control over the release. So far, a near-infrared (NIR) light-responsive organelle-targeted DDS has not yet been developed. Hence, we introduced a two-photon NIR light-responsive lysosome-targeted "AIE + ESIPT" active single-component DDS based on the naphthalene chromophore. The two-photon absorption cross section of our DDS is 142 GM at 850 nm. The DDS was converted into pure organic nanoparticles for biological applications. Our nano-DDS is capable of selective targeting, AIE luminogenic imaging, and drug release within the lysosome. In vitro studies using cancerous cell lines showed that our single-component photoresponsive nanocarrier exhibited enhanced cytotoxicity and real-time monitoring ability of drug release.

Ligiamycins A and B, Decalin-Amino-Maleimides from the Co-Culture of Streptomyces sp. and Achromobacter sp. Isolated from the Marine Wharf Roach, Ligia exotica

Streptomyces sp. GET02.ST and Achromobacter sp. GET02.AC were isolated together from the gut of the wharf roach, Ligia exotica, inhabiting the intertidal zone of the west coast of Korea. The co-cultivation of these two strains significantly induced the production of two new metabolites, ligiamycins A (1) and B (2), which were barely detected in the single culture of Streptomyces sp. GET02.ST. The planar structures of ligiamycins A (1) and B (2) were elucidated as new decalins coupled with amino-maleimides by the analysis of various spectroscopic data, including nuclear magnetic resonance (NMR), ultraviolet (UV), and mass (MS) data. The assignment of two nitrogen atoms in amino-maleimide in 1 was accomplished based on 1H-15N heteroatom single quantum coherence spectroscopy (HSQC) NMR experiments. The relative configurations of the ligiamycins were determined using rotating frame Overhauser effect spectroscopy (ROESY) NMR data, and their absolute configurations were deduced by comparing their experimental and calculated optical rotations. Ligiamycin A (1) displayed antibacterial effects against Staphylococcus aureus and Salmonella enterica, while ligiamycin B (2) exhibited mild cell cytotoxicity against human colorectal cancer cells.

MF-094, a potent and selective USP30 inhibitor, accelerates diabetic wound healing by inhibiting the NLRP3 inflammasome

Diabetes is a prevalent disease worldwide that can result in several complications, including renal failure, blindness, and amputation. Diabetic foot ulcers, which have the characteristics of chronic wounds, are a devastating component of diabetes progression that can lead to lower extremity amputation. In this study, we set out to investigate the mechanisms involved in wound healing of diabetic foot ulcers. The expression of USP30 in skin tissues of patients with diabetic foot ulcers and HSF2 human skin fibroblasts treated with advanced glycation end (AGE) products was detected by qRT-PCR, and CCK-8, cell scratch and ELISA assay were used to detect cell viability, migration and levels of Col I, Col III, MMP-2, MMP-9, IL-1β and IL-18. The interaction between USP30 and NLRP3 was verified by co-immunoprecipitation and ubiquitination assays. The expression of USP30, NLRP3 and caspase-1 p20 was detected by Western blot. USP30 inhibitor MF-094 was used to treat diabetic rat model established by streptozotocin (STZ). We found that USP30, a deubiquitinase, was upregulated in skin tissues of patients with diabetic foot ulcers compared with normal skin tissues. In vitro, we found that treatment of HSF2 human skin fibroblasts with advanced glycation end (AGE) products, known to contribute to diabetic complications, resulted in suppressed viability and migration of HSF2 cells, as well as increased levels of USP30 mRNA and protein. Functionally, downregulation of USP30 via shRNA-mediated knockdown or treatment with the USP30 inhibitor MF-094, restored viability and migration of AGE-treated HSF2 cells. We identified the NLRP3 inflammasome as a critical target of USP30 in AGE-induced functions. Mechanistically, we demonstrate that USP30 activates the NLRP3 inflammasome by deubiquitinating NLRP3. Finally, we show that inhibition of USP30 via MF-094 treatment facilitated wound healing in diabetic rats and resulted in decreased protein levels of NLRP3 and its downstream target caspase-1 p20, thus establishing the physiological importance of the identified USP30-NLRP3 link. Together, our findings suggest a therapeutic potential for USP30 in diabetic foot ulcers.

Design and Evaluation of a Novel Peptide-Drug Conjugate Covalently Targeting SARS-CoV-2 Papain-like Protease

Coronavirus disease 2019 (COVID-19) pandemic, a global health threat, was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 papain-like cysteine protease (PLpro) was recognized as a promising drug target because of multiple functions in virus maturation and antiviral immune responses. Inhibitor GRL0617 occupied the interferon-stimulated gene 15 (ISG15) C-terminus-binding pocket and showed an effective antiviral inhibition. Here, we described a novel peptide-drug conjugate (PDC), in which GRL0617 was linked to a sulfonium-tethered peptide derived from PLpro-specific substrate LRGG. The EM-C and EC-M PDCs showed a promising in vitro IC50 of 7.40 ± 0.37 and 8.63 ± 0.55 μM, respectively. EC-M could covalently label PLpro active site C111 and display anti-ISGylation activities in cellular assays. The results represent the first attempt to design PDCs composed of stabilized peptide inhibitors and GRL0617 to inhibit PLpro. These novel PDCs provide promising opportunities for antiviral drug design.

Role of primary sensory neurone cannabinoid type-1 receptors in pain and the analgesic effects of the peripherally acting agonist CB-13 in mice

BACKGROUND

Cannabinoid type-1 receptors (CB1Rs) are expressed in primary sensory neurones, but their role in pain modulation remains unclear.

METHODS

We produced Pirt-CB1R conditional knockout (cKO) mice to delete CB1Rs in primary sensory neurones selectively, and used behavioural, pharmacological, and electrophysiological approaches to examine the influence of peripheral CB1R signalling on nociceptive and inflammatory pain.

RESULTS

Conditional knockout of Pirt-CB1R did not alter mechanical or heat nociceptive thresholds, complete Freund adjuvant-induced inflammation, or heat hyperalgesia in vivo. The intrinsic membrane properties of small-diameter dorsal root ganglion neurones were also comparable between cKO and wild-type mice. Systemic administration of CB-13, a peripherally restricted CB1/CB2R dual agonist (5 mg kg-1), inhibited nociceptive pain and complete Freund adjuvant-induced inflammatory pain. These effects of CB-13 were diminished in Pirt-CB1R cKO mice. In small-diameter neurones from wild-type mice, CB-13 concentration-dependently inhibited high-voltage activated calcium current (HVA-ICa) and induced a rightward shift of the channel open probability curve. The effects of CB-13 were significantly attenuated by AM6545 (a CB1R antagonist) and Pirt-CB1R cKO.

CONCLUSION

CB1R signalling in primary sensory neurones did not inhibit nociceptive or inflammatory pain, or the intrinsic excitability of nociceptive neurones. However, peripheral CB1Rs are important for the analgesic effects of systemically administered CB-13. In addition, HVA-ICa inhibition appears to be a key ionic mechanism for CB-13-induced pain inhibition. Thus, peripherally restricted CB1R agonists could have utility for pain treatment.

Albicanol inhibits the toxicity of profenofos to grass carp hepatocytes cells through the ROS/PTEN/PI3K/AKT axis

Profenofos (PFF) as an environmental pollutant seriously harms the health of aquatic animals, and even endangers human safety through the food chain. Albicanol, a sesquiterpenoid extraction from the Dryopteris fragrans, has previously been shown to effectively exhibit anti-aging, anti-oxidant, and antagonize the toxicity of heavy metals. However, the mechanism of hepatocyte toxicity caused by PFF and the role that Albicanol plays in this process are still unclear. In this study, a PFF poisoning model was established by treating grass carp hepatocytes cells with PFF (150 μM) for 24 h The results of AO/EB staining, Tunel staining and flow cytometry showed that the proportion of apoptotic liver cells increased significantly after exposure. The results of ROS staining show that compared with the control group, ROS levels and PTEN/PI3K/AKT-related gene expression were up-regulated after PFF exposure. RT-qPCR and Western blotting results showed that the expression of PTEN/PI3K/AKT related genes was up-regulated. These results indicate that PFF can induce oxidative stress in hepatocytes and inhibit the phosphorylation of AKT. We further found that the expressions of Bax, CytC, Caspase-3, Caspase-9, Caspase-8 and TNFR1 after PFF exposure were significantly higher than those of the control group, and Bcl-2/Bax was significantly lower than that of the control group. These results indicate that PFF can induce oxidative stress in hepatocytes and inhibit the phosphorylation of AKT and activate mitochondrial apoptosis. Using Albicanol (5 × 10^-5 μg mL^-1) can significantly reduce the above-mentioned effects of PFF exposure on grass carp hepatocytes cells. In summary, Albicanol inhibits PFF-induced apoptosis by regulating the ROS/PTEN/PI3K/AKT pathway.