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1.
Sci Rep ; 14(1): 8401, 2024 04 10.
Article En | MEDLINE | ID: mdl-38600172

REV-ERBα, a therapeutically promising nuclear hormone receptor, plays a crucial role in regulating various physiological processes such as the circadian clock, inflammation, and metabolism. However, the availability of chemical probes to investigate the pharmacology of this receptor is limited, with SR8278 being the only identified synthetic antagonist. Moreover, no X-ray crystal structures are currently available that demonstrate the binding of REV-ERBα to antagonist ligands. This lack of structural information impedes the development of targeted therapeutics. To address this issue, we employed Gaussian accelerated molecular dynamics (GaMD) simulations to investigate the binding pathway of SR8278 to REV-ERBα. For comparison, we also used GaMD to observe the ligand binding process of STL1267, for which an X-ray structure is available. GaMD simulations successfully captured the binding of both ligands to the receptor's orthosteric site and predicted the ligand binding pathway and important amino acid residues involved in the antagonist SR8278 binding. This study highlights the effectiveness of GaMD in investigating protein-ligand interactions, particularly in the context of drug recognition for nuclear hormone receptors.


Isoquinolines , Nuclear Receptor Subfamily 1, Group D, Member 1 , Ligands , Nuclear Receptor Subfamily 1, Group D, Member 1/metabolism , Isoquinolines/chemistry , Thiophenes/chemistry , Circadian Rhythm/physiology
2.
Biochem Pharmacol ; 223: 116194, 2024 May.
Article En | MEDLINE | ID: mdl-38583812

Glutathione peroxidase 4 (GPX4) is a promising anticancer therapeutic target; however, the application of GPX4 inhibitors (GPX4i) is limited owing to intrinsic or acquired drug resistance. Hence, understanding the mechanisms underlying drug resistance and discovering molecules that can overcome drug resistance are crucial. Herein, we demonstrated that GPX4i killed bladder cancer cells by inducing lipid reactive oxygen species-mediated ferroptosis and apoptosis, and cisplatin-resistant bladder cancer cells were also resistant to GPX4i, representing a higher half-maximal inhibitory concentration value than that of parent bladder cancer cells. In addition, thioredoxin reductase 1 (TrxR1) overexpression was responsible for GPX4i resistance in cisplatin-resistant bladder cancer cells, and inhibiting TrxR1 restored the sensitivity of these cells to GPX4i. In vitro and in vivo studies revealed that Jolkinolide B (JB), a natural diterpenoid and previously identified as a TrxR1 inhibitor, potentiated the antiproliferative efficacy of GPX4i (RSL3 and ML162) against cisplatin-resistant bladder cancer cells. Furthermore, GPX4 knockdown and inhibition could augment JB-induced paraptosis and apoptosis. Our results suggest that inhibiting TrxR1 can effectively improve GPX4 inhibition-based anticancer therapy. A combination of JB and GPX4i, which is well-tolerated and has several anticancer mechanisms, may serve as a promising therapy for treating bladder cancer.


Aniline Compounds , Diterpenes , Thiophenes , Urinary Bladder Neoplasms , Humans , Cisplatin/pharmacology , Thioredoxin Reductase 1 , Cell Line, Tumor , Urinary Bladder Neoplasms/drug therapy
3.
Eur J Med Chem ; 270: 116387, 2024 Apr 15.
Article En | MEDLINE | ID: mdl-38593589

Activating apoptosis has long been viewed as an anti-cancer process, but recently increasing evidence has accumulated that induction of ferroptosis has emerged as a promising strategy for cancer therapeutics. Glutathione peroxidase 4 (GPX4) is one of the pivotal factors regulating ferroptosis that targeted inhibition or degradation of GPX4 could effectively trigger ferroptosis. In this study, a series of ML162-quinone conjugates were constructed by using pharmacophore hybridization and bioisosterism strategies, with the aim of obtaining more active anticancer agents via the ferroptosis and apoptosis dual cell death processes. Of these compounds, GIC-20 was identified as the most active one that exhibited promising anticancer activity both in vitro and in vivo via ferroptosis and apoptosis dual-targeting processes, without obvious toxicity compared with ML162. On one hand, GIC-20 could trigger ferroptosis in cells by inducing intracellular lipid peroxide and ROS accumulation, and destroying mitochondrial structure. In addition to GPX4 inhibition, GIC-20 can also trigger ferroptosis via proteasomal-mediated degradation of GPX4, suggesting GIC-20 may function as a molecule glue degrader. On the other hand, GIC-20 can also induce apoptosis via upregulating the level of apoptotic protein Bax and downregulating the level of anti-apoptotic protein Bcl-2 in HT1080 cells. Furthermore, GIC-20 also enhanced the sensitivity of resistant MIA-PaCa-2-AMG510R cells to AMG510, suggesting the great potential of GIC-20 in overcoming the acquired resistance of KRASG12C inhibitors. Overall, GIC-20 represents a novel dual ferroptosis/apoptosis inducer warranting further development for cancer therapeutics and overcoming drug resistance.


Aniline Compounds , Ferroptosis , Naphthoquinones , Neoplasms , Thiophenes , Humans , Naphthoquinones/pharmacology , Apoptosis
4.
J Vet Sci ; 25(2): e21, 2024 Mar.
Article En | MEDLINE | ID: mdl-38568823

BACKGROUND: Peste des petits ruminants (PPR) is a contagious and fatal disease of sheep and goats. PPR virus (PPRV) infection induces endoplasmic reticulum (ER) stress-mediated unfolded protein response (UPR). The activation of UPR signaling pathways and their impact on apoptosis and virus replication remains controversial. OBJECTIVES: To investigate the role of PPRV-induced ER stress and the IRE1-XBP1 and IRE1-JNK pathways and their impact on apoptosis and virus replication. METHODS: The cell viability and virus replication were assessed by 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, immunofluorescence assay, and Western blot. The expression of ER stress biomarker GRP78, IRE1, and its downstream molecules, PPRV-N protein, and apoptosis-related proteins was detected by Western blot and quantitative reverse transcription-polymerase chain reaction, respectively. 4-Phenylbutyric acid (4-PBA) and STF-083010 were respectively used to inhibit ER stress and IRE1 signaling pathway. RESULTS: The expression of GRP78, IRE1α, p-IRE1α, XBP1s, JNK, p-JNK, caspase-3, caspase-9, Bax and PPRV-N were significantly up-regulated in PPRV-infected cells, the expression of Bcl-2 was significantly down-regulated. Due to 4-PBA treatment, the expression of GRP78, p-IRE1α, XBP1s, p-JNK, caspase-3, caspase-9, Bax, and PPRV-N were significantly down-regulated, the expression of Bcl-2 was significantly up-regulated. Moreover, in PPRV-infected cells, the expression of p-IRE1α, p-JNK, Bax, and PPRV-N was significantly decreased, and the expression of Bcl-2 was increased in the presence of STF-083010. CONCLUSIONS: PPRV infection induces ER stress and IRE1 activation, resulting in apoptosis and enhancement of virus replication through IRE1-XBP1s and IRE1-JNK pathways.


Butylamines , Goat Diseases , Peste-des-Petits-Ruminants , Peste-des-petits-ruminants virus , Sheep Diseases , Sulfonamides , Thiophenes , Sheep , Animals , MAP Kinase Signaling System , Caspase 3/metabolism , Caspase 9/metabolism , Endoplasmic Reticulum Chaperone BiP , Endoribonucleases/metabolism , bcl-2-Associated X Protein/metabolism , Protein Serine-Threonine Kinases , Goats/metabolism , Apoptosis , Endoplasmic Reticulum Stress
5.
BMC Pregnancy Childbirth ; 24(1): 235, 2024 Apr 04.
Article En | MEDLINE | ID: mdl-38575932

BACKGROUND: Vaginal candidiasis (VC) commonly affects pregnant women. Traditionally, clotrimazole vaginal tablets (CLO) have been the cornerstone of management. However, sertaconazole ovules (SER) offer a novel topical antimycotic option. This double-blinded, randomized trial evaluated the efficacy of single-dose SER and CLO in treating acute VC during pregnancy. METHODS: From June 2020 to May 2021, this trial recruited pregnant women aged ≥ 18 years with VC symptoms (abnormal vaginal discharge and/or vulvar/vaginal itching) confirmed by microscopy. Participants with ≥ 4 VC episodes in the prior year, immunocompromised status, or imidazole contraindications and those who were absent at the 2-week follow-up were excluded. Participants were randomized to receive either 300 mg SER or 500 mg CLO. Evaluations 2 weeks after the initial medication administration included clinical cure (self-reported resolution of all symptoms), microscopic cure (pseudohyphal absence), patient satisfaction, side effects, and time to clinical cure. Participants with persistent VC received weekly SER doses until delivery. Assessments of recurrence and pregnancy outcomes were done. RESULTS: The analysis included 96 participants (48 per group, mean age 27.4 ± 7.4 years, gestational age at diagnosis 22.9 ± 6.4 weeks). Without statistical significance, SER achieved a higher clinical cure rate (62.5% vs 50%, p = 0.217; a mean difference of 12.5%, 95%CI: -17.5% to 42.5%; and a rate ratio of 1.25, 95%CI: 0.71 to 2.23) and a lower microscopic cure (47.9% vs. 62.5%, p = 0.151; a mean difference of -14.6%, 95%CI: -44.3% to 15.1%; and a rate ratio of 0.77, 95%CI: 0.43 to 1.37). The two groups had comparable times to clinical cure (SER: 3.1 ± 1.8 days, CLO: 3.4 ± 2.7 days; p = 0.848) and substantial satisfaction rates (SER: 66.7%, CLO: 60.4%; p = 0.753). No side effects were reported. Of 60 participants who gave birth at Siriraj Hospital, there were no significant differences in pregnancy outcomes. Repeated SER dosing eradicated symptoms and enhanced the microscopic cure rate. Recurrence was observed in four SER and two CLO participants within 1-2 months. CONCLUSION: In the treatment of acute VC during pregnancy, 300 mg SER and 500 mg CLO exhibited comparable efficacy in terms of clinical and microscopic cure rates, satisfaction, side effects, time to clinical cure, recurrence rates, and pregnancy outcomes. TRIAL REGISTRATION: TCTR20190308004 (registration date March 8, 2019).


Candidiasis, Vulvovaginal , Clotrimazole , Thiophenes , Female , Pregnancy , Humans , Young Adult , Adult , Clotrimazole/therapeutic use , Antifungal Agents/therapeutic use , Pregnant Women , Suppositories , Candidiasis, Vulvovaginal/drug therapy , Imidazoles/therapeutic use
6.
Huan Jing Ke Xue ; 45(5): 2678-2685, 2024 May 08.
Article Zh | MEDLINE | ID: mdl-38629531

Xingkai Lake, located in Heilongjiang Province, is an important fishery and agricultural base and is seriously polluted by agricultural non-point sources. To clarify the residual status of many pesticides in the surface water of Xingkai Lake, 27 types of pesticides, herbicides, and their degradation products were analyzed in rice paddy, drainage, and surface water around Xingkai Lake (China) during the rice heading and maturity periods. The results showed that all 27 types of pesticides, herbicides, and their degradation products were detected during the rice heading period, and the total concentration ranged from 247.97 to 6 094.49 ng·L-1. Additionally, 25 species were detected during the rice maturity period, and the total concentration ranged from 485.36 to 796.23 ng·L-1. In comparison, more pesticides, herbicides, and derived degradation products were detected during the heading period, and their total concentration was higher as well. During the rice heading period, atrazine, simetryn, and paclobutrazol were the main detected pesticides, atrazine and isoprothiolane were the main pesticides detected during the maturity period. The distribution characteristics of pesticides and herbicides in the surface water around Xingkai Lake (China) was similar to that in drainage, so they were probably imported from the drainage and rice paddy. The average risk quotient (RQ) values of atrazine, simetryn, prometryn, butachlor, isoprothiolane, and oxadiazon were higher than 0.1 in drainage and Xingkai Lake (China), which showed a potential risk to aquatic organisms.


Atrazine , Herbicides , Pesticide Residues , Pesticides , Thiophenes , Water Pollutants, Chemical , Pesticides/analysis , Pesticide Residues/analysis , Lakes , Environmental Monitoring , Water/chemistry , China , Risk Assessment , Water Pollutants, Chemical/analysis
7.
J Med Chem ; 67(8): 6425-6455, 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38613499

The RAS-RAF-MEK-ERK signaling cascade is abnormally activated in various tumors, playing a crucial role in mediating tumor progression. As the key component at the terminal stage of this cascade, ERK1/2 emerges as a potential antitumor target and offers a promising therapeutic strategy for tumors harboring BRAF or RAS mutations. Here, we identified 36c with a (thiophen-3-yl)aminopyrimidine scaffold as a potent ERK1/2 inhibitor through structure-guided optimization for hit 18. In preclinical studies, 36c showed powerful ERK1/2 inhibitory activities (ERK1/2 IC50 = 0.11/0.08 nM) and potent antitumor efficacy both in vitro and in vivo against triple-negative breast cancer and colorectal cancer models harboring BRAF and RAS mutations. 36c could directly inhibit ERK1/2, significantly block the phosphorylation expression of their downstream substrates p90RSK and c-Myc, and induce cell apoptosis and incomplete autophagy-related cell death. Taken together, this work provides a promising ERK1/2 lead compound for multiple tumor-treatment drug discovery.


Antineoplastic Agents , Protein Kinase Inhibitors , Pyrimidines , Humans , Pyrimidines/pharmacology , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/chemical synthesis , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Structure-Activity Relationship , Mice , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 1/antagonists & inhibitors , Thiophenes/pharmacology , Thiophenes/chemical synthesis , Thiophenes/chemistry , Mitogen-Activated Protein Kinase 3/metabolism , Mitogen-Activated Protein Kinase 3/antagonists & inhibitors , Cell Line, Tumor , Drug Discovery , Apoptosis/drug effects , Female , Mice, Nude , Drug Screening Assays, Antitumor , Molecular Structure , Cell Proliferation/drug effects , Xenograft Model Antitumor Assays , Mice, Inbred BALB C
8.
J Hazard Mater ; 470: 134175, 2024 May 15.
Article En | MEDLINE | ID: mdl-38574662

Emerging organic photoelectrochemical transistors (OPECTs) with inherent amplification capabilities, good biocompatibility and even self-powered operation have emerged as a promising detection tool, however, they are still not widely studied for pollutant detection. In this paper, a novel OPECT dual-mode aptasensor was constructed for the ultrasensitive detection of di(2-ethylhexyl) phthalate (DEHP). MXene/In2S3/In2O3 Z-scheme heterojunction was used as a light fuel for ion modulation in sensitive gated OPECT biosensing. A transistor system based on poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) converted biological events associated with photosensitive gate achieving nearly a thousand-fold higher current gain at zero bias voltage. This work quantified the target DEHP by aptamer-specific induction of CRISPR-Cas13a trans-cutting activity with target-dependent rolling circle amplification as the signal amplification unit, and incorporated the signal changes strategy of biocatalytic precipitation and TMB color development. Combining OPECT with the auxiliary validation of colorimetry (CM), high sensitivity and accurate detection of DEHP were achieved with a linear range of 0.1 pM to 200 pM and a minimum detection limit of 0.02 pM. This study not only provides a new method for the detection of DEHP, but also offers a promising prospect for the gating and application of the unique OPECT.


Aptamers, Nucleotide , Biosensing Techniques , CRISPR-Cas Systems , Diethylhexyl Phthalate , Electrochemical Techniques , Thiophenes , Transistors, Electronic , Aptamers, Nucleotide/chemistry , Diethylhexyl Phthalate/chemistry , Diethylhexyl Phthalate/analysis , Biosensing Techniques/methods , Electrochemical Techniques/instrumentation , Electrochemical Techniques/methods , Water Pollutants, Chemical/analysis , Polystyrenes/chemistry , Limit of Detection , Nucleic Acid Amplification Techniques
9.
J Mater Chem B ; 12(16): 4029-4038, 2024 Apr 24.
Article En | MEDLINE | ID: mdl-38586978

Spatiotemporal controlled drug delivery minimizes side-effects and enables therapies that require specific dosing patterns. Conjugated polymers (CP) can be used for electrically controlled drug delivery; however so far, most demonstrations were limited to molecules up to 500 Da. Larger molecules could be incorporated only during the CP polymerization and thus limited to a single delivery. This work harnesses the record volume changes of a glycolated polythiophene p(g3T2) for controlled drug delivery. p(g3T2) undergoes reversible volumetric changes of up to 300% during electrochemical doping, forming pores in the nm-size range, resulting in a conducting hydrogel. p(g3T2)-coated 3D carbon sponges enable controlled loading and release of molecules spanning molecular weights of 800-6000 Da, from simple dyes up to the hormone insulin. Molecules are loaded as a combination of electrostatic interactions with the charged polymer backbone and physical entrapment in the porous matrix. Smaller molecules leak out of the polymer while larger ones could not be loaded effectively. Finally, this work shows the temporally patterned release of molecules with molecular weight of 1300 Da and multiple reloading and release cycles without affecting the on/off ratio.


Drug Delivery Systems , Hydrogels , Polymers , Hydrogels/chemistry , Polymers/chemistry , Insulin/administration & dosage , Insulin/chemistry , Particle Size , Thiophenes/chemistry , Porosity , Drug Carriers/chemistry , Drug Liberation , Surface Properties
10.
J Med Chem ; 67(8): 6519-6536, 2024 Apr 25.
Article En | MEDLINE | ID: mdl-38592023

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has made it clear that further development of antiviral therapies will be needed. Here, we describe small-molecule inhibitors for SARS-CoV-2 Mac1, which counters ADP-ribosylation-mediated innate immune responses. Three high-throughput screening hits had the same 2-amide-3-methylester thiophene scaffold. We studied the compound binding mode using X-ray crystallography, allowing us to design analogues. Compound 27 (MDOLL-0229) had an IC50 of 2.1 µM and was selective for CoV Mac1 proteins after profiling for activity against a panel of viral and human proteins. The improved potency allowed testing of its effect on virus replication, and indeed, 27 inhibited replication of both murine hepatitis virus (MHV) prototypes CoV and SARS-CoV-2. Sequencing of a drug-resistant MHV identified mutations in Mac1, further demonstrating the specificity of 27. Compound 27 is the first Mac1-targeted small molecule demonstrated to inhibit coronavirus replication in a cell model.


Antiviral Agents , SARS-CoV-2 , Thiophenes , Virus Replication , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/chemical synthesis , Thiophenes/pharmacology , Thiophenes/chemistry , Thiophenes/chemical synthesis , Virus Replication/drug effects , Humans , SARS-CoV-2/drug effects , Animals , Drug Discovery , Mice , Crystallography, X-Ray , COVID-19 Drug Treatment , Structure-Activity Relationship , Murine hepatitis virus/drug effects
11.
Int J Mol Sci ; 25(7)2024 Apr 06.
Article En | MEDLINE | ID: mdl-38612883

Osteoporosis stands out as a prevalent skeletal ailment, prompting exploration into potential treatments, including dietary strontium ion supplements. This study assessed the efficacy of supplementation of three strontium forms-strontium citrate (SrC), strontium ranelate (SrR), and strontium chloride (SrCl)-for enhancing bone structure in 50 female SWISS mice, aged seven weeks. In total, 40 mice underwent ovariectomy, while 10 underwent sham ovariectomy. Ovariectomized (OVX) mice were randomly assigned to the following groups: OVX (no supplementation), OVX + SrR, OVX + SrC, and OVX + SrCl, at concentrations equivalent to the molar amount of strontium. After 16 weeks, micro-CT examined trabeculae and cortical bones, and whole-bone strontium content was determined. Results confirm strontium administration increased bone tissue mineral density (TMD) and Sr content, with SrC exhibiting the weakest effect. Femur morphometry showed limited Sr impact, especially in the OVX + SrC group. This research highlights strontium's potential in bone health, emphasizing variations in efficacy among its forms.


Citric Acid , Osteoporosis , Strontium , Thiophenes , Female , Animals , Mice , Bone Density , Chlorides , Citrates , Osteoporosis/drug therapy , Halogens , Disease Models, Animal
12.
Eur Endod J ; 9(2): 154-160, 2024 Mar.
Article En | MEDLINE | ID: mdl-38456465

OBJECTIVE: Triple antibiotic paste (TAP) is known to have an essential role in the success of endodontic treatment by eliminating pathogens from the root canal system. Unfortunately, it causes discolouration and cytotoxicity at high concentrations. The objective of this research was to assess and compare the antimicrobial effectiveness of various concentrations (1 mg, 5 mg, 10 mg) of TAP, TAP hydrogel (TAPH), M-TAP, and M-TAP hydrogel (MTAPH) against Enterococcus faecalis. METHODS: The agar well diffusion method was used to assess the antibiotic sensitivity of the following intracanal medicaments: TAP (ciprofloxacin, metronidazole, and minocycline) mixed in a ratio of 1: 1: 1; TAPH, M-TAP (ciprofloxacin, metronidazole, and amoxicillin), M-TAPH and plain hydrogel. Each tested medicament was individually evaluated for its antimicrobial activity against Enterococcus faecalis. Structural and topographical characterisation were analysed using a Scanning Electron Microscope (SEM) and interpreted using ImageJ software. A microdilution broth test was performed to examine the minimum inhibitory concentration and minimum bactericidal concentration (MBC) of M-TAP and TAP. RESULTS: Except for the plain hydrogel, M-TAP and hydrogel and TAP and hydrogel showed significantly varied inhibitory zones at different concentrations. M-TAPH showed the highest mean zone of inhibition of 21.6, 33.33 and 38.0 mm at a concentration of 1, 5, and 10 mg/mL when compared to TAPH, which showed a mean zone of inhibition of 3.3 mm,12.3 mm, 21.3 mm at the respective concentrations. The MIC study shows that more than 75% of Enterococcus faecalis growth was inhibited by M-TAP at a concentration of 5 µg/mL, whereas TAP showed inhibition at a concentration of 35 µg/mL. MBC results indicate that almost 99.9% of the bacterial population was killed at a concentration of 100 µg/mL (10-1) for TAP and 10 µg/mL (10-2) for M-TAP. CONCLUSION: The antibacterial efficacy of M-TAP was significantly higher than TAP. Application of M-TAP at lower doses is advised to overcome the disadvantages seen with TAP.


Anti-Infective Agents , Hydrazones , Metronidazole , Thiophenes , Metronidazole/pharmacology , Enterococcus faecalis , Hydrogels/pharmacology , Anti-Bacterial Agents/pharmacology , Ciprofloxacin , Bacitracin , Polymyxin B , Framycetin
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124198, 2024 Jun 05.
Article En | MEDLINE | ID: mdl-38552540

Polarity is a significant intracellular environmental parameter associated with cancer, while cyanide (CN-) is known to be highly toxic to humans. In this work, we designed a dual-functional fluorescent probe (TPABT) for simultaneous detection of polarity and CN-. As a polarity sensor, the probe exhibits NIR emission at 766 nm in 1,4-dioxane (non-polar solvent), whose emission intensity is 71-fold stronger than that in water (polar solvent). Meanwhile, the fluorescence intensity and quantum yield are linearly related to solvent polarity, confirming the polarity response ability of TPABT. For cell polarity detection, low cytotoxicity and polarity sensitivity of probe enable the applications for differentiating cancer cells (HeLa, 4TI) from normal cells (HUV, 3 T3) and monitoring the polarity changes of 4TI cells. As a CN- sensor, TPABT displays a turn-on fluorescence at 640 nm upon the addition of CN-, with advantages of anti-interference, response in aqueous media and low detection limit (22 nM). Additionally, we further explored the practical applications of TPABT for CN- determination in three types of real water samples (drinking water, tap water and lake water) and living cells. Notably, TPABT responses to polarity and CN- in two independent fluorescence channels of 766 and 640 nm, respectively, ensuring the dual functions for polarity and CN- sensing. Consequently, this multi-responsive fluorescent probe TPABT is promising to diagnose polarity-related diseases and detect CN- in real environments.


Drinking Water , Fluorescent Dyes , Thiophenes , Humans , Cyanides/toxicity , Spectrometry, Fluorescence , Solvents
14.
Phys Chem Chem Phys ; 26(14): 10698-10710, 2024 Apr 03.
Article En | MEDLINE | ID: mdl-38512140

Biased ligands selectively activating specific downstream signaling pathways (termed as biased activation) exhibit significant therapeutic potential. However, the conformational characteristics revealed are very limited for the biased activation, which is not conducive to biased drug development. Motivated by the issue, we combine extensive accelerated molecular dynamics simulations and an interpretable deep learning model to probe the biased activation features for two complex systems constructed by the inactive µOR and two different biased agonists (G-protein-biased agonist TRV130 and ß-arrestin-biased agonist endomorphin2). The results indicate that TRV130 binds deeper into the receptor core compared to endomorphin2, located between W2936.48 and D1142.50, and forms hydrogen bonding with D1142.50, while endomorphin2 binds above W2936.48. The G protein-biased agonist induces greater outward movements of the TM6 intracellular end, forming a typical active conformation, while the ß-arrestin-biased agonist leads to a smaller extent of outward movements of TM6. Compared with TRV130, endomorphin2 causes more pronounced inward movements of the TM7 intracellular end and more complex conformational changes of H8 and ICL1. In addition, important residues determining the two different biased activation states were further identified by using an interpretable deep learning classification model, including some common biased activation residues across Class A GPCRs like some key residues on the TM2 extracellular end, ECL2, TM5 intracellular end, TM6 intracellular end, and TM7 intracellular end, and some specific important residues of ICL3 for µOR. The observations will provide valuable information for understanding the biased activation mechanism for GPCRs.


Molecular Dynamics Simulation , Spiro Compounds , Thiophenes , GTP-Binding Proteins/metabolism , beta-Arrestins/metabolism , Machine Learning , Ligands
15.
ACS Chem Neurosci ; 15(7): 1581-1595, 2024 Apr 03.
Article En | MEDLINE | ID: mdl-38523263

Aggregated species of amyloid-ß (Aß) are one of the pathological hallmarks in Alzheimer's disease (AD), and ligands that selectively target different Aß deposits are of great interest. In this study, fluorescent thiophene-based ligands have been used to illustrate the features of different types of Aß deposits found in AD brain tissue. A dual-staining protocol based on two ligands, HS-276 and LL-1, with different photophysical and binding properties, was developed and applied on brain tissue sections from patients affected by sporadic AD or familial AD associated with the PSEN1 A431E mutation. When binding to Aß deposits, the ligands could easily be distinguished for their different fluorescence, and distinct staining patterns were revealed for these two types of AD. In sporadic AD, HS-276 consistently labeled all immunopositive Aß plaques, whereas LL-1 mainly stained cored and neuritic Aß deposits. In the PSEN1 A431E cases, each ligand was binding to specific types of Aß plaques. The ligand-labeled Aß deposits were localized in distinct cortical layers, and a laminar staining pattern could be seen. Biochemical characterization of the Aß aggregates in the individual layers also showed that the variation of ligand binding properties was associated with certain Aß peptide signatures. For the PSEN1 A431E cases, it was concluded that LL-1 was binding to cotton wool plaques, whereas HS-276 mainly stained diffuse Aß deposits. Overall, our findings showed that a combination of ligands was essential to identify distinct aggregated Aß species associated with different forms of AD.


Alzheimer Disease , Humans , Alzheimer Disease/metabolism , Thiophenes/chemistry , Ligands , Amyloid beta-Peptides/metabolism , Brain/metabolism , Plaque, Amyloid/metabolism
16.
Eur J Med Chem ; 269: 116340, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38527380

Ten new thiophene derivatives related to goniofufurone have been obtained by multistep synthesis starting from d-glucose. The critical step of the synthesis was the Grignard reaction of 2-thienyl magnesium bromide with a protected dialdose, yielding the C-5 epimeric thiophene derivatives 9 and 10. The mixture was oxidized to the 5-keto derivative 11, which after deprotection was converted to the corresponding keto-lactone 14. Stereoselective reduction of 14 afforded the thiophene mimic of goniofufurone 3. Esterification of 3 with cinnamic or 4-fluorocinnamic acid gave hybrids 5-7. Synthesized analogues were evaluated for their in vitro cytotoxicity against several tumour cell lines. The vast majority of them showed better activity than lead 1. In the culture of K562 cells, compound 3 was more active than the commercial antitumour drug doxorubicin. Structural features of analogues important for their antiproliferative activities were identified by SAR analysis. Pro-apoptotic potential examination of compound 3 on the K562 cell line was performed using flow cytometry, double fluorescence staining and apoptotic morphology screening. Results show that this derivative induces cell membrane disruptions attributable to apoptosis and induces the apoptotic morphology, but decreasing simultaneously the population of cells in the subG1 phase of the cell cycle. The results further suggest that analogue 3 achieves strong cytotoxicity without causing DNA fragmentation. This is clearly indicated by the relatively low incidence of micronuclei, as well as the SAR analysis of all biological effects.


Antineoplastic Agents , Thiophenes , Humans , Structure-Activity Relationship , Thiophenes/pharmacology , Cell Proliferation , Antineoplastic Agents/chemistry , Cell Line, Tumor , Lactones/chemistry , Drug Screening Assays, Antitumor , Molecular Structure , Apoptosis
17.
Eur J Med Chem ; 269: 116325, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38527378

By virtue of the drug repurposing strategy, the anti-osteoporosis drug raloxifene was identified as a novel PPARγ ligand through structure-based virtual high throughput screening (SB-VHTS) of FDA-approved drugs and TR-FRET competitive binding assay. Subsequent structural refinement of raloxifene led to the synthesis of a benzothiophene derivative, YGL-12. This compound exhibited potent PPARγ modulation with partial agonism, uniquely promoting adiponectin expression and inhibiting PPARγ Ser273 phosphorylation by CDK5 without inducing the expression of adipongenesis associated genes, including PPARγ, aP2, CD36, FASN and C/EBPα. This specific activity profile resulted in effective hypoglycemic properties, avoiding major TZD-related adverse effects like weight gain and hepatomegaly, which were demonstrated in db/db mice. Molecular docking studies showed that YGL-12 established additional hydrogen bonds with Ile281 and enhanced hydrogen-bond interaction with Ser289 as well as PPARγ Ser273 phosphorylation-related residues Ser342 and Glu343. These findings suggested YGL-12 as a promising T2DM therapeutic candidate, thereby providing a molecular framework for the development of novel PPARγ modulators with an enhanced therapeutic index.


PPAR gamma , Raloxifene Hydrochloride , Thiophenes , Mice , Animals , PPAR gamma/metabolism , Molecular Docking Simulation , Drug Repositioning
18.
Int J Mol Sci ; 25(6)2024 Mar 19.
Article En | MEDLINE | ID: mdl-38542429

Recent advances in melanoma therapy have significantly improved the prognosis of metastasized melanoma. However, large therapeutic gaps remain that need to be closed by new strategies. Antiapoptotic Bcl-2 proteins critically contribute to apoptosis deficiency and therapy resistance. They can be targeted by BH3 mimetics, small molecule antagonists that mimic the Bcl-2 homology domain 3 (BH3) of proapoptotic BH3-only proteins. By applying in vitro experiments, we aimed to obtain an overview of the possible suitability of BH3 mimetics for future melanoma therapy. Thus, we investigated the effects of ABT-737 and ABT-263, which target Bcl-2, Bcl-xL and Bcl-w as well as the Bcl-2-selective ABT-199 and the Mcl-1-selective S63845, in a panel of four BRAF-mutated and BRAF-WT melanoma cell lines. None of the inhibitors showed significant effectiveness when used alone; however, combination of S63845 with each one of the three ABTs almost completely abolished melanoma cell survival and induced apoptosis in up to 50-90% of the cells. Special emphasis was placed here on the understanding of the downstream pathways involved, which may allow improved applications of these strategies. Thus, cell death induction was correlated with caspase activation, loss of mitochondrial membrane potential, phosphorylation of histone H2AX, and ROS production. Caspase dependency was demonstrated by a caspase inhibitor, which blocked all effects. Upregulation of Mcl-1, induced by S63845 itself, as reported previously, was blocked by the combinations. Indeed, Mcl-1, as well as XIAP (X-linked inhibitor of apoptosis), were strongly downregulated by combination treatments. These findings demonstrate that melanoma cells can be efficiently targeted by BH3 mimetics, but the right combinations have to be selected. The observed pronounced activation of apoptosis pathways demonstrates the decisive role of apoptosis in the loss of cell viability by BH3 mimetics.


Antineoplastic Agents , Melanoma , Pyrimidines , Thiophenes , Humans , Melanoma/metabolism , Myeloid Cell Leukemia Sequence 1 Protein/metabolism , Proto-Oncogene Proteins c-bcl-2 , bcl-X Protein/metabolism , Apoptosis , Caspases/metabolism , Cell Line, Tumor , Antineoplastic Agents/pharmacology
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124126, 2024 May 15.
Article En | MEDLINE | ID: mdl-38490122

Large amount of sulphur is released by the combustion of fossil fuels in the form of SoX which affects human health and leads to acid rain. To overcome this issue, it is essential to eliminate sulphur moieties from heterocyclic organo-sulphur compounds like Dibenzothiophene (DBT) present in the petrol. In this study Surface enhanced Raman scattering (SERS) spectroscopy is used to analyze the desulfurizing activity of Tsukamurella paurometabola bacterial strain. The most prominent SERS peaks observed at 791, 837, 944 and 1032 cm-1, associated to C-S stretching, are solely observed in dibenzothiophene and its metabolite-I (DBTS) but absent in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Moreover, the SERS peaks observed at 974 (characteristic peak of benzene ring) and 1015 cm-1 is associated to C-C ring breathing while 1642 and 1655 cm-1 assigned to CC bonds of aromatic ring. These peaks are only observed in 2-Hydroxybiphenyl (metabolite-II) and extraction sample of supernatant as a result of biodesulfurization. Notably, these peaks are absent in the Dibenzothiophene and its metabolite-I which indicate that aromatic ring is carrying sulfur in this fraction. Moreover, multivariate data analytical tools like principal component analysis (PCA) and PCA-loadings are applied to further differentiate between dibenzothiophene and its metabolites that are Dibenzothiophene sulphone (metabolite-I) and 2-Hydroxybiphenyl (metabolite-II).


Actinobacteria , Biphenyl Compounds , Spectrum Analysis, Raman , Sulfur , Thiophenes , Humans , Sulfur/chemistry , Biodegradation, Environmental
20.
Eur J Pharmacol ; 970: 176510, 2024 May 05.
Article En | MEDLINE | ID: mdl-38493917

Activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway protects against N-methyl-D-aspartic acid (NMDA)-induced excitotoxic retinal injury. AMPK activation enhances fatty acid metabolism and ketone body synthesis. Ketone bodies are transported into neurons by monocarboxylate transporters (MCTs) and exert neuroprotective effects. In this study, we examined the distribution and expression levels of MCT1 and MCT2 in the retina and analyzed the effects of pharmacological inhibition of MCTs on the protective effects of metformin and 5-aminoimidazole-4-carboxamide (AICAR), activators of AMPK, against NMDA-induced retinal injury in rats. MCT1 was expressed in the blood vessels, processes of astrocytes and Müller cells, and inner segments of photoreceptors in the rat retina, whereas MCT2 was expressed in neuronal cells in the ganglion cell layer (GCL) and in astrocyte processes. The expression levels of MCT2, but not MCT1, decreased one day after intravitreal injection of NMDA (200 nmol). Intravitreal injection of NMDA decreased the number of cells in the GCL compared to the vehicle seven days after injection. Simultaneous injection of metformin (20 nmol) or AICAR (50 nmol) with NMDA attenuated NMDA-induced cell loss in the GCL, and these protective effects were attenuated by AR-C155858 (1 pmol), an inhibitor of MCTs. AR-C155858 alone had no significant effect on the retinal structure. These results suggest that AMPK-activating compounds protect against NMDA-induced excitotoxic retinal injury via mechanisms involving MCTs in rats. NMDA-induced neurotoxicity may be associated with retinal neurodegenerative changes in glaucoma and diabetic retinopathy. Therefore, AMPK-activating compounds may be effective in managing these retinal diseases.


Metformin , Retinal Diseases , Thiophenes , Uracil/analogs & derivatives , Rats , Animals , AMP-Activated Protein Kinases/metabolism , N-Methylaspartate/toxicity , Rats, Sprague-Dawley , Retina/metabolism , Retinal Diseases/chemically induced , Retinal Diseases/prevention & control , Retinal Diseases/metabolism , Membrane Transport Proteins/metabolism , Metformin/adverse effects
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