Effects of a S-metolachlor based herbicide on two plant models: Zea mays L. and Lactuca sativa L.

Corn is the second most cultivated crop in Brazil, the number-one country in pesticide consumption. Chemical control of weeds is performed using herbicides such as S-metolachlor with pre- and post-emergence action and thus the toxicity of herbicides constitutes a matter of great concern. The present investigation aimed to examine the effects of an S-metolachlor-based herbicide on Lactuca sativa L. (lettuce) and Zea mays L. (maize) utilizing various bioassays. The test solutions were prepared from commercial products containing the active ingredient. Seeds from the plant models were exposed in petri dishes and maintained under biochemical oxygen demand (BOD) at 24°C. Distilled water was negative and aluminium positive control. Macroscopic analyses (germination and growth) were conducted for both plant species, and microscopic analysis (cell cycle and chromosomal alterations) were performed for L. sativa root tip cells. Detrimental interference of S-metolachlor-based herbicide was noted with lettuce for all parameters tested reducing plant germination by over 50% and the germination speed by over 45% and showing a significant decrease in mitotic index, from 16.25% to 9,28% even on the lowest concentration tested. In maize, there was no significant interference in plant germination; however, speed of germination was significantly hampered, reaching a 51.22% reduction for the highest concentration tested. Data demonstrated that the herbicide was toxic as evidenced by its phyto- and cytotoxicity in L. sativa L. and Z. mays L.

Discovery of N-Substituted Acetamide Derivatives as Promising P2Y14R Antagonists Using Molecular Hybridization Based on Crystallographic Overlay.

P2Y14 receptor (P2Y14R) is activated by uridine 5'-diphosphate-glucose, which is involved in many human inflammatory diseases. Based on the molecular docking analysis of currently reported P2Y14R antagonists and the crystallographic overlap study between the reported P2Y14R antagonist compounds 6 and 9, a series of N-substituted-acetamide derivatives were designed, synthesized, and identified as novel and potent P2Y14R antagonists. The most potent antagonist, compound I-17 (N-(1H-benzo[d]imidazol-6-yl)-2-(4-bromophenoxy)acetamide, IC50 = 0.6 nM) without zwitterionic character, showed strong binding ability to P2Y14R, high selectivity, moderate oral bioactivity, and improved pharmacokinetic profiles. In vitro and in vivo evaluation demonstrated that compound I-17 had satisfactory inhibitory activity on the inflammatory response of monosodium urate (MSU)-induced acute gouty arthritis. I-17 decreased inflammatory factor release and cell pyroptosis through the NOD-like receptor family pyrin domain-containing 3 (NLRP3)/gasdermin D (GSDMD) signaling pathway. Thus, compound I-17, with potent P2Y14R antagonistic activity, in vitro and in vivo efficacy, and favorable bioavailability (F = 75%), could be a promising lead compound for acute gouty arthritis.

In vitro and in silico analyses reveal the toxicity of metolachlor to grass carp hepatocytes and the antagonism of melatonin.

Due to the widespread use of metolachlor (MET), the accumulation of MET and its metabolites in the environment has brought serious health problems to aquatic organisms. At present, the toxicity of MET on the physiological metabolism of aquatic animals mainly focused on the role of enzymes. There is still a lack of research on the molecular mechanisms of MET hepatotoxicity, especially on antagonizing MET toxicity. Therefore, this study focuses on grass carp hepatocytes (L8824 cells) closely related to toxin accumulation. By establishing a MET exposed L8824 cells model, it is determined that MET exposure induces pyrolytic inflammation of L8824 cells. Subsequent mechanistic studies found that MET exposure induces pyroptosis in L8824 cells through mitochondrial dysfunction, and siCaspase-1 inhibits the MET induced ROS production, suggesting a regulation of ROS-NLRP3- Caspase-1 pyroptotic inflammation cycling center in MET induced injury to L8824 cells. Molecular docking revealed a strong binding energy between melatonin (MT) and Caspase-1. Finally, a model of L8824 cells with MT intervention in MET exposure was established. MT can antagonize the pyroptosis induced by MET exposure in L8824 cells by targeting Caspase-1, thereby restoring mitochondrial function and inhibiting the ROS-pyroptosis cycle. This study discovered targets and mechanisms of MT regulating pyroptosis in MET exposed-L8824 cells, and the results are helpful to provide new targets for the design of MET antidotes.

Anti-tumor effects of tirbanibulin in squamous cell carcinoma cells are mediated via disruption of tubulin-polymerization.

Topical tirbanibulin is a highly effective and well tolerated novel treatment option for actinic keratoses (AKs). This study aimed to characterize the mode of action of tirbanibulin in keratinocytes (NHEK) and cutaneous squamous cell carcinoma (cSCC) cell lines (A431, SCC-12) in vitro. Tirbanibulin significantly reduced proliferation in a dose-dependent manner in all investigated cell lines, inhibited migration, and induced G2/M-cell cycle arrest only in the cSCC cell lines analyzed, and induced apoptosis solely in A431, which showed the highest sensitivity to tirbanibulin. In general, we detected low basal expression of phosphorylated SRC in all cell lines analyzed, therefore, interference with SRC signaling does not appear to be the driving force regarding the observed effects of tirbanibulin. The most prominent tirbanibulin-mediated effect was on ß-tubulin-polymerization, which was especially impaired in A431. Additionally, tirbanibulin induced an increase of the proinflammatory cytokines IL-1α, bFGF and VEGF in A431. In conclusion, tirbanibulin mediated anti-tumor effects predominantly in A431, while healthy keratinocytes and more dedifferentiated SCC-12 were less influenced. These effects of tirbanibulin are most likely mediated via dysregulation of ß-tubulin-polymerization and may be supported by proinflammatory aspects.

Aryl amino acetamides prevent Plasmodium falciparum ring development via targeting the lipid-transfer protein PfSTART1.

With resistance to most antimalarials increasing, it is imperative that new drugs are developed. We previously identified an aryl acetamide compound, MMV006833 (M-833), that inhibited the ring-stage development of newly invaded merozoites. Here, we select parasites resistant to M-833 and identify mutations in the START lipid transfer protein (PF3D7_0104200, PfSTART1). Introducing PfSTART1 mutations into wildtype parasites reproduces resistance to M-833 as well as to more potent analogues. PfSTART1 binding to the analogues is validated using organic solvent-based Proteome Integral Solubility Alteration (Solvent PISA) assays. Imaging of invading merozoites shows the inhibitors prevent the development of ring-stage parasites potentially by inhibiting the expansion of the encasing parasitophorous vacuole membrane. The PfSTART1-targeting compounds also block transmission to mosquitoes and with multiple stages of the parasite's lifecycle being affected, PfSTART1 represents a drug target with a new mechanism of action.

Effects of Fe(III) on the formation and toxicity alteration of halonitromethanes, dichloroacetonitrile, and dichloroacetamide from polyethyleneimine during UV/chlorine disinfection.

Trace iron ions (Fe(III)) are commonly found in water and wastewater, where free chlorine is very likely to coexist with Fe(III) affecting the disinfectant's stability and N-DBPs' fate during UV/chlorine disinfection, and yet current understanding of these mechanisms is limited. This study investigates the effects of Fe(III) on the formation and toxicity alteration of halonitromethanes (HNMs), dichloroacetonitrile (DCAN), and dichloroacetamide (DCAcAm) from polyethyleneimine (PEI) during UV/chlorine disinfection. Results reveal that the maxima concentrations of HNMs, DCAN, and DCAcAm during UV/chlorine disinfection with additional Fe(III) were 1.39, 1.38, and 1.29 times higher than those without additional Fe(III), instead of being similar to those of Fe(III) inhibited the formation of HNMs, DCAN and DCAcAm during chlorination disinfection. Meanwhile, higher Fe(III) concentration, acidic pH, and higher chlorine dose were more favorable for forming HNMs, DCAN, and DCAcAm during UV/chlorine disinfection, which were highly dependent on the involvement of HO· and Cl·. Fe(III) in the aquatic environment partially hydrolyzed to the photoactive Fe(III)­hydroxyl complexes Fe(OH)2+ and [Fe(H2O)6]3+, which undergone UV photoactivation and coupling reactions with HOCl to achieve effective Fe(III)/Fe(II) interconversion, a process that facilitated the sustainable production of HO·. Extensive product analysis and comparison verified that the HO· production enhanced by the Fe(III)/Fe(II) internal cycle played a primary role in increasing HNMs, DCAN, and DCAcAm productions during UV/chlorine disinfection. Note that the incorporation of Fe(III) increased the cytotoxicity and genotoxicity of HNMs, DCAN, and DCAcAm formed during UV/chlorine disinfection, and yet Fe(III) did not have a significant effect on the acute toxicity of water samples before, during, and after UV/chlorine disinfection. The new findings broaden the knowledge of Fe(III) affecting HNMs, DCAN, and DCAcAm formation and toxicity alteration during UV/chlorine disinfection.

2-(Methyl(phenyl)amino)-N-(phenyloxyphenyl)acetamide structural motif representing a framework for selective SIRT2 inhibition.

The mammalian cytoplasmic protein SIRT2, a class III histone deacetylase family member, possesses NAD+-dependent lysine deacetylase/deacylase activity. Dysregulation of SIRT2 has been implicated in the pathogenesis of several diseases, including neurological and metabolic disorders and cancer; thus, SIRT2 emerges as a potential therapeutic target. Herein, we identified a series of diaryl acetamides (ST61-ST90) by the structural optimization of our hit STH2, followed by enhanced SIRT2 inhibitory potency and selectivity. Among them, ST72, ST85, and ST88 selectively inhibited SIRT2 with IC50 values of 9.97, 5.74, and 8.92 µM, respectively. Finally, the entire study was accompanied by in silico prediction of binding modes of docked compounds and the stability of SIRT2-ligand complexes. We hope our findings will provide substantial information for designing selective inhibitors of SIRT2.

Synthesis of new N-(5,6-methylenedioxybenzothiazole-2-yl)-2-[(substituted)thio/piperazine]acetamide/propanamide derivatives and evaluation of their AChE, BChE, and BACE-1 inhibitory activities.

In this study, the synthesis of N-(5,6-methylenedioxybenzothiazole-2-yl)-2-[(substituted)thio/piperazine]acetamide/propanamide derivatives (3a-3k) and to investigate their acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and ß-secretase 1 (BACE-1) inhibition activity were aimed. Mass, 1H NMR, and 13C NMR spectra were utilized to determine the structure of the synthesized compounds. Compounds 3b, 3c, 3f, and 3j showed AChE inhibitory activity which compound 3c (IC50 = 0.030 ± 0.001 µM) showed AChE inhibitory activity as high as the reference drug donepezil (IC50 = 0.0201 ± 0.0010 µM). Conversely, none of the compounds showed BChE activity. Compounds 3c and 3j showed the highest BACE-1 inhibitory activity and IC50 value was found as 0.119 ± 0.004 µM for compound 3j whereas IC50 value was 0.110 ± 0.005 µM for donepezil, which is one of the reference substance. Molecular docking studies have been carried out using the data retrieved from the server of the Protein Data Bank (PDBID: 4EY7 and 2ZJM). Using in silico approach behavior active compounds (3c and 3j) and their binding modes clarified.

Novel Acetamide-Based HO-1 Inhibitor Counteracts Glioblastoma Progression by Interfering with the Hypoxic-Angiogenic Pathway.

Glioblastoma multiforme (GBM) represents the deadliest tumor among brain cancers. It is a solid tumor characterized by uncontrolled cell proliferation generating the hypoxic niches in the cancer core. By inducing the transcription of hypoxic inducible factor (HIF), hypoxia triggers many signaling cascades responsible for cancer progression and aggressiveness, including enhanced expression of vascular endothelial growth factor (VEGF) or antioxidant enzymes, such as heme oxygenase-1 (HO-1). The present work aimed to investigate the link between HO-1 expression and the hypoxic microenvironment of GBM by culturing two human glioblastoma cell lines (U87MG and A172) in the presence of a hypoxic mimetic agent, deferoxamine (DFX). By targeting hypoxia-induced HO-1, we have tested the effect of a novel acetamide-based HO-1 inhibitor (VP18/58) on GBM progression. Results have demonstrated that hypoxic conditions induced upregulation and nuclear expression of HO-1 in a cell-dependent manner related to malignant phenotype. Moreover, our data demonstrated that the HO-1 inhibitor counteracted GBM progression by modulating the HIFα/HO-1/VEGF signaling cascade in cancer cells bearing more malignant phenotypes.

Design, synthesis, and biological evaluation of chalcone acetamide derivatives against triple negative breast cancer.

Chalcones are chemical scaffolds found in natural products, particularly in plants, and are considered for structural diversity in medicinal chemistry for drug development. Herein, we designed and synthesised novel acetamide derivatives of chalcone, characterizing them using 1H NMR, 13C NMR, HRMS, and IR spectroscopic methods. These derivatives were then screened against human cancer cells for cytotoxicity using the SRB assay. Among the tested derivatives, 7g, with a pyrrolidine group, exhibited better cell growth inhibition activity against triple-negative breast cancer (TNBC) cells. Further assays, including SRB, colony formation, and fluorescent dye-based microscopic analysis, confirmed that 7g significantly inhibited MDA-MB-231 cell proliferation. Furthermore, 7g promoted apoptosis by upregulating cellular reactive oxygen species (ROS) levels and disrupting mitochondrial membrane potential (MMP). Elevated expression of pro-apoptotic proteins (Bax and caspase-3) and a higher Bax/Bcl-2 ratio with downregulation of anti-apoptotic (Bcl-2) protein levels were observed in TNBC cells. The above results suggest that 7g can promote cellular death through apoptotic mechanisms in TNBC cells.

Microwave-Assisted Atom Transfer Radical Cyclization in the Synthesis of 3,3-Dichloro-γ- and δ-Lactams from N-Alkenyl-Tethered Trichloroacetamides Catalyzed by RuCl2(PPh3)3 and Their Cytotoxic Evaluation.

An expeditious synthesis of γ- and δ-lactams from tethered alkenyl trichloroacetamides in the presence of 5% of RuCl2(PPh3)3 is reported. In this investigation we have demonstrated that microwave activation significantly enhances reaction rates, leading to the formation of the corresponding lactams in yields ranging from good to excellent. Thus, we have been able to prepare a wide range of lactams, including indole and morphan bicyclic scaffolds, where the corresponding reactions were completely diastereoselective. This process was successfully extended to α,α-dichloroamides without affecting either their yield or their diastereoselectivity. Some of the lactams prepared in this work were evaluated for their hemolytic and cytotoxic responses. All compounds were found to be non-hemolytic at the tested concentration, indicating their safety profile in terms of blood cell integrity. Meanwhile, they exhibited interesting cytotoxicity responses that depend on both their lactam structure and cell line. Among the molecules tested, γ-lactam 2a exhibited the lowest IC50 values (100-250 µg/mL) as a function of its cell line, with promising selectivity against squamous carcinoma cells (A431) in comparison with fibroblasts (3T3 cell line).

High-dose Agomelatine Combined with Haloperidol Decanoate Improves Cognition, Downregulates MT2, Upregulates D5, and Maintains Krüppel-like Factor 9 But Alters Cardiac Electrophysiology.

Haloperidol decanoate (HD) has been implicated in cognitive impairment. Agomelatine (AGO) has been claimed to improve cognition. We aimed at investigating the effects of HD + low- or high-dose AGO on cognition, verifying the melatonergic/dopaminergic to the cholinergic hypothesis of cognition and exploring relevant cardiovascular issues in adult male Wistar albino rats. HD + high-dose AGO prolonged the step-through latency by +61.47% (P < 0.0001), increased the time spent in bright light by +439.49% (P < 0.0001), reduced the time spent in dim light by -66.25% (P < 0.0001), and increased the percent of alternations by +71.25% (P < 0.0001), despite the reductions in brain acetylcholine level by -10.67% (P < 0.0001). Neurodegeneration was minimal, while the mean power frequency of the source wave was reduced by -23.39% (P < 0.05). Concurrently, the relative expression of brain melatonin type 2 receptors was reduced by -18.75% (P < 0.05), against increased expressions of dopamine type 5 receptors by +22.22% (P < 0.0001) and angiopoietin-like 4 by +119.18% (P < 0.0001). Meanwhile, electrocardiogram (ECG) demonstrated inverted P wave, reduced P wave duration by -36.15% (P < 0.0001) and PR interval by -19.91% (P < 0.0001), prolonged RR interval by +27.97% (P < 0.05), increased R wave amplitude by +523.15% (P < 0.0001), and a depressed ST segment and inverted T wave. In rats administered AGO, HD, or HD+ low-dose AGO, Alzheimer's disease (AD)-like neuropathologic features were more evident, accompanied by extensive ECG and neurochemical alterations. HD + high-dose AGO enhances cognition but alters cardiac electrophysiology. SIGNIFICANCE STATEMENT: Given the issue of cognitive impairment associated with HD and the claimed cognitive-enhancing activity of AGO, combined high-dose AGO with HD improved cognition of adult male rats, who exhibited minimal neurodegenerative changes. HD+ high-dose AGO was relatively safe regarding triggering epileptogenesis, while it altered cardiac electrophysiology. In the presence of low acetylcholine, the melatonergic/dopaminergic hypothesis, added to angiopoietin-like 4 and Krüppel-like factor 9, could offer some clue, thus offering novel targets for pharmacologic manipulation of cognition.

Metabolism-based category formation for the prioritisation of genotoxicity hazard assessment for plant protection product residues (Part 4): α-Chloroacetamides.

In dietary risk assessment of plant protection products, residues of active ingredients and their metabolites need to be evaluated for their genotoxic potential. The European Food Safety Authority recommend a tiered approach focussing assessment and testing on classes of similar chemicals. To characterise similarity, in terms of metabolism, a metabolic similarity profiling scheme has been developed from an analysis of 69 α-chloroacetamide herbicides for which either Ames, chromosomal aberration or micronucleus test results are publicly available. A set of structural space alerts were defined, each linked to a key metabolic transformation present in the α-chloroacetamide metabolic space. The structural space alerts were combined with covalent chemistry profiling to develop categories suitable for chemical prioritisation via read-across. The method is a robust and reproducible approach to such read-across predictions, with the potential to reduce unnecessary testing. The key challenge in the approach was identified as being the need for metabolism data individual groups of plant protection products as the basis for the development of the structural space alerts.

Synthesis of novel indol-3-acetamido analogues as potent anticancer agents, biological evaluation and molecular modeling studies.

Cannabinoids bind to cannabinoid receptors CB1 and CB2 and their antitumoral activity has been reported against some various cancer cell lines. Some synthetic cannabinoids possessing indole rings such as JWH-015 and JWH-133 particularly bind to the cannabinoid CB2 receptor and it was reported that they inhibit the proliferation and growth of various cancer cells without their psychoactive effects. However, the pharmacological action mechanisms of the cannabinoids are completely unknown. In this study, we report the synthesis of some new cannabinoidic novel indoles and evaluate their anticancer activity on various cancerous and normal cell lines (U87, RPMI 8226, HL60 and L929) using several cellular and molecular assays including MTT assay, real-time q-PCR, scratch assay, DAPI assay, Annexin V-PE/7AAD staining, caspase3/7 activity tests. Our findings indicated that compounds 7, 10, 13, 16, and 17 could reduce cell viability effectively. Compound 17 markedly increased proapoptotic genes (BAX, BAD, and BIM), tumor suppressor gene (p53) expression levels as well as the BAX/BCL-2 ratio in U87 cells. In addition, 17 inhibited cell migration. Based on these results, 17 was chosen for determining the mechanism of cell death in U87 cells. DAPI and Annexin V-7AAD staining results showed that 17 induced apoptosis, moreover activated caspase 3/7 significantly. Hence, compound 17, was selected as a lead compound for further pharmacomodulation. To rationalize the observed biological activities of 17, our study also included a comprehensive analysis using molecular docking and MD simulations. This integrative approach revealed that 17 fits tightly into the active site of the CB2 receptor and is involved in key interactions that may be responsible for its anti-proliferative effects.

MPoMA protects against lung epithelial cell injury via p65 degradation.

Numerous cases of lung injury caused by viral infection were reported during the coronavirus disease-19 pandemic. While there have been significant efforts to develop drugs that block viral infection and spread, the development of drugs to reduce or reverse lung injury has been a lower priority. This study aimed to identify compounds from a library of compounds that prevent viral infection that could reduce and prevent lung epithelial cell damage. We investigated the cytotoxicity of the compounds, their activity in inhibiting viral spike protein binding to cells, and their activity in reducing IL-8 production in lung epithelial cells damaged by amodiaquine (AQ). We identified N-(4-(4-methoxyphenoxy)-3-methylphenyl)-N-methylacetamide (MPoMA) as a non-cytotoxic inhibitor against viral infection and AQ-induced cell damage. MPoMA inhibited the expression of IL-8, IL-6, IL-1ß, and fibronectin induced by AQ and protected against AQ-induced morphological changes. However, MPoMA did not affect basal IL-8 expression in lung epithelial cells in the absence of AQ. Further mechanistic analysis confirmed that MPoMA selectively promoted the proteasomal degradation of inflammatory mediator p65, thereby reducing intracellular p65 expression and p65-mediated inflammatory responses. MPoMA exerted potent anti-inflammatory and protective functions in epithelial cells against LPS-induced acute lung injury in vivo. These findings suggest that MPoMA may have beneficial effects in suppressing viral infection and preventing lung epithelial cell damage through the degradation of p65 and inhibition of the production of inflammatory cytokines.

Enantioselectivity regulation of antibody against chiral herbicide metolachlor based on interaction at chiral center.

Enantioselective antibodies have emerged as great potential biomaterials in the fields of immunoassays and chiral separation. However, cross-reactivity of antibodies to the distomer may severely restrict the application. Comprehending the interaction mechanism between antibodies and enantiomers could be beneficial to produce superior enantioselective antibodies. In this study, a pair of recombinant antibodies (RAbs) against metolachlor enantiomers at chiral carbon (αSS-MET and αSR-MET) were generated and characterized. The αSS-MET-RAb and αSR-MET-RAb showed comparable sensitivity and specificity to the parental monoclonal antibodies by icELISA, with IC50 values of 3.45 and 223.77 ng/mL, respectively. Moreover, the complex structures of RAbs and corresponding eutomer were constructed and analyzed, and site-specific mutagenesis was utilized to verify the reliability of the enantioselective mechanism elucidated. It demonstrated that the strength of the interaction between the chiral center region of eutomer and the antibody was the key factor for the enantioselectivity of antibody. Increasing this interaction could limit the conformational adjustment of the distomer in a specific chiral recognition cavity, thus decreasing the affinity of the antibody to the distomer. This work provided the in-depth analysis of enantioselective mechanism for two RAbs and paved the way to regulate antibody enantioselective performance for immunoassays of chiral compounds.

CXCL4/CXCR3 axis regulates cardiac fibrosis by activating TGF-ß1/Smad2/3 signaling in mouse viral myocarditis.

BACKGROUND: Severe myocarditis is often accompanied by cardiac fibrosis, but the underlying mechanism has not been fully elucidated. CXCL4 is a chemokine that has been reported to have pro-inflammatory and profibrotic functions. The exact role of CXCL4 in cardiac fibrosis remains unclear. METHODS: Viral myocarditis (VMC) models were induced by intraperitoneal injection of Coxsackie B Type 3 (CVB3). In vivo, CVB3 (100 TCID50) and CVB3-AMG487 (CVB3: 100 TCID50; AMG487: 5 mg/kg) combination were administered in the VMC and VMC+AMG487 groups, respectively. Hematoxylin and eosin staining, severity score, Masson staining, and immunofluorescence staining were performed to measure myocardial morphology in VMC. Enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were performed to quantify inflammatory factors (IL-1ß, IL-6, TNF-α, and CXCL4). Aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and creatine kinase-myocardial band (CK-MB) levels were analyzed by commercial kits. CXCL4, CXCR3B, α-SMA, TGF-ß1, Collagen I, and Collagen III were determined by Western blot and immunofluorescence staining. RESULTS: In vivo, CVB3-AMG487 reduced cardiac injury, α-SMA, Collagen I and Collagen III levels, and collagen deposition in VMC+AMG487 group. Additionally, compared with VMC group, VMC+AMG group decreased the levels of inflammatory factors (IL-1ß, IL-6, and TNF-α). In vitro, CXCL4/CXCR3B axis activation TGF-ß1/Smad2/3 pathway promote mice cardiac fibroblasts differentiation. CONCLUSION: CXCL4 acts as a profibrotic factor in TGF-ß1/Smad2/3 pathway-induced cardiac fibroblast activation and ECM synthesis, and eventually progresses to cardiac fibrosis. Therefore, our findings revealed the role of CXCL4 in VMC and unveiled its underlying mechanism. CXCL4 appears to be a potential target for the treatment of VMC.

Protein quality control systems in the endoplasmic reticulum and the cytosol coordinately prevent alachlor-induced proteotoxic stress in Saccharomyces cerevisiae.

Alachlor, a widely used chloroacetanilide herbicide for controlling annual grasses in crops, has been reported to rapidly trigger protein denaturation and aggregation in the eukaryotic model organism Saccharomyces cerevisiae. Therefore, this study aimed to uncover cellular mechanisms involved in preventing alachlor-induced proteotoxicity. The findings reveal that the ubiquitin-proteasome system (UPS) plays a crucial role in eliminating alachlor-denatured proteins by tagging them with polyubiquitin for subsequent proteasomal degradation. Exposure to alachlor rapidly induced an inhibition of proteasome activity by 90 % within 30 min. The molecular docking analysis suggests that this inhibition likely results from the binding of alachlor to ß subunits within the catalytic core of the proteasome. Notably, our data suggest that nascent proteins in the endoplasmic reticulum (ER) are the primary targets of alachlor. Consequently, the unfolded protein response (UPR), responsible for coping with aberrant proteins in the ER, becomes activated within 1 h of alachlor treatment, leading to the splicing of HAC1 mRNA into the active transcription activator Hac1p and the upregulation of UPR gene expression. These findings underscore the critical roles of the protein quality control systems UPS and UPR in mitigating alachlor-induced proteotoxicity by degrading alachlor-denatured proteins and enhancing the protein folding capacity of the ER.

Magnetite-driven Bio-Fenton degradation of chloroacetanilide herbicides by a newly isolated hydrogen peroxide producing bacterium Desemzia sp. strain C1.

The efficiency of the Fenton reaction is markedly contingent upon the operational pH related to iron solubility. Therefore, a heterogeneous Fenton reaction has been developed to function at neutral pH. In the present study, the Bio-Fenton reaction was carried out using magnetite (Fe(II)Fe(III)2O4) and H2O2 generated by a newly isolated H2O2-producing bacterium, Desemzia sp. strain C1 at pH 6.8 to degrade chloroacetanilide herbicides. The optimal conditions for an efficient Bio-Fenton reaction were 10 mM of lactate, 0.5% (w/v) of magnetite, and resting-cells (O.D.600 = 1) of strain C1. During the Bio-Fenton reaction, 1.8-2.0 mM of H2O2 was generated by strain C1 and promptly consumed by the Fenton reaction with magnetite, maintaining stable pH conditions. Approximately, 40-50% of the herbicides underwent oxidation through non-specific reactions of •OH, leading to dealkylation, dechlorination, and hydroxylation via hydrogen atom abstraction. These findings will contribute to advancing the Bio-Fenton system for non-specific oxidative degradation of diverse organic pollutants under in-situ environmental conditions with bacteria producing high amount of H2O2 and magnetite under a neutral pH condition.

Discovery of a novel SHP2 allosteric inhibitor using virtual screening, FMO calculation, and molecular dynamic simulation.

CONTEXT: SHP2 is a non-receptor protein tyrosine phosphatase to remove tyrosine phosphorylation. Functionally, SHP2 is an essential bridge to connect numerous oncogenic cell-signaling cascades including RAS-ERK, PI3K-AKT, JAK-STAT, and PD-1/PD-L1 pathways. This study aims to discover novel and potent SHP2 inhibitors using a hierarchical structure-based virtual screening strategy that combines molecular docking and the fragment molecular orbital method (FMO) for calculating binding affinity (referred to as the Dock-FMO protocol). For the SHP2 target, the FMO method prediction has a high correlation between the binding affinity of the protein-ligand interaction and experimental values (R2 = 0.55), demonstrating a significant advantage over the MM/PBSA (R2 = 0.02) and MM/GBSA (R2 = 0.15) methods. Therefore, we employed Dock-FMO virtual screening of ChemDiv database of ∼2,990,000 compounds to identify a novel SHP2 allosteric inhibitor bearing hydroxyimino acetamide scaffold. Experimental validation demonstrated that the new compound (E)-2-(hydroxyimino)-2-phenyl-N-(piperidin-4-ylmethyl)acetamide (7188-0011) effectively inhibited SHP2 in a dose-dependent manner. Molecular dynamics (MD) simulation analysis revealed the binding stability of compound 7188-0011 and the SHP2 protein, along with the key interacting residues in the allosteric binding site. Overall, our work has identified a novel and promising allosteric inhibitor that targets SHP2, providing a new starting point for further optimization to develop more potent inhibitors. METHODS: All the molecular docking studies were employed to identify potential leads with Maestro v10.1. The protein-ligand binding affinities of potential leads were further predicted by FMO calculations at MP2/6-31G* level using GAMESS v2020 system. MD simulations were carried out with AmberTools18 by applying the FF14SB force field. MD trajectories were analyzed using VMD v1.9.3. MM/GB(PB)SA binding free energy analysis was carried out with the mmpbsa.py tool of AmberTools18. The docking and MD simulation results were visualized through PyMOL v2.5.0.