Antagonistic Effects Research Articles

Ecological Stoichiometry of Multiple Nutrients in Leymus chinensis and Soils Subjected to Long-Term Saline-Sodic Stress in Western Jilin Province, China

L. chinensis is considered an important plant for saline-sodic soil restoration. Ecological stoichiometry of multiple nutrient elements in Leymus chinensis (L. chinensis) and soils subjected to long-term saline-sodic stress remains unclear, which hinders our understanding of the mechanisms regulating nutrient cycling in the plant-soil environment. We examined nutrient element levels in saline-sodic soil and L. chinensis in western Jilin Province. Soil analysis revealed medium to high levels of available N, K, P, Mo, Mn, Fe, Cu, and Zn. The Mn/Fe and N/P ratios exceeded the national soil average of China, while those of Fe/Cu, Fe/Zn, and P/K were comparatively lower. Furthermore, L. chinensis exhibited deficiencies in the Mn, Zn, and P. Mo/Mn, Mo/Zn, and Fe/Zn ratios, which were significantly higher compared to healthy plants, while Mn/Fe and P/K showed the opposite trend. Soil pH had the most significant effect on element stoichiometry in both the soil and in L. chinensis. Particularly, the soil available Mn, Zn, K, along with L. chinensis Mn, Fe, Cu, and P levels exhibited sensitivity to pH fluctuations. Additionally, we observed significant synergistic or antagonistic effects between the soil available element concentration and stoichiometry ratios. Among these, only Mn, Fe, Fe/Zn, Mo/Zn, N/K, and Mo/Fe in L. chinensis were significantly modeled (P < 0.05). The Mo/Fe homeostasis index was the lowest at 0.97, followed by Fe (1.16), N/K (2.28), Mo/Zn (2.59), Fe/Zn (3.38), and Mn (4.92), while other elements and their stoichiometric ratios remained stable. Overall, L. chinensis, as the dominant species in saline-sodic soil, demonstrated high homeostasis.

Synergistic activity of an RNA polymerase PA-PB1 interaction inhibitor with oseltamivir against human and avian influenza viruses in cell culture and in ovo

In search of novel therapeutic options to treat influenza virus (IV) infections, we previously identified a series of inhibitors that act by disrupting the interactions between the PA and PB1 subunits of the viral RNA polymerase. These compounds showed broad-spectrum antiviral activity against human influenza A and B viruses and a high barrier to the induction of drug resistance in vitro. In this short communication, we investigated the effects of combinations of the PA-PB1 interaction inhibitor 54 with oseltamivir carboxylate (OSC), zanamivir (ZA), favipiravir (FPV), and baloxavir marboxil (BXM) on the inhibition of influenza A and B virus replication in vitro. We observed a synergistic effect of the 54/OSC and 54/ZA combinations and an antagonistic effect when 54 was combined with either FPV or BXM. Moreover, we demonstrated the efficacy of 54 against highly pathogenic avian influenza viruses (HPAIVs) both in cell culture and in the embryonated chicken eggs model. Finally, we observed that 54 enhances OSC protective effect against HPAIV replication in the embryonated eggs model. Our findings represent an advance in the development of alternative therapeutic strategies against both human and avian IV infections.

Thermodynamic properties of β-HMX in binary mixed solvent systems and its microscopic mechanisms

Octogen (HMX) is the most powerful military explosive in current use. However, the unclear thermodynamic molecular mechanisms severely limit the development of its production process. In this paper, the solubility of β-HMX in three binary mixed solvent systems (acetone + ethanol, acetone + dichloromethane, acetone + toluene) was measured via a dynamic method at temperature ranging from 283.15 to 313.15 K under atmospheric pressure. The experimental results reveal that the solubility of β-HMX in these binary mixed solvent systems is positively correlated with acetone molar fraction and temperature, and the solvent composition has a greater impact on its solubility compared with the temperature. Moreover, the solubility of β-HMX is further correlated with the Van’t Hoff equation, modified Apelblat equation, CNIBS/R-K model, Jouyban-Acree-Van’t Hoff model, Jouyban-Acree-Apelblat model and NRTL model, and the modified Apelblat equation can give better fitting result (ARD = 8.101 × 10−3, RMSD = 1.065 × 10−5). Finally, the microscopic mechanism of the thermodynamic properties of β-HMX in binary mixed solvents is revealed by investigating the types, intensity and interaction sites of interactions based on density functional theory (DFT) and molecular dynamic (MD) simulation. The results demonstrate that both acetone molecules and ethanol molecules can form certain intermolecular interactions with β-HMX molecules, which are the main driving force of solubilization. In contrast, solvent–solvent interactions have an antagonistic effect on the solubility of β-HMX in mixed solvents. This work can further be informative for researchers in the field of energetic material for the solubility evaluations and provide a reference for the industrial production and performance enhancement of HMX in the future.

The Effect of Angiotensin II Type 1 Receptor Antagonist on Age-Related Differences in Renal Vascular Responses to Angiotensin II in Male and Female Rats.

Advancing age could influence renin angiotensin system components, especially angiotensin type 1 receptor (AT1R). This study examined the effect of AT1R antagonist, losartan, on age-related differences in renal vascular responses to angiotensin II in male and female rats. Forty-eight anesthetized male and female rats (8-12 and 24-28 weeks age ranges) were subjected to catheterize. Then, the responses of mean arterial pressure (MAP), renal perfusion pressure (RPP), renal blood flow (RBF), and renal vascular resistance (RVR) to angiotensin II with or without losartan were determined and evaluated. There were not significant differences in the basal values of MAP, RPP, RBF, and RVR in males. However, it was observed significant difference in RVR in females (P < 0.05). The blockade of AT1R attenuated basal MAP and RPP in all the groups (P < 0.05). The infusion of losartan altered basal RVR and RBF values in female groups (P < 0.05). Moreover, losartan eliminated vasoconstrictor responses to angiotensin II in female groups (P < 0.05). Also, losartan induced significant vascular responses to angiotensin II in male groups (P < 0.05). Losartan could maintain RBF changes in response to angiotensin II in both 8-12- and 24-28-week females. Losartan enhanced the RBF response to angiotensin II in 8-12-week males, but not in 24-28-week males. It seems that females (not males) in various age ranges are resistance against RBF changes by acutely increased angiotensin II.

GPR17 modulates anxiety-like behaviors via basolateral amygdala to ventral hippocampal CA1 glutamatergic projection

Anxiety disorders are one of the most epidemic and chronic psychiatric disorders. An incomplete understanding of anxiety pathophysiology has limited the development of highly effective drugs against these disorders. GPR17 has been shown to be involved in multiple sclerosis and some acute brain injury disorders. However, no study has investigated the role of GPR17 in psychiatric disorders. In a well-established chronic restraint stress (CRS) mouse model, using a combination of pharmacological and molecular biology techniques, viral tracing, in vitro electrophysiology recordings, in vivo fiber photometry, chemogenetic manipulations and behavioral tests, we demonstrated that CRS induced anxiety-like behaviors and increased the expression of GPR17 in basolateral amygdala (BLA) glutamatergic neurons. Inhibition of GPR17 by cangrelor or knockdown of GPR17 by adeno-associated virus in BLA glutamatergic neurons effectively improved anxiety-like behaviors. Overexpression of GPR17 in BLA glutamatergic neurons increased the susceptibility to anxiety-like behaviors. What's more, BLA glutamatergic neuronal activity was required for anxiolytic-like effects of GPR17 antagonist and GPR17 modulated anxiety-like behaviors via BLA to ventral hippocampal CA1 glutamatergic projection. Our study finds for the first and highlights the new role of GPR17 in regulating anxiety-like behaviors and it might be a novel potential target for therapy of anxiety disorders.

Adrenergic Agonists Activate Transcriptional Activity in Immortalized Neuronal Cells From the Mouse Suprachiasmatic Nucleus.

The suprachiasmatic nucleus of the hypothalamus (SCN) houses the central circadian oscillator of mammals. The main neurotransmitters produced in the SCN are γ-amino-butyric acid, arginine-vasopressin (AVP), vasoactive intestinal peptide (VIP), pituitary-derived adenylate cyclase-activating peptide (PACAP), prokineticin 2, neuromedin S, and gastrin-releasing peptide (GRP). Apart from these, catecholamines and their receptors were detected in the SCN as well. In this study, we confirmed the presence of β-adrenergic receptors in SCN and a mouse SCN-derived immortalized cell line by immunohistochemical, immuno-cytochemical, and pharmacological techniques. We then characterized the effects of β-adrenergic agonists and antagonists on cAMP-regulated element (CRE) signaling. Moreover, we investigated the interaction of β-adrenergic signaling with substances influencing parallel signaling pathways. Our findings have potential implications on the role of stress (elevated adrenaline) on the biological clock and may explain some of the side effects of β-blockers applied as anti-hypertensive drugs.

Optogenetics in oral and craniofacial research.

Optogenetics combines optics and genetic engineering to control specific gene expression and biological functions and has the advantages of precise spatiotemporal control, noninvasiveness, and high efficiency. Genetically modified photosensory sensors are engineered into proteins to modulate conformational changes with light stimulation. Therefore, optogenetic techniques can provide new insights into oral biological processes at different levels, ranging from the subcellular and cellular levels to neural circuits and behavioral models. Here, we introduce the origins of optogenetics and highlight the recent progress of optogenetic approaches in oral and craniofacial research, focusing on the ability to apply optogenetics to the study of basic scientific neural mechanisms and to establish different oral behavioral test models in vivo (orofacial movement, licking, eating, and drinking), such as channelrhodopsin (ChR), archaerhodopsin (Arch), and halorhodopsin from Natronomonas pharaonis (NpHR). We also review the synergic and antagonistic effects of optogenetics in preclinical studies of trigeminal neuralgia and maxillofacial cellulitis. In addition, optogenetic tools have been used to control the neurogenic differentiation of dental pulp stem cells in translational studies. Although the scope of optogenetic tools is increasing, there are limited large animal experiments and clinical studies in dental research. Potential future directions include exploring therapeutic strategies for addressing loss of taste in patients with coronavirus disease 2019 (COVID-19), studying oral bacterial biofilms, enhancing craniomaxillofacial and periodontal tissue regeneration, and elucidating the possible pathogenesis of dry sockets, xerostomia, and burning mouth syndrome.

Diallyl disulfide antagonizes DJ-1 mediated proliferation, epithelial-mesenchymal transition, and chemoresistance in gastric cancer cells.

Diallyl disulfide (DADS), an organic component of allicin abstracted from garlic, possesses multi-target antitumor activity. DJ-1 performs a vital function in promoting AKT aberrant activation via down-regulating phosphatase and tensin homologue (PTEN) in tumors. It is unknown the involvement of DJ-1 in epithelial-mesenchymal transition (EMT) of gastric cancer (GC) cells. The purpose of this study is to investigate whether diallyl disulfide (DADS) intervenes in the role of DJ-1 in GC. Based on the identification that the correlation between high DJ-1 and low PTEN expression in GC was implicated in clinical progression, we illuminated that down-regulation of DJ-1 by DADS aided in an increase in PTEN expression and a decrease in phosphorylated AKT levels, which was in line with the results manifested in the DJ-1 knockdown and overexpressed cells, concurrently inhibiting proliferation, EMT, migration, and invasion. Furthermore, the antagonistic effects of DADS on DJ-1 were observed in in vivo experiments. Additionally, DADS mitigated the DJ-1-associated drug resistance. The current study revealed that DJ-1 is one of potential targets for DADS, which hopefully provides a promising strategy for prevention and adjuvant chemotherapy of GC.

Enhancement of perpendicular magnetic anisotropy in NiMnSn/Co Heterostructures: Insights from PMOKE measurements

We investigated the magnetic properties of the Heusler alloy NiMnSn grown on thermally oxidized Si (100) by performing magnetic hysteresis measurements using the Polar Magneto-Optical Kerr Effect (PMOKE) technique. For a thickness of 30 nm, the NiMnSn alloy demonstrates out-of-plane magnetic anisotropy. We observed clear exchange bias, which we attribute to the exchange coupling between the spin glass and ferromagnetic phases. Our study also revealed that the growth of a 1 nm thick Heusler alloy NiMnSn layer on a cobalt layer with perpendicular anisotropy enhances the perpendicular magnetic anisotropy. However, we observed an antagonistic effect with thicker Heusler layers, resulting in a loss of perpendicular anisotropy and the appearance of an exchange bias (EB).

Insights into the antagonistic effects of calcium on cadmium accumulation in peanuts (Arachis hypogaea L.)

Peanut (Arachis hypogaea L.) plant has a high requirement for calcium (Ca) during its growth and development, and possesses the ability to accumulate cadmium (Cd) from soil. However, the precise mechanisms underlying the antagonistic effects between Ca and Cd remain unclear. This study aimed to explore the dynamic changes in Cd accumulation in peanut seedlings by varying the Ca-to-Cd concentration ratio (CRCa/Cd) from 250 to 3500. Additionally, the influence of ion channel competition and cell wall fixation in the root on Cd accumulation in peanuts was explored by analyzing Cd chemical forms, subcellular distribution, pectin content, and Cd2+ fluxes using a non-invasive micro-test technique (NMT). The findings revealed that Cd accumulation in peanut seedlings was significantly lower when the CRCa/Cd was higher than 2000. In the Ca-pretreated seedlings (cell wall fixation treatment), Cd content in the shoots and roots decreased by 18.9% and 25.0%, respectively, compared with the simultaneous exposure to Ca and Cd (ion channel competition treatment). Cd2+ influx in peanut roots decreased by 55.8% in the Ca-pretreated group. However, increasing the competitive strength of Ca2+ and Cd2+ did not affect Cd2+ influx under normal Ca conditions (>2 mM Ca). Meanwhile, Ca pretreatment significantly increased Cd distribution in the root cell wall, pectate, and protein-binding forms, while significantly reducing Cd distribution in root soluble components and inorganic Cd forms. The pectin content in the roots increased by 128% and 226% in the Ca and Cd simultaneous exposure treatment and Ca pretreatment, respectively. These results suggest that Ca pretreatment enhanced Cd retention in the root cell wall. Overall, exogenous Ca effectively mitigated Cd accumulation in peanut plants when the CRCa/Cd was below 2000, and Ca2+ channels partially facilitate the entry of Cd2+ into peanut roots. Under normal Ca supply conditions, exogenous Ca reduced Cd accumulation in peanuts primarily through root cell wall fixation rather than ion channel competition. Our findings provide insights into the mechanism by which Ca alleviates the uptake and transfer of Cd in peanuts.

A strategy for the efficient removal of acidic and basic dyes in wastewater by organophilic magadiite@alginate beads: Box-Behnken Design optimization

In this study, four adsorbents were developed: layered silicate magadiite material (mag), Hexadecyltrimethylammonium intercalated magadiite (HDTMA@mag), a cross-linked composite of sodium alginate and magadiite (ALG@mag) and a cross-linked composite of sodium alginate and HDTMA@magadiite (ALG@HDTMA@mag). The adsorbents were evaluated for their effectiveness in removing of Methylene Blue (MB) and Eriochrome Black T (EBT) dyes. The prepared adsorbents were characterized using SEM, XRD, FTIR, and zeta potential measurements. Kinetic modeling results indicated that both film diffusion and intraparticle diffusion are useful as rate-determining processes in adsorption for all adsorbents. For both dyes, the Langmuir isotherm model provided a good correlation with the adsorption equilibrium data. ANOVA analysis for the best adsorbent (ALG@HDTMA@mag beads) revealed that MB removal was significantly influenced by the positive individual effects of contact time and ALG@HDTMA@mag dose. However, the individual effect of MB concentration exhibited an antagonistic effect throughout the adsorption process. The optimal parameters for achieving an adsorption capacity of 118.54 mg/g were a dye concentration of 60 ppm, a contact period of 1800 min, and an ALG@HDTMA@mag dose of 50 mg.

A N‐Cadherin Nano‐Antagonist Hydrogel Enhances Recovery From Spinal Cord Injury by Impeding Glial Scarring

AbstractThe role of glial scars in the pathophysiology of spinal cord injury (SCI) is widely recognized, as they pose physical barriers against axonal regeneration and persistent chronic inflammation by releasing cytotoxic agents, thereby impeding nerve repair. Consequently, preventing glial scarring has emerged as an important therapeutic objective in SCI management. Following SCI, astrocytes undergo a phenotypic transition into scar‐forming astrocytes, which critically depends on the activation of inflammatory responses and the integrin‐N‐cadherin pathway. To explore improved SCI treatment, a nano‐antagonist hydrogel (Nano‐ant Gel), comprising N‐cadherin nano‐antagonists and a polyphenol hydrogel designed to inhibit glial scarring by mitigating inflammatory response and modulating astrocyte behavior, thereby facilitating spinal cord‐injury repair, is developed and characterized. The hydrogel exhibits notable anti‐inflammatory properties, specific calcium ion‐adsorption capabilities, and antagonistic effects against N‐cadherin, effectively impeding the formation and aggregation of scar‐forming astrocytes. Its efficacy is comprehensively assessed using a model of contusive SCI, with which it effectively inhibits glial scar formation and promotes axonal regeneration. Notably, the Nano‐ant Gel significantly improves the locomotor functions of mice with SCI, suggesting that it represents a promising approach for treating the condition.

Augmentative effects of leukemia inhibitory factor reveal a critical role for TYK2 signaling in vascular calcification

Medial vascular calcification in chronic kidney disease (CKD) involves pro-inflammatory pathways induced by hyperphosphatemia. Several interleukin 6 family members have been associated with pro-calcific effects in vascular smooth muscle cells (VSMCs) and are considered as therapeutic targets. Therefore, we investigated the role of leukemia inhibitory factor (LIF) during VSMC calcification. LIF expression was found to be increased following phosphate exposure of VSMCs. LIF supplementation aggravated, while silencing of endogenous LIF or LIF receptor (LIFR) ameliorated the pro-calcific effects of phosphate in VSMCs. The soluble LIFR mediated antagonistic effects towards LIF and reduced VSMC calcification. Mechanistically, LIF induced phosphorylation of the non-receptor tyrosine-protein kinase 2 (TYK2) and signal transducer and activator of transcription-3 (STAT3) in VSMCs. TYK2 inhibition by deucravacitinib, a selective, allosteric oral immunosuppressant used in psoriasis treatment, not only blunted the effects of LIF, but also interfered with the pro-calcific effects induced by phosphate. Conversely, TYK2 overexpression aggravated VSMC calcification. Ex vivo calcification of mouse aortic rings was ameliorated by Tyk2 pharmacological inhibition and genetic deficiency. Cholecalciferol-induced vascular calcification in mice was improved by Tyk2 inhibition and in the Tyk2-deficient mice. Similarly, calcification was ameliorated in Abcc6/Tyk2-deficient mice after adenine/high phosphorus-induced CKD. Thus, our observations indicate a role for LIF in CKD-associated vascular calcification. Hence, the effects of LIF identify a central pro-calcific role of TYK2 signaling, which may be a future target to reduce the burden of vascular calcification in CKD.

Taxonomic characterization and secondary metabolite production of newly isolated Streptomyces sp. MC12

An actinobacterium newly isolated from soil during a screening study was identified as Streptomyces sp. MC12 (GenBank accession number: PP757795) based on 16S rRNA analysis. For secondary metabolite production, fermentation was carried out in ISP 2 broth at 30°C, pH 7.3, for seven days under shaking conditions at 180 rpm. As a result of fermentation studies, the antagonistic effect of the crude extract, obtained through ethyl acetate extraction, against various microorganisms was determined. The MIC values of the extract against Staphylococcus aureus and Escherichia coli were 101.3 µg/mL and 153.6 µg/mL, respectively. It was also found to exhibit strong antifungal activity against Penicillium spp. Streptomyces sp. MC12, which displays both antifungal and antibacterial properties, is considered a potential secondary metabolite producer for future studies, particularly in pharmacology and the biocontrol of fungal pathogens.

Core microbiome-associated proteins associated with ulcerative colitis interact with cytokines for synergistic or antagonistic effects on gut bacteria.

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is associated with a loss or an imbalance of host-microorganism interactions. However, such interactions at protein levels remain largely unknown. Here, we applied a depletion-assisted metaproteomics approach to obtain in-depth host-microbiome association networks of IBD, where the core host proteins shifted from those maintaining mucosal homeostasis in controls to those involved in inflammation, proteolysis, and intestinal barrier in IBD. Microbial nodes such as short-chain fatty-acid producer-related host-microbial crosstalk were lost or suppressed by inflammatory proteins in IBD. Guided by protein-protein association networks, we employed proteomics and lipidomics to investigate the effects of UC-related core proteins S100A8, S100A9, and cytokines (IL-1β, IL-6, and TNF-α) on gut bacteria. These proteins suppressed purine nucleotide biosynthesis in stool-derived in vitro communities, which was also reduced in IBD stool samples. Single species study revealed that S100A8, S100A9, and cytokines can synergistically or antagonistically alter gut bacteria intracellular and secreted proteome, with combined S100A8 and S100A9 potently inhibiting beneficial Bifidobacterium adolescentis. Furthermore, these inflammatory proteins only altered the extracellular but not intracellular proteins of Ruminococcus gnavus. Generally, S100A8 induced more significant bacterial proteome changes than S100A9, IL-1β, IL-6, and TNF-α but gut bacteria degrade significantly more S100A8 than S100A9 in the presence of both proteins. Among the investigated species, distinct lipid alterations were only observed in Bacteroides vulgatus treated with combined S100A8, S100A9, and cytokines. These results provided a valuable resource of inflammatory protein-centric host-microbial molecular interactions.

Antagonistic Effects and the Underlying Mechanisms of Bacillus velezensis and its Antibacterial Peptide LCI Against Aeromonas hydrophila Infection in Largemouth Bass.

Aeromonas hydrophila is one of the most prevalent pathogenic bacteria in largemouth bass. The use of antibiotics to inhibit A. hydrophila poses a significant threat to fish and environmental safety. Bacillus velezensis, a safe bacterium with probiotic and antibacterial characteristics, is an ideal candidate for antagonizing A. hydrophila. This study explored the antagonistic effects of B. velezensis FLU-1 on A. hydrophila in vivo and in vitro. In addition, we explored the antimicrobial peptides (AMPs) produced by strain FLU-1 and clarified the underlying antibacterial mechanisms. The results showed that strain FLU-1 could inhibit a variety of fish pathogens, including A. hydrophila. The challenge test showed that dietary supplementation with B. velezensis FLU-1 significantly improved the survival rate of largemouth bass and reduced the bacterial load in liver. Subsequently, the AMP LCI was isolated from B. velezensis FLU-1 and was found to be effective against A. hydrophila in vitro and in vivo. Transcriptomic analysis revealed that LCI downregulated the genes associated with flagellar assembly and peptidoglycan synthesis in A. hydrophila. Phenotypic test results showed that LCI disrupted the membrane integrity, markedly reduced the biofilm biomass and diminished the swimming motility of A. hydrophila. Furthermore, the results showed that LCI bound to the genomic DNA of A. hydrophila and destroyed the DNA structures. Overall, these findings elucidated the mechanism of action of LCI against A. hydrophila at the phenotypic and physiological levels. This study suggests that B. velezensis FLU-1 and its AMP LCI could serve as antibiotic alternatives for controlling pathogens in aquaculture.

Insight into response mechanism of aerobic granular sludge to combined nanoparticle stress: Nitrogen removal, microbial community and heavy metal resistance genes

Multiple nanoparticles presented in wastewater treatment plants can produce comprehensive ecotoxicity. In this study, copper oxide nanoparticles (nCuO) and zinc oxide nanoparticles (nZnO) were investigated for their co-toxicity to aerobic granular sludge (AGS) systems. The combined stress of nCuO and nZnO performed significant antagonistic effects on nitrogen removal both under acute and chronic stress. Under chronic stress, nCuO and nZnO co-existence performed significant antagonistic effects on cell membrane, adenosine triphosphate (ATP) activity and microbial community structure. PICRUSt analysis indicated that nCuO (15 mg/L) co-existence alleviated nZnO (10 mg/L) inhibition on energy production and membrane transport metabolic pathways. In addition, nCuO addition to single nZnO weakened the toxicity of nZnO to nitrogen metabolism, glucose metabolism, and electron transfer genes, contributing to an alleviation in nitrogen removal inhibition. As compared with individual stress, combined stress decreased Cu(II) release from nCuO, but increased Zn(II) release from nZnO. The combination of nCuO and nZnO increased zinc resistance gene amplification and czcC gene proportion, and promoted Zn(II) efferent from cells, also with AGS resistance.

Anticancer Potential of Valencia Peanut (Arachis hypogaea L.) Skin Extract against Cervical Cancer Cells In Vitro and in Nude Mouse Xenograft Models.

This study investigated the impact of Valencia KK4-type peanut skin ethanolic extract (KK4-PSE) combined with cisplatin or 5-fluorouracil (5-FU) on HeLa cells in vitro and in xenograft models. At exposure times of 24, 48 and 72 h, KK4-PSE inhibited the growth of HeLa cells with a half maximal inhibitory concentration (IC50) of 79.43 ± 0.54, 55.55 ± 1.57 and 41.32 ± 0.74 µg/mL, respectively. Drug interactions evaluated by the Chou-Talalay method demonstrated that KK4-PSE enhanced antiproliferative activity of 5-FU against HeLa cells with combination index (CI) values of 0.49 (48 h) and 0.60 (72 h), indicating a synergistic effect, while KK4-PSE combined with cisplatin exhibited an additive effect (CI = 1.02) at 72 h, and an antagonistic effect at 24 and 48 h exposures (CI = 1.12 and 1.18, respectively). In nude mouse xenograft models, the combination of 5-FU and KK4-PSE markedly reduced HeLa tumor weights compared with the control and single agent treatments groups. The combination of KK4-PSE and 5-FU achieved greater tumor growth inhibition than that of the KK4-PSE-cisplatin combination. KK4-PSE mitigated hepatotoxicity induced by both cisplatin and 5-FU in nude mice. The spleen hyaloserositis was significantly reduced in the combination treatment of 5-FU and KK4-PSE. These results suggest that KK4-PSE has the potential to limit cervical cancer cell proliferation while reducing the toxicity of cisplatin and 5-FU.

Prediction of Endocrine-Disrupting Chemicals Related to Estrogen, Androgen, and Thyroid Hormone (EAT) Modalities Using Transcriptomics Data and Machine Learning.

Endocrine-disrupting chemicals (EDCs) are chemicals that can interfere with homeostatic processes. They are a major concern for public health, and they can cause adverse long-term effects such as cancer, intellectual impairment, obesity, diabetes, and male infertility. The endocrine system is a complex machinery, with the estrogen (E), androgen (A), and thyroid hormone (T) modes of action being of major importance. In this context, the availability of in silico models for the rapid detection of hazardous chemicals is an effective contribution to toxicological assessments. We developed Qualitative Gene expression Activity Relationship (QGexAR) models to predict the propensities of chemically induced disruption of EAT modalities. We gathered gene expression profiles from the LINCS database tested on two cell lines, i.e., MCF7 (breast cancer) and A549 (adenocarcinomic human alveolar basal epithelial). We optimized our prediction protocol by testing different feature selection methods and classification algorithms, including CATBoost, XGBoost, Random Forest, SVM, Logistic regression, AutoKeras, TPOT, and deep learning models. For each EAT endpoint, the final prediction was made according to a consensus prediction as a function of the best model obtained for each cell line. With the available data, we were able to develop a predictive model for estrogen receptor and androgen receptor binding and thyroid hormone receptor antagonistic effects with a consensus balanced accuracy on a validation set ranging from 0.725 to 0.840. The importance of each predictive feature was further assessed to identify known genes and suggest new genes potentially involved in the mechanisms of action of EAT perturbation.

PREDICTION OF THE INTERACTION MECHANISMS OF QUERCETIN, Α-CYPERMETHRIN AND ITS DERIVATIVES WITH THE Α-ESTROGEN RECEPTOR (IN SILICO STUDY)

Introduction. Excessive use of pesticides leads to environmental pollution and poses a danger to human and animal health. Pyethroid insecticides (pyrethroids) are the most commonly used pesticides because they are less toxic to non-target species. It is well-known that prolonged exposure to pyrethroids can result in the endocrine function of the gonads being disrupted. Cypermethrin is a very common pyrethroid, the toxicity of which is widely studied, but little is known about the endocrine-disrupting effect of its stereoisomer, α-cypermethrin. In our opinion, quercetin, a flavonoid that has estrogen-like and antioxidant properties, can be an effective means of protection against the complications of pyrethroid intoxication. Aim. In silico studies of the binding mechanisms of quercetin, α-cypermethrin and its derivatives with the estrogen receptor α, features of pharmacokinetics and toxicity profile of these compounds. Methods. The molecular docking procedure of quercetin, α-cypermethrin, 3-PВA and DCCA was carried out using the crystal structures of the ligand-binding domain of ERα: 3ERT (reference ligand – 4-hydroxytamoxifen), 1ERR (reference ligand – raloxifene), 1GWR and 1ERE (reference ligand – estradiol) from the PDB database of biological macromolecules. Three different docking software packages were used: Glide, AutoDock, and AutoDock Vina. The location of the reference ligand was used to determine the automatic detection of the binding site. The pkCSM platform, admetSAR online server and SwissADME were used for in silico investigation of pharmacokinetic properties and toxicity of quercetin and α-cypermethrin. The results. AutoDock predicts that α-cypermethrin has the lowest binding energy with 1ERE (–10.4 kcal/mol), 1GWR (–10.0 kcal/mol), and 1ERR. This may indicate an agonistic effect of this insecticide on ERα. The predicted Gscore values for α-cypermethrin reflect a stronger interaction with 3ERT: –9.29 kcal/mol. The binding characteristics of α-cypermethrin, its metabolites (3-PBA and DCCA) and 4-hydroxytamoxifen with 3ERT are similar, which may indicate an antagonistic effect of the pyrethroid for ERα. The opposite nature of the interaction of α-cypermethrin with ERα can be explained by the difference in evaluation functions and methods of optimization of protein structures and ligands depending on the software used. The results predicted by both AutoDock, Vina and Schrödinger Maestro Glide show for quercetin the lowest binding energy values with 1ERR, 1GWR and 1ERE, which is a sign of agonistic action. Quercetin binds to the ligand-binding domains of ERα more strongly than 3-PBA and DCCA. Quercetin has toxicity and pharmacokinetic parameters corresponding to the norm and meets all the requirements for drug-like properties. Based on the data obtained in silico, it is possible to assert the expediency of using quercetin as a component of the prevention of complications of the endocrinotoxic action of α-cypermethrin. Conclusions. The toxic effect of α-cypermethrin, which is aimed at disrupting the endocrine function of the gonads, may be associated with the high affinity of this compound and its metabolites for ERα, accompanied by both agonistic and antagonistic effects according to various evaluation criteria. Quercetin, a flavonoid with pronounced ER agonistic properties, can be used to prevent complications of α-cypermethrin intoxication based on its pharmacokinetic and drug-like parameters.