P-glycoprotein Research Articles

Fecal carriage of ESBL-producing E. coli and genetic characterization in rural children and livestock in the Somali region, Ethiopia: a one health approach

BackgroundThe emergence and spread of Extended-Spectrum Beta-Lactamase (ESBL)-producing Escherichia coli pose significant challenges for treatment of infections globally. This challenge is exacerbated in sub-Saharan African countries, where the prevalence of ESBL-producing E. coli is high. This, combined with the lack of a strong and supportive healthcare system, leads to increased morbidity and mortality due to treatment failures. Notably, studies in Ethiopia have primarily focused on hospital settings, leaving a gap in understanding ESBL prevalence in rural communities, where human-animal proximity may facilitate microbial exchange.MethodsWe conducted a community-based study in the rural Somali region of Ethiopia, simultaneously examining the fecal carriage of ESBL-producing E. coli in children aged 2–5 years and their livestock (cattle, camel, goat). Fecal samples from 366 children and 243 animals underwent phenotypic screening for ESBL-producing E. coli. Following phenotypic confirmation, ESBL resistance genes were identified via conventional PCR. Whole-genome sequencing (WGS) was performed on a subset of isolates from human feces.ResultsWe found that 43% (159/366) of children and 3.7% (9/244) of livestock harbored ESBL-producing E. coli. The ESBL gene blaCTX-M-15 was predominant in human (82.7%, 120/145) and livestock (100%) isolates. In the 48 human E. coli isolates subjected to WGS, a high diversity resulting in 40 sequence types (STs) was observed. Among these, ST-2353 was the most prevalent (5/48), followed by ST-10 and ST-48 (3/48) and ST-38, ST-450, and ST-4750 (2/48). These STs were associated with multiple resistance genes, such as blaCTX-M-15, blaTEM-1B, blaOXA-1, blaCTX-M-14 and blaTEM-35.ConclusionWe report a high prevalence of ESBL E. coli in rural children, which outnumbers its prevalence in livestock. These isolates displayed a high diversity of sequence types (STs) with ST-2353 being the dominant ST. Our study is the first to report the association of ST-2353 with multi-drug resistance genes in Ethiopia. Further research using an integrated approach including other domains such as water and food products is needed to truly understand and combat AMR transmission and acquisition in this region.

Resistome in the indoor dust samples from workplaces and households: a pilot study.

The antibiotic resistance genes (ARGs) limit the susceptibility of bacteria to antimicrobials, representing a problem of high importance. Current research on the presence of ARGs in microorganisms focuses mainly on humans, livestock, hospitals, or wastewater. However, the spectrum of ARGs in the dust resistome in workplaces and households has gone relatively unexplored. This pilot study aimed to analyze resistome in indoor dust samples from participants' workplaces (a pediatric hospital, a maternity hospital, and a research center) and households and compare two different approaches to the ARGs analysis; high-throughput quantitative PCR (HT-qPCR) and whole metagenome shotgun sequencing (WMGS). In total, 143 ARGs were detected using HT-qPCR, with ARGs associated with the macrolides, lincosamides, and streptogramin B (MLSB) phenotype being the most abundant, followed by MDR (multi-drug resistance) genes, and genes conferring resistance to aminoglycosides. A higher overall relative quantity of ARGs was observed in indoor dust samples from workplaces than from households, with the pediatric hospital being associated with the highest relative quantity of ARGs. WMGS analysis revealed 36 ARGs, of which five were detected by both HT-qPCR and WMGS techniques. Accordingly, the efficacy of the WMGS approach to detect ARGs was lower than that of HT-qPCR. In summary, our pilot data revealed that indoor dust in buildings where people spend most of their time (workplaces, households) can be a significant source of antimicrobial-resistant microorganisms, which may potentially pose a health risk to both humans and animals.

Dairy farm waste: a potential reservoir of diverse antibiotic resistance and virulence genes in aminoglycoside- and beta-lactam-resistant Escherichia coli in Gansu Province, China

Aminoglycosides (AGs) and beta-lactams are the most commonly used antimicrobials in animal settings, particularly on dairy farms. Dairy farm waste is an important reservoir of antibiotic resistance genes (ARGs) and virulence genes (VGs) in environmental Escherichia coli, which is an important indicator of environmental contamination and foodborne pathogen that potentially threaten human and animal health. In the present study, we aimed to characterize the ARGs and VGs in AG- and beta-lactam-resistant E. coli from dairy farm waste in Gansu Province, China. The dairy farm waste consisted of fecal (n=265) and sewage (n=54) samples processed using standard microbiological techniques and the Clinical & Laboratory Standards Institute guidelines. The total DNA of AG- and beta-lactam-resistant E. coli was extracted, and whole-genome sequencing (WGS) was performed using the Illumina NovaSeq platform and analyzed using various bioinformatics tools. In this study, among 84.3% (269/319) of the E. coli strains, 23.8% (64/269) were identified as AG- and beta-lactam-resistant E. coli. WGS analysis revealed a large pool of ARGs belonging to multiple classes such as AGs, beta-lactams, aminocoumarins, fluoroquinolones, macrolides, phenicol, tetracyclines, phosphonic acid, disinfecting and antiseptic agents, elfamycin, rifamycin, and multidrug resistance genes. Furthermore, virulome analysis of 64 E. coli strains revealed clinically important virulence factors associated with adherence, biofilm, invasion, auto-transportation, siderophores, secretion systems, toxins, anti-phagocytosis, quorum sensing, regulation, metabolism, and motility. We identified dairy farm feces and sewage waste as important reservoirs of antimicrobial resistance and virulence determinants in E. coli in Gansu, China, which can threaten human and animal health through ecological exposure and ingestion of contaminated food and water. We recommend continuous large-scale surveillance in dairy farm settings to formulate protective guidelines for public health safety.

Deciphering basic and key traits of bio-pollutants in a long-term reclaimed water headwater urban stream.

Reclaimed water has been recognized as a stable water resource for ecological replenishment in riverine environment. However, information about the bio-pollutants spatial and temporal distributions and the associated risk in this environment remains insufficient. Herein, the bio-pollutant profile in a long-term reclaimed water headwater urban stream, including antibiotic resistance genes (ARGs), mobile genetic elements and pathogens, were revealed by metagenomics. Notably, the temporal variation in bio-pollutant levels exceeded spatial fluctuations, possibly due to the varied rainfall intensity. Specially, multidrug resistance genes and Acinetobacter baumannii (A. baumannii) were the dominant ARGs and pathogens, respectively, exhibiting higher abundance in the dry season, especially in the downstream of the receiving point, where the bio-risk also peaked. A. baumannii and Ralstonia solanacearum were found to be the main plasmids contributors inducing the horizontal gene transfer process in this stream. Overall, A. baumannii contributed over 50% bio-risk values in most samples, indicating that it was the "overlord" in this headwater urban stream. This study revealed characteristics of bio-pollutants in a typical long-term reclaimed water headwater urban stream, highlighting the superiority of A. baumannii in bio-pollutants, which should be a key consideration in the bio-pollutants surveillance for reclaimed waters.

Synergistic anticancer efficacy of polydatin and sorafenib against the MCF-7 breast cancer cell line via inhibiting of PI3K/AKT/mTOR pathway and reducing resistance to treatment

Polydatin (PD), a glucoside derivative of resveratrol, has been investigated for its potential to mitigate sorafenib (SOF) side effects and combat multidrug resistance in cancer treatment. The study evaluated its mechanism of action for inhibiting the protein kinase B/mTOR pathway in promoting breast cancer proliferation. The combined PD and SOF have synergistic effects with a combination index (CI) < 1 in the liver (HepG2) and breast (MCF-7) cancer cell lines. Molecular docking studies were conducted to analyze interactions of PD& SOF with protein kinases as well as apoptotic and multidrug resistance proteins, including AKT1, PI3K, mTOR, Apaf-1, and ABCB1 in MCF-7 cells. Experimental validation through real-time PCR confirmed. PD has a strong binding affinity, particularly with AKT1 (-56 kcal/mol) and ABCB1 (-27.16 kcal/mol), a gene associated with multidrug resistance. These interactions were linked to anti-proliferative anti-angiogenic effects and reduced resistance to treatment, demonstrating PD has potential therapeutic benefits. Furthermore, PD combined with SOF induced apoptosis, inhibited cell growth, and arrested MCF-7 cells in the sub-G1 phase with increased intracellular ROS. This was accompanied by reduced expression of AKT1 and ABCB1 genes, reinforcing the anticancer efficacy of PD/SOF combination therapy. In conclusion, the findings suggest that PD/SOF could serve as a promising anticancer treatment strategy, warranting further investigation for potential clinical applications and mechanistic studies in vivo.

Draft genome sequence of a co-harbouring blaNDM-5 and mcr-1.1 Escherichia coli phylogroup A isolate associated with patient colonisation in Ireland.

ObjectivesWhile Escherichia coli phylogroup-A is typically associated with commensal strains, some isolates can harbour virulence and exhibit multidrug-resistant (MDR) phenotypes. We report the draft genome of a rare instance of carbapenem, fosfomycin and colistin resistant E. coli phylogroup-A, isolated as part of routine screening of a human patient in a clinical setting in Ireland. MethodsE. coli E230738 was identified using MALDI-ToF/MS. Antibiotic susceptibility testing was performed using the Sensitire-EUMDRXXF plate. Whole-genome-sequencing was conducted with NextSeq1000, and genomic analysis identified antibiotic-resistance-genes (ARGs) and virulence-factors (VFs). Phylogenetic analysis was performed using whole-genome-multilocus-sequence-typing (wgMLST). ResultsE. coli E230738 genome was identified to belong to phylogroup-A/ST10 complex and to harbour 63 ARGs (17 acquired). Resistance to beta-lactams, including carbapenems and cephalosporins was likely due to predicted chromosomal blaNDM-5. Colistin resistance appeared associated with acquired mcr-1.1. Despite lacking fosfomycin-inactivating-enzymes, fosfomycin resistance was observed, possibly due to efflux pumps. 47 chromosomal VFs were identified, involved in adhesion and iron acquisition amongst others. Plasmid replicons associated with the spread of MDR genes such as IncHI2/HI2A were detected. Phylogenetic analysis showed the closest relative being a strain from the UK differing by 851 genes. ConclusionThis is a first detected instance of a blaNDM-5 and mcr-1.1 co-occurring in E. coli in Ireland. The MDR profile of E. coli E230738 highlights the growing public health threat posed by the dissemination of MDR E. coli lineages with limited treatment options and underscores the need for clinical screening coupled with genomic surveillance to better understand evolving MDR patterns in E. coli.

Metatranscriptomic Analysis Reveals Actively Expressed Antimicrobial-Resistant Genes and Their Hosts in Hospital Wastewater

Antimicrobial resistance is a major global concern and economic threat, necessitating a reliable monitoring approach to understand its frequency and spread via the environment. Hospital wastewater serves as a critical reservoir for antimicrobial-resistant organisms; however, its role in resistance gene distribution and dissemination remains poorly understood. This study integrates metagenomic and metatranscriptomic analyses, elucidating the dynamics of antimicrobial resistance in hospital wastewater. Integrated metagenomic and metatranscriptomic sequencing were used to identify actively expressed antimicrobial-resistant genes and antimicrobial-resistant bacteria, offering comprehensive insights into antimicrobial resistance dynamics in hospital wastewater. Liquid chromatography–tandem mass spectrometry analysis revealed the presence of ampicillin, sulbactam, levofloxacin, sulfamethoxazole, and trimethoprim in the sample, which could apply selective pressure on antimicrobial resistance gene expression. While multidrug resistance genes were the most prevalent sequences in both metagenome-assembled genomes and plasmids, plasmid-derived sequences showed a high mRNA/DNA ratio, emphasizing the presence of functionally expressed antimicrobial resistance genes on plasmids rather than on chromosomes. The metagenomic and metatranscriptomic analyses revealed Serratia nevei MAG14 with high mRNA levels of antimicrobial resistance genes; moreover, multidrug-resistant Serratia sp., genetically related to MAG14, was isolated from the wastewater, supporting the phenotypic characterization of crucial antimicrobial-resistant bacteria and validating the genome analysis results. The findings underscore key genes and bacteria as targets for antimicrobial resistance surveillance in hospital wastewater to protect public and environmental health.

Impact of genetic variants on fentanyl metabolism in major breast surgery patients: a candidate gene association study.

The study aimed to examine the association of two selected candidate SNPs rs2242480 (CYP3A4) and rs1045642 (ABCB1) with metabolic ratio of plasma norfentanyl to fentanyl concentrations in patients undergoing major breast surgeries. The retrospective cross-sectional study was done in 257 female patients. DNA extraction, genotyping of selected SNPs, and drug levels measurement were employed. A total of 257 female patients were recruited with no loss to follow up. There was no significant association between the two mentioned SNPs and the metabolic ratio (p value > 0.05). As an exploratory analysis, there was a moderately significant negative correlation between metabolic ratio and pupillary constriction to fentanyl (r = -0.27; p < 0.001). There was also a weak but significant positive correlation between metabolic ratio and time for first analgesia in the postoperative period (r = 0.17; p = 0.01). There was no significant association with the selected candidate SNPs in CYP3A4 and ABCB1 genes and metabolic ratio of norfentanyl to fentanyl in South Indian patients undergoing major breast surgery.

Lung cancer, platinum analog-based frontline treatment and pharmacogenetic limitations.

Lung cancer has the highest mortality rate among all the highly prevalent neoplasia globally. The major concern with its frontline treatment-cisplatin, is the rapid progression of chemoresistance and multi-organ-based toxicities including hearing loss and tinnitus, nephrotoxicity, hepatotoxicity and myelosuppression including anemia and neutropenia. In this review, studies concluding the association of single nucleotide polymorphisms (SNP) in disparate genes with aforementioned toxicity points are summarized to observe the pharmacogenomic pattern. Especially, SNPs in ATP7B, ERCC-1, ERCC-2, MATE-1, OCT-2, ABCB-1, ABCC-1, ABCG-2, ABCC-2, SLC22A, ERCC-5, BRCA-1, GSTM-3, GSTM-4 and GSTM-5 genes appear to be associated with the therapeutic response and/or adverse effects of cisplatin. We recommend utilizing this information to minimize the risk of treatment failure due to chemoresistance and adverse effects on other organs.

Population pharmacokinetic study of the effect of polymorphisms in the ABCB1 and CES1 genes on the pharmacokinetics of dabigatran.

The impact of genetic polymorphisms in the ABCB1 and CES1 genes on dabigatran plasma concentrations remains a subject of debate, and the purpose of this study was to quantitatively assess the effects of genetic polymorphisms on dabigatran esters in healthy Chinese subjects employed a population pharmacokinetic (PopPK) approach. In total, 1,926 pharmacokinetic (PK) samples from 123 healthy individuals who were given 150mg of dabigatran orally during a fasting state or postprandially were analyzed using the PopPK model. A two-compartment model with first-order absorption was found to adequately describe the PK data. The results showed that covariates food intake and ABCB1 SNP rs4148738 were shown to have statistically significant impacts. Specifically, in postprandial administration increased lag time (ALAG) and clearance (CL) by 2.65% and 0.51%, respectively, and decreased absorption rate constant (KA) by 0.24%. Additionally, in subjects with CT genotype ABCB1 (rs4148738), the central ventricular volume of distribution (V2) was increased by 0.38%. In summary, the PopPK model developed in this study was robust and effectively characterized the pharmacokinetics of dabigatran in healthy Chinese adults, demonstrating that both food and ABCB1 genetic variation significantly influence the absorption and plasma concentration levels of dabigatran.

Analysis of multidrug resistance gene locus mutations and clinical significance in children with Mycoplasma pneumoniae pneumonia

To detect multidrug resistance gene locus mutations in children with Mycoplasma pneumoniae pneumonia through targeted high-throughput sequencing and to explore its clinical significance. A retrospective analysis was conducted on the clinical data of 2 899 children with Mycoplasma pneumoniae pneumonia, who underwent respiratory pathogen-targeted high-throughput sequencing, treated at Hubei Maternal and Child Health Care Hospital between January and December 2023. The patients were divided into a mutation group (n=885) and a non-mutation group (n=2 014) based on whether there was a mutation in the 23SrRNA macrolide-resistant gene of Mycoplasma pneumoniae. Multivariate logistic regression analysis was used to investigate the risk factors for multidrug resistance gene locus mutations in children with Mycoplasma pneumoniae pneumonia. Among the 2 899 children, 885 cases (30.53%) had mutations in the 23SrRNA resistance gene, including 884 cases with the A2063G mutation and 1 case with the A2064G mutation. In children with 23SrRNA resistance gene mutations, treatment with doxycycline or ofloxacin was more effective than with azithromycin or clarithromycin, and doxycycline was more effective than ofloxacin (P<0.05). The mutation rate of resistance genes in children with Mycoplasma pneumoniae pneumonia increased with age (P<0.001). Multivariate logistic regression analysis showed that increased age, extrapulmonary infection, lung consolidation, prolonged fever, prolonged hospitalization, and elevated CRP levels were risk factors for 23SrRNA gene locus mutations (P<0.05). Age, extrapulmonary infections, lung consolidation, duration of fever, length of hospitalization, and CRP levels are closely related to 23SrRNA resistance gene locus mutations. Detecting multidrug resistance gene locus mutations in children with Mycoplasma pneumoniae pneumonia can aid in early diagnosis and prediction of treatment efficacy, promoting rational clinical treatment.

ABC Family Gene Polymorphisms and Cognitive Functions Interact to Influence Antidepressant Efficacy.

The importance of identifying relevant indicators of antidepressant efficacy is highlighted by the low response rates to antidepressant treatment for depression. The ABC gene family, encoding ATP-dependent transport proteins facilitating the transport of psychotropic drugs, has drawn attention. This study delved into the relationship between antidepressant efficacy and seven single nucleotide polymorphisms of ABCB1 and ABCB6 genes. A total of 549 depressed patients participated in the study, and all completed a 6-week course of antidepressant treatment. Cognitive function was assessed at baseline and post-treatment. Patients were categorized based on post-treatment HAMD-17 scores (with HAMD≤7 indicating remission), and comparisons were made between different groups in terms of allelic gene frequencies and genotypes. Logistic regression was used to explore the interaction between cognitive function and genotype on efficacy. Dual-luciferase reporter assays were performed to compare the regulatory effects of rs1109866 allele variants on the ABCB6 promoter. There were no notable differences in allelic gene frequencies and genotypes between the remission and non-remission groups. Nonetheless, a significant interaction was identified between the rs1109866 genotype and language fluency-related indicators concerning efficacy (p=0.029) before correction. The dual-luciferase reporter assays demonstrated markedly higher fluorescence intensity of rs1109866-C compared to that of rs1109866-T (p<0.001). Relying solely on genetic polymorphisms of ABC family genes as predictors of antidepressant treatment response may not be sufficient. However, the interaction between the rs1109866 and cognition plays a pivotal role. The potentially enhanced transcriptional activity of rs1109866-C might offer insight into its impact on antidepressant efficacy.

Solasodine Downregulates ABCB1 Overexpression in Multidrug Resistant Cancer Cells Via Inhibiting Nrf2/Keap1 Signaling Pathway.

Multidrug-resistant (MDR) cancer cells maintain redox homeostasis to eliminate oxidative stress-mediated cell death. This study explores the effects of solasodine on regulating P-glycoprotein (P-gp) expression through the Nrf2/Keap1 signaling pathway and oxidative stress-induced sensitization of drug-resistant cancer cells to chemotherapeutics. Initially, the oxidative stress indicators such as intracellular ROS generation, the levels of 8-hydroxy-2-deoxyguanosine (8-OHdG) and gamma-H2AX (γ-H2AX) in the KBChR-8-5 drug-resistant cells were measured. Additionally, the protein expression levels of Nuclear factor erythroid 2-related factor 2 (Nrf-2), Kelch-like ECH-associated protein 1 (Keap1), and ATP Binding Cassette Subfamily B Member 1 (ABCB1)/P-gp were measured at various concentrations of solasodine (1, 5, & 10 µM) through immunofluorescence and western blot analysis. The antioxidant activities in the KBChR-8-5 cells were assessed using established protocols. In this investigation, the treatment with solasodine and doxorubicin combination showed a notable increase in intracellular ROS generation in KBChR-8-5 cells. Furthermore, this combination treatment led to enhanced nuclear condensation, elevated levels of 8-OHdG, and increased γ-H2AX foci formation in the KBChR-8-5 cells. Solasodine treatment effectively inhibited the nuclear translocation of Nrf2 and activation of the ABCB1 gene, consequently preventing overexpression of P-gp in KBChR-8-5 cells. Additionally, the combination therapy increased the lipid peroxidation levels while simultaneously reducing the activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and the levels of glutathione (GSH). These results demonstrated that solasodine disrupts redox balance, and overcomes drug resistance by downregulating P-gp via regulating Nrf2/Keap1 signaling pathway in MDR cancer cells.

The Impact of Dexamethasone and Prednisone on Apixaban and Rivaroxaban Exposure in COVID-19 Patients: A Physiologically Based Pharmacokinetic Modeling Study.

Dexamethasone (DEX) is currently the treatment of choice for patients with oxygen-dependent COVID-19. It has been observed, primarily in vitro, that dexamethasone induces the expression of CYP3A and the ABCB1 gene, which encodes P-glycoprotein (P-gp). This has raised concerns about potential interactions between DEX and substrates of CYP3A and P-gp, such as direct oral anticoagulants (DOAC). Currently, there is limited robust evidence to support a clinically significant interaction between DEX and DOAC. Using physiologically based pharmacokinetic modeling (PBPK), we investigated the impact of DEX administered in the context of SARS-CoV-2 infection on the pharmacokinetics of apixaban (APX) and rivaroxaban (RVX). After validating the induction effect of the DEX compound on two CYP3A4 substrates using the limited available studies, we optimized the compound in a COVID-19 patient population, where significantly higher DEX plasma concentrations were observed compared to healthy volunteers. Our PBPK-based PK simulations showed a 20% decrease in the AUC of APX and RVX in a worst-case scenario and when DEX was administered at 6 mg PO for 10 days. This finding confirms the limited clinical data currently available and supports the use of APX and RVX with DEX in COVID-19 patients at low-risk for thrombo-embolism. In addition, our results suggest that prednisone (PRED), when used at an equipotent dose, could serve as a viable alternative to DEX, given its less pronounced induction effect on APX and RVX. Further research is needed to validate these findings and to explore the clinical implications of using PRED in place of DEX in such scenarios.

Identification of novel ABCB4 variants and genotype-phenotype correlation in progressive familial intrahepatic cholestasis type 3

Progressive familial intrahepatic cholestasis type 3 (PFIC3) is a severe hepatic disorder characterized by cholestasis. Elucidating the genotype-phenotype correlations and expanding the mutational spectrum of the ABCB4 gene are crucial for enhancing diagnostic accuracy and therapeutic strategies.Clinical and genetic data from 2 original PFIC3 patients from our institution, along with 118 additional cases identified through a comprehensive literature review, were integrated for a comprehensive analysis. The study included statistical analysis of clinical information, genetic analysis, multi-species sequence alignment, protein structure modeling, and pathogenicity assessment. Machine learning techniques were applied to identify genotype-phenotype relationships. We identified three novel ABCB4 mutations: two missense mutations (c.904G > T and c.2493G > C) and one splicing mutation (c.1230 + 1G > A). Homozygous mutations were associated with significantly earlier disease onset compared to compound heterozygous mutations (p < 0.0001). Missense mutations were predominant (76.9%), with Exon 7 being the most frequently affected region. A random forest model indicated that Exon 10 had the highest feature importance score (9.9%). Liver transplantation remains the most effective treatment modality for PFIC3. This investigation broadens the known mutation spectrum of the ABCB4 gene and identifies key variant sites associated with clinical manifestations. These insights lay a foundation for early diagnosis, optimal treatment selection, and further research into PFIC3.

Multi-drug resistance-1 (MDR-1) gene expression in MCF-7 cells after treated with doxorubicin-deoxyelephantopin combination and prediction of inhibitory activity against Pgp receptors with in silico

Doxorubicin chemotherapy has been a strong focus in breast cancer research. Side effects, toxicity and resistance have been extensively studied. One proposed solution to these issues that its combination with deoxyelephantopin. Deoxyelephantopin is known to be toxic in many cancer cells but safe in normal cells. IC50 of each compound were determined by using a MTT assay, and the MDR-1 gene mRNA expression were determined by using qPCR method, while the interaction of doxorubicin in combination with deoxyelephantonin on Pgp receptor were predicted by using an in silico approach. The IC50 of deoxyelephantopin was found to be 11.2 µg/mL, while IC50 of doxorubicin was 448 nM IC50 values showed a deoxyelephantopin-doxorubicin combination was able to reduce MDR-1 expression by 19% compared to doxorubicin and ½ IC50 values indicated that the combination formula reduced the expression by 15% over doxorubicin alone. The affinity of doxorubicin and deoxyelephantopin is -12.16 kcal/mol and -9.51 kcal/mol, respectively, while the affinity of doxorubicin after combine with deoxyelephantopin decreases from -12,16 kcal/mol to -11,25 kcal/mol due to the release of one Leu 221 hydrogen bond. The combination of doxorubicin with deoxyelephantopin is able to reduce expression and suppress the function of the Pgp protein.

The combination of FLCWK with 5-FU inhibits colon cancer and multidrug resistance by activating PXR to suppress the IL-6/STAT3 pathway.

5-fluorouracil (5-FU) is a preferred chemotherapeutic agent for the treatment of colon cancer. Nonetheless, its clinical effectiveness is frequently hampered by suboptimal therapeutic outcomes and the emergence of drug resistance. Therefore, there exists a pressing demand for novel therapeutic agents to circumvent chemoresistance. The pregnane X receptor (PXR) exerts a pivotal regulatory influence on the proliferation, invasion, and chemoresistance mechanisms in colon cancer. Activation of PXR drives up the transcription of the multidrug resistance gene (MDR1), thus prompting the expression of P-glycoprotein (P-gp) responsible for conferring tumour resistance. This study scrutinized the potential of Fengliao Changweikang (FLCWK) in augmenting the efficacy of 5-FU in the management of colon cancer. To this end, we engineered colon cancer cells with varied levels of PXR expression via lentiviral transfection, subsequently validating the findings in nude mice. By means of MTT assays, flow cytometry apoptosis analysis, Western blotting and immunofluorescence, we probed into the prospective impacts of FLCWK and 5-FU on cellular viability and resistance. Our results revealed that while upregulation of PXR amplified the therapeutic benefits in colon cancer treatment, it concurrently heightened resistance levels. FLCWK demonstrated a capacity to reduce P-gp expression, with the combined administration of FLCWK and 5-FU effectively reversing resistance mechanisms. Furthermore, activation of PXR was found to impede the IL-6/STAT3 signalling pathway. In an effort to mimic the development of colon cancer, we established an azomethane oxide (AOM)/ dextran sodium sulfate (DSS) mouse model, showing that FLCWK bolstered the inhibitory effects of 5-FU, impeding the progression of colon cancer. In summation, our findings point towards the potential of FLCWK in the treatment of colon cancer, particularly in strengthening the therapeutic efficacy of 5-FU in the prevention and control of the disease.

Gilteritinib reverses ABCB1-mediated multidrug resistance: Preclinical in vitro and animal investigations

Multi-drug resistance (MDR) poses a significant challenge to cancer treatment. Targeting ATP-binding cassette subfamily B member 1 (ABCB1) is a viable strategy for overcoming MDR. This study examined the preclinical in vitro and animal studies that used gilteritinib, a FLT3 inhibitor that reverses ABCB1-mediated MDR. At nontoxic levels, gilteritinib significantly increased the susceptibility of cancer cells overexpressing ABCB1 to chemotherapeutic drugs. Furthermore, it impaired the development of drug-resistant cell colonies and 3D spheroids. Studies on the reversal mechanism have shown that gilteritinib can directly bind to the drug-binding site of ABCB1, inhibiting drug efflux activity. Consequently, the substrate’s drug cytotoxicity increases in MDR cells. Furthermore, gilteritinib increased ATPase activity while leaving ABCB1 expression and subcellular distribution unchanged and inhibited AKT or ERK activation. Docking analysis indicated that Gilteritinib could interact with the drug-binding site of the ABCB1 transporter. In vivo studies have shown that gilteritinib improves the antitumor efficacy of paclitaxel in nude mice without obvious toxic effects. In conclusion, our preclinical investigations show that gilteritinib has the potential to successfully overcome ABCB1-mediated MDR in a clinical environment when combined with substrate medicines.

Genomic characterization of a clonal emergent Salmonella Minnesota lineage in Brazil reveals the presence of a novel megaplasmid of resistance and virulence.

Salmonella Minnesota has emerged in Brazil as the predominant serovar in poultry and poultry products, along with Salmonella Heidelberg. To understand the emergence of Salmonella Minnesota over the last few years in Brazil, we performed a comparative analysis between 69 selected S. Minnesota genomes from Pathogen Detection database and 65 clonal emergent genomes isolated from Brazil. We demonstrate the presence of multidrug resistance genes against tetracycline [tet(A)], sulfonamide (sul2), and AmpC beta-lactamase (blaCMY-2) in emergent genomes, along with the carriage of a megaplasmid of resistance and virulence (~210 kb), designated pESM (plasmid for emergent Salmonella Minnesota). pESM is an IncC/A2 plasmid predicted to increase S. Minnesota environmental tolerance to mercury (mer operon) and provide resistance to tetracycline and ampicillin due to the presence of tet(A) and blaCMY-2, respectively. Moreover, pESM carries the yersiniabactin siderophore (high-pathogenicity island of Yersinia) related to the iron uptake. The temporal inference demonstrated that the most recent common ancestor dated from ~1978 and that the clonal emergent genomes carrying the pESM belong to a completely different lineage of S. Minnesota. Our results indicate that the presence of pESM likely contributes to the emergence of S. Minnesota and is precisely related to the successful spread of this particular clonal lineage in Brazil.IMPORTANCESalmonella Minnesota has emerged in Brazil as one of the leading serovars related to human and animal infection, presenting high virulence and antibiotic resistance to drugs classified as the highest priority for clinical treatment in humans. This study performed whole-genome sequencing, temporal analysis, and phylogenetics to understand the genetic insights related to the emergence of Salmonella Minnesota in Brazil. Long-read sequencing has led to the identification and characterization of a unique megaplasmid carrying virulence, antibiotic resistance, and heavy-metal tolerance genes, which may play a central role in S. Minnesota's successful emergence in Brazil and possibly worldwide. The potentially high transmissibility of this plasmid between clones and serovars represents a risk to public health since its acquisition may increase Salmonella's fitness, virulence, resistance, and persistence. Understanding the genetic aspects related to the emergence of serovars can help devise measures to mitigate the spread of hazardous multidrug-resistant strains.

Microbiome and Resistome Studies of the Lithuanian Baltic Sea Coast and the Curonian Lagoon Waters and Sediments.

the widespread use of antibiotics in human and veterinary medicine has contributed to the global challenge of antimicrobial resistance, posing significant environmental and public health risks. this study aimed to examine the microbiome and resistome dynamics across a salinity gradient, analyzing water and sediment samples from the Baltic Sea coast and the Curonian Lagoon between 2017 and 2023. the composition of the water and sediment bacterial community was determined by Full-Length Amplicon Metagenomics Sequencing, while ARG detection and quantification were performed using the SmartChipTM Real-Time PCR system. the observed differences in bacterial community composition between the Baltic Sea coast and the Curonian Lagoon were driven by variations in salinity and chlorophyll a (chl a) concentration. The genera associated with infectious potential were observed in higher abundances in sediment than in water samples. Over 300 genes encoding antibiotic resistance (ARGs), such as aminoglycosides, beta-lactams, and multidrug resistance genes, were identified. Of particular interest were those ARGs that have previously been detected in pathogens and those currently classified as a potential future threat. Furthermore, our findings reveal a higher abundance and a distinct profile of ARGs in sediment samples from the lagoon compared to water. these results suggest that transitional waters such as lagoons may serve as reservoirs for ARGs, and might be influenced by anthropogenic pressures and natural processes such as salinity fluctuation and nutrient cycling.