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Objectives: The human oral microbiome, a complex ecosystem linked to oral and systemic health, harbors a diverse array of microbial populations, including antimicrobial resistance genes (ARGs). As a critical component of the One Health approach to tackle antibiotic resistance, comprehending the oral resistome's composition and diversity is imperative. The objective of this study was to investigate the impact of chemical cell lysis treatment using MetaPolyzyme on the detectability of the oral microbiome, resistome, and DNA quality and quantity. Materials and Methods: Saliva samples were collected from five healthy individuals, and each of the samples was subjected to DNA extraction with and without the treatment with MetaPolyzyme. Through metagenomic sequencing, we analyzed, assessed, and compared the microbial composition, resistome, and DNA characteristics between both groups of extracted DNA. Results: Our study revealed that MetaPolyzyme treatment led to significant shifts in the detectability of microbial composition, favoring Gram‐positive bacteria, notably Streptococcus, over Gram‐negative counterparts. Moreover, the MetaPolyzyme treatment also resulted in a distinct change in ARG distribution. This shift was characterized by an elevated proportion of ARGs linked to fluoroquinolones and efflux pumps, coupled with a reduction in the prevalence of tetracycline and β‐lactam resistance genes when compared with the nontreated group. Alpha diversity analysis demonstrated altered species and ARG distribution without affecting overall diversity, while beta diversity analysis confirmed significant differences in the taxonomical composition and oral resistome between treated and nontreated groups. Conclusions: These findings underscore the critical role of cell lysis treatment in optimizing oral metagenomic studies and enhance our understanding of the oral resistome's dynamics in the context of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Background: Vancomycin-resistant enterococci (VRE) are important pathogens categorized as high-priority bacteria in the Global Priority List of Antibiotic-Resistant Bacteria to Guide Research, Discovery, and Development of New Antibiotics published by the World Health Organization. The aim of this study was to determine the risk factors, resistance, virulence, mobilomes associated with multidrug-resistant and clonal lineages of Enterococcus faecium and faecalis circulating among hospitalized patients following the health system in South Africa, using whole genome sequencing (WGS). Methods: A cross-sectional study was conducted during a two-month periods among hospitalized patients in 2017. Rectal swabs were collected from patients admitted to medical and surgical wards in an urban tertiary hospital, and a rural district hospital in uMgungundlovu district, South Africa. Enterococci were screened for vancomycin resistance on bile esculin azide agar supplemented with 6 mg/L of vancomycin and confirmation of VRE was done using ROSCO kits. Conventional and real-time PCR methods were used to ascertain the presence of VanA, VanB, VanC-2/3 and VanC-1 genes. All six multidrug-resistant Enterococcus faecalis and faecium selected were identified using multiplexed paired-end libraries (2 × 300 bp) with the Nextera XT DNA sample preparation kit (Illumina, San Diego, CA, USA) and genome sequencing was done using Illumina MiSeq instrument with 100× coverage at the National Institute of Communicable Diseases Sequencing Core Facility, South Africa. Antibiotic resistance genes, virulence factors, plasmids, integrons and CRISPR were characterized using RAST, ResFinder, VirulenceFinder, PlasmidFinder, PHAST and ISFinder respectively. Results: Sequencing analysis revealed that these strains harbouring numerous resistance genes to glycopeptides (vanC[100%], vex3[100%], vex2[83,33%] and vanG[16,66%]), macrolides, lincosamides, sterptogramine B (ermB[33,32%], Isa[16,66%], emeA[16,66%]) and tetracyclines (tetM[33,32%]) in both district and tertiary hospitals. Multidrug efflux pumps including MATE, MFS and pmrA conferring resistance to several classes of antibiotics were also identified. The main transposable elements observed were in the Tn3 family, specifically Tn1546. Four single sequence types (STs) were identified among E. faecium in the district hospital, namely ST822, ST636, ST97 along with a novel ST assigned ST1386, while one lineage, ST29 was detected in the tertiary hospital. Conclusion: The study reveals the genetic diversity and high pathogenicity of multidrug-resistant Enterococcus faecalis and faecium circulating among hospitalized patients. It underlines the necessity to implement routine screening of admitted patients coupled with infection control procedures, antimicrobial stewardship and awareness should be strengthened to prevent and/or contain the carriage and spread of multidrug resistant E. faecium and E. faecalis in hospitals and communities in South Africa. [ABSTRACT FROM AUTHOR]

Background and aim: Sepsis-induced acute lung injury (ALI) is a complex and life-threatening condition lacking specific and efficient clinical treatments. Extracellular histones, identified as a novel type of damage-associated molecular patterns, have been implicated in the inflammatory process of ALI. However, further elucidation is needed regarding the precise mechanism through which extracellular histones induce inflammation. The aim of this study was to investigate whether extracellular histones can activate NLRP3 inflammasome-mediated inflammation in alveolar macrophages (AMs) by affecting TWIK2-dependent potassium efflux. Methods and results: We conducted experiments using cecal ligation and puncture (CLP) C57BL/6 mice and extracellular histone-stimulated LPS-primed MH-S cells. The results demonstrated a significant increase in the levels of extracellular histones in the plasma and bronchoalveolar lavage fluid (BALF) of CLP mice. Furthermore, neutralizing extracellular histone mitigated lung injury and inflammation in CLP-induced ALI mice. In vitro studies confirmed that extracellular histones upregulated the expression of NLRP3 inflammasome activation-related proteins in MH-S cells, and this effect was dependent on increased potassium efflux mediated by the TWIK2 channel on the plasma membrane. Moreover, extracellular histones directly triggered a substantial influx of calcium, leading to increased Rab11 activity and facilitating the trafficking and location of TWIK2 to the plasma membrane. Conclusion: These findings underscore the critical role of extracellular histone-induced upregulation of TWIK2 expression on the plasma membrane of alveolar macrophages (AMs). This upregulation leads to potassium efflux and subsequent activation of the NLRP3 inflammasome, ultimately exacerbating lung inflammation and injury during sepsis. [ABSTRACT FROM AUTHOR]

Acetic acid bacteria (AAB) are major contributors to the production of fermented vinegar, offering various cultural, culinary, and health benefits. Although the residual unpasteurized AAB after vinegar production are not pathogens, these are necessary and require safety evaluations, including antibiotic resistance, before use as a starter. In this research, we investigated the antibiotic resistance profiles of 26 AAB strains, including various species of Komagataeibacter and Acetobacter, against 10 different antibiotics using the E-test method. All strains exhibited resistance to aztreonam and clindamycin. Komagataeibacter species demonstrated a 50% resistance rate to ciprofloxacin, analogous to Acetobacter species, but showed twice the resistance rates to chloramphenicol and erythromycin. Genomic analysis of K. saccharivorans CV1 identified intrinsic resistance mechanisms, such as multidrug efflux pumps, thereby enhancing our understanding of antibiotic resistance in acetic acid-producing bacteria. These findings enhance understanding of antibiotic resistance in AAB for food safety and new antimicrobial strategies, suggesting the need for standardized testing methods and molecular genetic study. [ABSTRACT FROM AUTHOR]

Nowadays, infectious diseases of bacterial and viral origins represent a serious medical problem worldwide. In fact, the development of antibiotic resistance is responsible for the emergence of bacterial strains that are refractory even to new classes of antibiotics. Furthermore, the recent COVID-19 pandemic suggests that new viruses can emerge and spread all over the world. The increase in infectious diseases depends on multiple factors, including malnutrition, massive migration of population from developing to industrialized areas, and alteration of the human microbiota. Alternative treatments to conventional antibiotics and antiviral drugs have intensively been explored. In this regard, plants and marine organisms represent an immense source of products, such as polyphenols, alkaloids, lanthipeptides, and terpenoids, which possess antibacterial and antiviral activities. Their main mechanisms of action involve modifications of bacterial cell membranes, with the formation of pores, the release of cellular content, and the inhibition of bacterial adherence to host cells, as well as of the efflux pump. Natural antivirals can interfere with viral replication and spreading, protecting the host with the enhanced production of interferon. Of note, these antivirals are not free of side effects, and their administration to humans needs more research in terms of safety. Preclinical research with natural antibacterial and antiviral compounds confirms their effects against bacteria and viruses, but there are still only a few clinical trials. Therefore, their full exploitation and more intensive clinical studies represent the next steps to be pursued in this area of medicine. [ABSTRACT FROM AUTHOR]

Background: Clopidogrel has been the primary choice of antiplatelet in ischemic stroke that inhibits adenosine diphosphate (ADP)-induced platelet aggregation. P-glycoprotein (P-gp) multidrug resistance-1 (MDR1) is a transmembrane efflux transporter in intestinal cells that plays a significant role in clopidogrel absorption, therefore may affect platelet aggregation. P-gp is encoded by the ABCB1 gene. This study aims to evaluate the effect of ABCB1 polymorphism on clopidogrel response variability in ischemic stroke patients and its genotype frequency. Methods: A cross-sectional study was conducted in ischemic stroke patients who received clopidogrel between 2020 and 2023 in RSUI/RSCM. All subjects were assessed for ABCB1 polymorphisms C3435T and C1236T. Platelet aggregation were measured using VerifyNow PRU. Clopidogrel response variability was classified into unresponsive (> 208 PRU), responsive (95–208 PRU), and bleeding risk (< 95 PRU). Results: 124 subjects enrolled in this study, with 12,9% of subjects classified as non-responsive/resistant, 49,5% as responsive, and 41,9% as bleeding risk. ABCB1 C1236T homozygote wildtype (CC) was associated with 3,76 times higher bleeding risk than other variants (p = 0,008; 95%CI 1,41 − 10,07). Genotype frequency of ABCB1 C3435T homozygote wildtype, heterozygote, and homozygote variants were 35,9%, 43,5% and 16,9%, respectively; while the genotype frequency of ABCB1 C1236T were 17,8%, 39,5%, and 42,7%, respectively. Conclusion: ABCB1 C1236T homozygote wildtype was associated with 3,76 times higher bleeding risk than other variants. The most common genotype frequency of ABCB1 C1236T was homozygote variant; while for ABCB1 C3435T was heterozygote. [ABSTRACT FROM AUTHOR]

Candida albicans, as a notorious fungal pathogen, is associated with high morbidity and mortality worldwide due to its ability to form biofilms and persisters that can withstand currently available antifungals. Direct current (DC) has demonstrated a promising antimicrobial effect and synergistic effect with antimicrobials against various infections. Here, we first found DC exerted a killing effect on C. albicans planktonic and biofilm cells. Moreover, DC showed a synergistic effect with fluconazole (FLC) and amphotericin B (AMB). Notably, near-to-complete eradication of AMB-tolerant C. albicans biofilm persisters was achieved upon DC treatment. Next, the mechanism of action of DC was explored through mapping the genes and proteomic profiles of DC-treated C. albicans. The multi-omics analysis, quantitative real-time PCR and assay of reactive oxygen species (ROS) demonstrated DC exerted an antifungal effect on C. albicans by increasing cellular oxidative stress. As revealed by multiple analyses (e.g., protein assay based on absorbance at 280 nm and rhodamine 6G assay), DC was able to enhance membrane permeability, inhibit drug efflux and increase cellular FLC/AMB concentration of C. albicans, thereby mediating its synergism with the antifungals. Furthermore, DC inhibited superoxide dismutase 2 (SOD2) expression and manganese-containing SOD (Mn SOD) activity, leading to ROS production and enhanced killing of C. albicans biofilm persisters. The current findings demonstrate that the adjunctive use of DC in combination with antifungals is a promising strategy for effective control of C. albicans infections and management of antifungal resistance/tolerance in Candida biofilms. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the occurrence of plasmid mediated quinolone resistance (PMQR) determinants in Campylobacter coli isolates collected from broilers, laying hens and poultry farm environments. One hundred and thirty-nine C. coli isolates were isolated from broilers (n = 41), laying hens (n = 53), eggs (n = 4) and the environment (n = 41) of 23 poultry farms located in northeastern of Tunisia. Antimicrobial susceptibility testing was performed on all isolates according to the recommendation of the European Committee on Antimicrobial Susceptibility Testing guidelines. The detection of PMQR genes: qnrA, qnrB, qnrC, qnrD, qnrS, qepA, and aac(6)-Ib gene was performed using polymerase chain reaction (PCR) and specific primers. aac(6′)-Ib amplicons were further analyzed by digestion with BtsCI to identify the aac(6′)-Ib-cr variant. Mutations in GyrA and the occurrence of RE-CmeABC efflux pump were determined by mismatch amplification mutation assay (MAMA) PCR and PCR, respectively. In addition, eleven isolates were selected to determine their clonal lineage by MLST. The 139 C. coli isolates were resistant to ciprofloxacin, and 86 (61.8%) were resistant to nalidixic acid. High rates of resistance were also observed toward erythromycin (100%), azithromycin (96.4%), tetracycline (100%), chloramphenicol (98.56%), ampicillin (66.1%), amoxicillin-clavulanic acid (55.39%), and kanamycin (57.55%). However, moderate resistance rates were observed for gentamicin (9.35%) and streptomycin (22.3%). All quinolone-resistant isolates harbored the Thr-86-Ile amino acid substitution in GyrA, and the RE-CmeABC efflux pump was detected in 40.28% of isolates. Interestingly, the qnrB, qnrS, qepA, and aac(6′)-Ib-cr were detected in 57.7%, 61.15%, 21.58%, and 10% of isolates, respectively. The eleven isolates studied by MLST belonged to a new sequence type ST13450. This study described for the first time the occurrence of PMQR genes in C. coli isolates in Tunisia and globally. [ABSTRACT FROM AUTHOR]

BACKGROUND. Preclinical studies suggest that cholesterol accumulation leads to insulin resistance. We previously reported that alterations in a monocyte cholesterol metabolism transcriptional network (CMTN) -- suggestive of cellular cholesterol accumulation -- were cross-sectionally associated with obesity and type 2 diabetes (T2D). Here, we sought to determine whether the CMTN alterations independently predict incident prediabetes/T2D risk, and correlate with cellular cholesterol accumulation. METHODS. Monocyte mRNA expression of 11 CMTN genes was quantified among 934 Multi-Ethnic Study of Atherosclerosis (MESA) participants free of prediabetes/T2D; cellular cholesterol was measured in a subset of 24 monocyte samples. RESULTS. During a median 6-year follow-up, lower expression of 3 highly correlated LXR target genes -- ABCG1 and ABCA1 (cholesterol efflux) and MYLIP (cholesterol uptake suppression) -- and not other CMTN genes, was significantly associated with higher risk of incident prediabetes/T2D. Lower expression of the LXR target genes correlated with higher cellular cholesterol levels (e.g., 47% of variance in cellular total cholesterol explained by ABCG1 expression). Further, adding the LXR target genes to overweight/obesity and other known predictors significantly improved prediction of incident prediabetes/T2D. CONCLUSION. These data suggest that the aberrant LXR/ABCG1-ABCA1-MYLIP pathway (LAAMP) is a major T2D risk factor and support a potential role for aberrant LAAMP and cellular cholesterol accumulation in diabetogenesis. FUNDING. The MESA Epigenomics and Transcriptomics Studies were funded by NIH grants 1R01HL101250, 1RF1AG054474, R01HL126477, R01DK101921, and R01HL135009. This work was supported by funding from NIDDK R01DK103531 and NHLBI R01HL119962. [ABSTRACT FROM AUTHOR]

The global fight against Tuberculosis (TB) persists; grappling with approximately 10.6 million new cases in 2021, as documented in the 2022 WHO Global TB Report.1 Of concern is the escalating incidence of multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB), which saw an estimated 450,000 new cases in the same year. Today's major problem in the treatment of Mycobacterium TB is drug resistance brought on by anti-TB therapy. The degree of resistance led to variations and other effects that eventually ended in death and health risks. The advent of certain drug-resistant strains of TB that are resistant to several treatments, prolonged drugs and all drugs is going to bring a major and catastrophic comeback to the disease. Current advancements in TB treatment help to reduce anti-tubercular medication resistance. Due to Mycobacterium tuberculosis's extraordinary flexibility, drug resistance in tuberculosis is a complicated phenomenon. Via genetic mutations, efflux pumps and other processes, these bacteria may become resistant to anti-TB medications. Hence, against drug-resistant bacteria, conventional TB treatment regimens-which usually include a mix of antibiotics-may stop working. The worldwide account will lose about 200,000 due to medication resistance fatalities in a single year. The development of vaccines against tuberculosis is a promising topic, but progress has been hampered by a lack of funding, organization and understanding of immunological responses. A Tubercular Vaccine Accelerator Council will combine resources and expertise to tackle these issues and accelerate development. Accomplish the WHO's goal of TB eradication by 2030. [ABSTRACT FROM AUTHOR]

Background: Dysregulation of cholesterol metabolism is associated with the metastasis of triple-negative breast cancer (TNBC). Apolipoprotein A1 (ApoA1) is widely recognized for its pivotal role in regulating cholesterol efflux and maintaining cellular cholesterol homeostasis. However, further exploration is needed to determine whether it inhibits TNBC metastasis by affecting cholesterol metabolism. Additionally, it is necessary to investigate whether ApoA1-based oncolytic virus therapy can be used to treat TNBC. Methods: In vitro experiments and mouse breast cancer models were utilized to evaluate the molecular mechanism of ApoA1 in regulating cholesterol efflux and inhibiting breast cancer progression and metastasis. The gene encoding ApoA1 was inserted into the adenovirus genome to construct a recombinant adenovirus (ADV-ApoA1). Subsequently, the efficacy of ADV-ApoA1 in inhibiting the growth and metastasis of TNBC was evaluated in several mouse models, including orthotopic breast cancer, spontaneous breast cancer, and human xenografts. In addition, a comprehensive safety assessment of Syrian hamsters and rhesus monkeys injected with oncolytic adenovirus was conducted. Results: This study found that dysregulation of cholesterol homeostasis is critical for the progression and metastasis of TNBC. In a mouse orthotopic model of TNBC, a high-cholesterol diet promoted lung and liver metastasis, which was associated with keratin 14 (KRT14), a protein responsible for TNBC metastasis. Furthermore, studies have shown that ApoA1, a cholesterol reverse transporter, inhibits TNBC metastasis by regulating the cholesterol/IKBKB/FOXO3a/KRT14 axis. Moreover, ADV-ApoA1 was found to promote cholesterol efflux, inhibit tumor growth, reduce lung metastasis, and prolonged the survival of mice with TNBC. Importantly, high doses of ADV-ApoA1 administered intravenously and subcutaneously were well tolerated in rhesus monkeys and Syrian hamsters. Conclusions: This study provides a promising oncolytic virus treatment strategy for TNBC based on targeting dysregulated cholesterol metabolism. It also establishes a basis for subsequent clinical trials of ADV-ApoA1 in the treatment of TNBC. [ABSTRACT FROM AUTHOR]

The glymphatic system plays a key role in the clearance of waste from the parenchyma, and its dysfunction has been associated with the pathogenesis of Alzheimer's disease (AD). However, questions remain regarding its complete mechanisms. Here, we report that efflux of cerebrospinal fluid (CSF)/interstitial fluid (ISF) solutes occurs through a triphasic process that cannot be explained by the current model, but rather hints at the possibility of other, previously undiscovered routes from paravenous spaces to the blood. Using real‐time, in vivo observation of efflux, a novel drainage pathway was discovered, in which CSF molecules enter the bloodstream directly through dynamically assembled, trumpet‐shaped pores (basolateral ϕ<8 μm; apical ϕ < 2 μm) on the walls of brain venules. As Zn2+ could facilitate the brain clearance of macromolecular ISF solutes, Zn2+‐induced reconstruction of the tight junctions (TJs) in vascular endothelial cells may participate in pore formation. Thus, an updated model for glymphatic clearance of brain metabolites and potential regulation is postulated. In addition, deficient clearance of Aβ through these asymmetric venule pores was observed in AD model mice, supporting the notion that impaired brain drainage function contributes to Aβ accumulation and pathogenic dilation of the perivascular space in AD. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is an opportunistic pathogen that produces respiratory infections in immunosuppressed and cystic fibrosis patients. The therapeutic options to treat S. maltophilia infections are limited since it exhibits resistance to a wide variety of antibiotics such as β-lactams, aminoglycosides, tetracyclines, cephalosporins, macrolides, fluoroquinolones, or carbapenems. The antibiotic combination trimethoprim/sulfamethoxazole (SXT) is the treatment of choice to combat infections caused by S. maltophilia, while ceftazidime, ciprofloxacin, or tobramycin are used in most SXT-resistant infections. In the current study, experimental evolution and whole-genome sequencing (WGS) were used to examine the evolutionary trajectories of S. maltophilia towards resistance against tobramycin, ciprofloxacin, and SXT. The genetic changes underlying antibiotic resistance, as well as the evolutionary trajectories toward that resistance, were determined. Our results determine that genomic changes in the efflux pump regulatory genes smeT and soxR are essential to confer resistance to ciprofloxacin, and the mutation in the rplA gene is significant in the resistance to tobramycin. We identified mutations in folP and the efflux pump regulator smeRV as the basis of SXT resistance. Detailed and reliable knowledge of ciprofloxacin, tobramycin, and SXT resistance is essential for safe and effective use in clinical settings. Herein, we were able to prove once again the extraordinary ability that S. maltophilia has to acquire resistance and the importance of looking for alternatives to combat this resistance. [ABSTRACT FROM AUTHOR]

Objectives: Antibiotic treatment is extremely stressful for bacteria and has profound effects on their viability. Such administration induces physiological changes in bacterial cells, with considerable impact on their genome structure that induces mutations throughout the entire genome. This study investigated drug resistance profiles and structural changes in the entire genome of uropathogenic Escherichia coli (UPEC) strains isolated from six adapted clones that had evolved under laboratory conditions. Methods: Eight UPEC strains, including two parental strains and six adapted clones, with different fluoroquinolone resistance levels originally isolated from two patients were used. The minimum inhibitory concentration (MIC) of 28 different antibiotics including levofloxacin was determined for each of the eight strains. In addition, the effects of mutations acquired with increased drug resistance in the levofloxacin‐resistant strains on expression of genes implicated to be involved in drug resistance were examined. Results: Of the eight UPEC strains used to test the MIC of 28 different antibiotics, two highly fluoroquinolone‐resistant strains showed increased MIC in association with many of the antibiotics. As drug resistance increased, some genes acquired mutations, including the transcriptional regulator acrR and DNA‐binding transcriptional repressor marR. Two strain groups with genetically different backgrounds (GUC9 and GFCS1) commonly acquired mutations in acrR and marR. Notably, acquired mutations related to efflux pump upregulation also contributed to increases in MIC for various antibiotics other than fluoroquinolone. Conclusions: The present results obtained using strains with artificially acquired drug resistance clarify the underlying mechanism of resistance to fluoroquinolones and other types of antibiotics. [ABSTRACT FROM AUTHOR]

The management of metastatic cancer is complicated by chemotherapy resistance. This manuscript provides a comprehensive academic review of strategies to overcome chemotherapy resistance in metastatic cancer. The manuscript presents background information on chemotherapy resistance in metastatic cancer cells, highlighting its clinical significance and the current challenges associated with using chemotherapy to treat metastatic cancer. The manuscript delves into the molecular mechanisms underlying chemotherapy resistance in subsequent sections. It discusses the genetic alterations, mutations, and epigenetic modifications that contribute to the development of resistance. Additionally, the role of altered drug metabolism and efflux mechanisms, as well as the activation of survival pathways and evasion of cell death, are explored in detail. The strategies to overcome chemotherapy resistance are thoroughly examined, covering various approaches that have shown promise. These include combination therapy approaches, targeted therapies, immunotherapeutic strategies, and the repurposing of existing drugs. Each strategy is discussed in terms of its rationale and potential effectiveness. Strategies for early detection and monitoring of chemotherapy drug resistance, rational drug design vis-a-vis personalized medicine approaches, the role of predictive biomarkers in guiding treatment decisions, and the importance of lifestyle modifications and supportive therapies in improving treatment outcomes are discussed. Lastly, the manuscript outlines the clinical implications of the discussed strategies. It provides insights into ongoing clinical trials and emerging therapies that address chemotherapy resistance in metastatic cancer cells. The manuscript also explores the challenges and opportunities in translating laboratory findings into clinical practice and identifies potential future directions and novel therapeutic avenues. This comprehensive review provides a detailed analysis of strategies to overcome chemotherapy resistance in metastatic cancer. It emphasizes the importance of understanding the molecular mechanisms underlying resistance and presents a range of approaches for addressing this critical issue in treating metastatic cancer. [ABSTRACT FROM AUTHOR]

While it is recognized that non-alcoholic fatty liver disease (NAFLD) is associated with cardiovascular disease (CVD), how NAFLD affects the development and progression of CVD remains unclear and debatable. Hence, we aimed to determine the role of steatotic hepatocyte-derived small extracellular vesicles (sEVs) in foam cell formation and atherosclerosis progression. sEVs from steatotic hepatocytes were isolated and characterized. MicroRNA (miRNA) deep sequencing was utilized to identify functional miRNA in sEVs. Lastly, we conducted a cross-sectional study on patients with NAFLD to validate these findings. Treatment of sEVs from steatotic hepatocytes promoted macrophage-derived foam cell formation and atherosclerosis progression via inhibition of ABCA1-mediated cholesterol efflux. Macrophage-specific deletion of Abca1 in ApoE -/- mice abolished the role of steatotic hepatocyte-derived sEVs in atherosclerosis progression. In addition, hepatocyte-specific deletion of Rab27a , which is the key GTPase regulating sEV release, significantly ameliorated high-fat, high-cholesterol diet-induced atherosclerosis progression in ApoE -/- mice. The miRNA deep sequencing results showed that miR-30a-3p was enriched in sEVs from steatotic hepatocytes. miR-30a-3p directly targeted the 3' untranslated region of ABCA1 to inhibit ABCA1 expression and cholesterol efflux. Treatment with antagomiR-30a-3p significantly attenuated atherosclerosis progression in high-fat, high-cholesterol diet-fed ApoE -/- mice. Moreover, serum sEVs from patients with NAFLD and sEV-miR-30a-3p expression were associated with decreased cholesterol efflux levels in foam cells. Steatotic hepatocyte-derived sEVs promote foam cell formation and facilitate atherogenesis via the miR-30a-3p/ABCA1 axis. Reducing sEV secretion by steatotic hepatocytes or targeting miR-30a-3p may be potential therapeutic approaches to slow the progression of NAFLD-driven atherosclerosis. The presence of hepatic steatosis is strongly correlated with the risk of cardiovascular disease and cardiovascular events, yet the molecular mechanisms linking steatosis to progression of atherosclerosis are unclear. Herein, we identified small extracellular vesicles from steatotic hepatocytes as a trigger that accelerated the progression of atherosclerosis. Steatotic hepatocyte-derived small extracellular vesicles promoted foam cell formation via the miR-30a-3p/ABCA1 axis. Our findings not only provide mechanistic insight into non-alcoholic fatty liver disease-driven atherosclerosis but also provide potential therapeutic targets for patients with atherosclerosis. [Display omitted] • Extracellular vesicles from steatotic hepatocytes promote foam cell formation in atherosclerosis. • Steatotic hepatocyte-derived extracellular vesicles inhibit ABCA1-mediated cholesterol efflux via miR-30a-3p. • Inhibition of extracellular vesicle release from hepatocytes ameliorates atherosclerosis progression in ApoE -/- mice. • Treatment of antagomiR-30a-3p attenuates high-fat, high-cholesterol diet-induced atherosclerosis progression in ApoE -/- mice. [ABSTRACT FROM AUTHOR]

Mycobacterium (M.) abscessus, a highly pathogenic non-tuberculous mycobacterium, is responsible for several clinical manifestations. A very frequent occurrence is proven in patient with various lung diseases. Furthermore, it can result in complications such as skin and soft tissue diseases, central nervous system infections, bacteremia, eye infections, and others. M. abscessus is a clinical contraindication in cystic fibrosis patients awaiting a lung transplant, as it can exacerbate disease progression. Its pathogenicity and the emergence of resistance are influenced by factors including the composition of the cell envelope, rough and smooth M. abscessus morphotypes, efflux pumps, antibiotic-modifying/inactivating enzymes, and genetic polymorphisms in target genes. Management of the infection requires multicomponent therapy due to the high level of resistance. The following antibiotics are recommended according to the guidelines from the year 2017: amikacin, tigecycline, and imipenem with a macrolide. In order to properly manage patients with M. abscessus infection, correct identification of the subspecies as well as determination of resistance is essential. To achieve this goal, molecular-genetic techniques, such as whole-genome sequencing, are becoming increasingly favored in modern clinical practice. In this review, we provide up-to-date information on the issue of infections caused by non-tuberculous M. abscessus. We focus on its characteristics, possible infectious diseases, cystic fibrosis, and resistance, as well as the benefits of whole-genome sequencing. [ABSTRACT FROM AUTHOR]

Objective: Sepsis may often result in acute lung injury (ALI), with a high mortality and morbidity. Available evidence indicates that activation of NLRP3 inflammasome to induce macrophage inflammation plays a crucial role in the inflammation progression of ALI and lidocaine can attenuate inflammatory responses. We hypothesized that lidocaine may attenuate inflammatory response and sepsis-induced ALI by inhibiting potassium efflux-dependent NLRP3 activation. Methods: C57BL/6N mice were randomized and divided into six groups (n = 6) receiving different treatments. Lung vascular permeability and histological changes in the lungs were evaluated by Evans blue dye, bronchoalveolar lavage analysis and hematoxylin and eosin staining. J774A.1 macrophages were divided into 12 groups receiving different treatments. The expression of both NLRP3 inflammasome activation-related protein and P2X7 in the macrophages was measured by immunofluorescence staining and Western blots. The whole cell currents were determined by a voltage-patch clamp technique. Results: Challenge with LPS led to ALI in mice with an increased lung injury score (0.54 ± 0.09), which was significantly attenuated by lidocaine pretreatment (0.20 ± 0.08, P < 0.0001). Lidocaine pretreatment significantly decreased the NLRP3 activation and IL-1β release in the macrophages. Furthermore, lidocaine pretreatment down-regulated the expression of P2X7 receptors, inhibited LPS- and ATP-induced sodium (Na+) inward flow, and maintained the intracellular K+ level in the macrophages. In addition, activation of Na+ influx did not eliminate anti-inflammatory effect of lidocaine. The activation of NLRP3 could be suppressed by extracellular K+ level in a dose-dependent model. However, lidocaine pretreatment eliminated NLRP3 activation and IL-1β release induced by K+ efflux, and decreased outward K+ current and extracellular K+ level in the macrophages challenged by LPS/ATP. Conclusions: Lidocaine pretreatment can attenuate the sepsis-induced ALI by an anti-inflammatory mechanism of inhibiting K+ efflux-dependent NLRP3 activation. [ABSTRACT FROM AUTHOR]

Immune cells sense the microenvironment to fine-tune their inflammatory responses. Patients with cryopyrin-associated periodic syndrome (CAPS), caused by mutations in the NLRP3 gene, develop autoinflammation triggered by nonantigenic cues such as from the environment. However, the underlying mechanisms are poorly understood. Here, we uncover that KCNN4, a calcium-activated potassium channel, links PIEZO-mediated mechanotransduction to NLRP3 inflammasome activation. Yoda1, a PIEZO1 agonist, lowered the threshold for NLRP3 inflammasome activation. PIEZO-mediated sensing of stiffness and shear stress increased NLRP3-dependent inflammation. Myeloid-specific deletion of PIEZO1/2 protected mice from gouty arthritis. Mechanistically, activation of PIEZO1 triggers calcium influx, which activates KCNN4 to evoke potassium efflux and promotes NLRP3 inflammasome activation. Activation of PIEZO signaling was sufficient to activate the inflammasome in cells expressing CAPS-causing NLRP3 mutants via KCNN4. Last, pharmacological inhibition of KCNN4 alleviated autoinflammation in cells of patients with CAPS and in mice bearing a CAPS mutation. Thus, PIEZO-dependent mechanical inputs boost inflammation in NLRP3-dependent diseases, including CAPS. Editor's summary: Inflammasomes are cytosolic multiprotein complexes that can rapidly assemble and activate proinflammatory signaling in response to diverse stimuli, but whether mechanical cues affect inflammasome activity is unknown. Using macrophages treated with the PIEZO1 agonist Yoda1 and exposed to distinct mechanical environments, Ran et al. demonstrated that PIEZO-mediated mechanotransduction enhances NLRP3 inflammasome activation. Potassium efflux through the calcium-activated channel KCNN4, identified using a genome-wide CRISPR knockout screen, was required for PIEZO1-mediated enhancement of NLRP3 inflammasome activation. Pharmacological inhibition of KCNN4 in mice and human cells bearing cryopyrin-associated periodic syndrome (CAPS)–causing NLRP3 mutations reduced autoinflammation. These findings identify a link between PIEZO-mediated mechanotransduction and NLRP3-related inflammatory diseases. —Claire Olingy [ABSTRACT FROM AUTHOR]

Nearly 50 ATP-binding cassette (ABC) transporters are encoded by mammalian genomes. These transporters are characterized by conserved nucleotidebinding and hydrolysis (i.e., ATPase) domains, and power directional transport of diverse substrate classes – ions, small molecule metabolites, xenobiotics, hydrophobic drugs, and even polypeptides – into or out of cells or subcellular organelles. Although immunological functions of ABC transporters are only beginning to be unraveled, emerging literature suggests these proteins have under-appreciated roles in the development and function of T lymphocytes, including many of the key effector, memory and regulatory subsets that arise during responses to infection, inflammation or cancers. One transporter in particular, MDR1 (Multidrug resistance-1; encoded by the ABCB1 locus in humans), has taken center stage as a novel player in immune regulation. Although MDR1 remains widely viewed as a simple drug efflux pump in tumor cells, recent evidence suggests that this transporter fills key endogenous roles in enforcing metabolic fitness of activated CD4 and CD8 T cells. Here, we summarize current understanding of the physiological functions of ABC transporters in immune regulation, with a focus on the anti-oxidant functions of MDR1 that may shape both the magnitude and repertoires of antigen-specific effector and memory T cell compartments. While much remains to be learned about the functions of ABC transporters in immunobiology, it is already clear that they represent fertile new ground, both for the definition of novel immunometabolic pathways, and for the discovery of new drug targets that could be leveraged to optimize immune responses to vaccines and cancer immunotherapies. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae (S. pneumoniae) is a bacterial species often associated with the occurrence of community-acquired pneumonia (CAP). CAP refers to a specific kind of pneumonia that occurs in individuals who acquire the infection outside of a healthcare setting. It represents the leading cause of both death and morbidity on a global scale. Moreover, the declaration of S. pneumoniae as one of the 12 leading pathogens was made by the World Health Organization (WHO) in 2017. Antibiotics like β-lactams, macrolides, and fluoroquinolones are the primary classes of antimicrobial medicines used for the treatment of S. pneumoniae infections. Nevertheless, the efficacy of these antibiotics is diminishing as a result of the establishment of resistance in S. pneumoniae against these antimicrobial agents. In 2019, the WHO declared that antibiotic resistance was among the top 10 hazards to worldwide health. It is believed that penicillin-binding protein genetic alteration causes β-lactam antibiotic resistance. Ribosomal target site alterations and active efflux pumps cause macrolide resistance. Numerous factors, including the accumulation of mutations, enhanced efflux mechanisms, and plasmid gene acquisition, cause fluoroquinolone resistance. Furthermore, despite the advancements in pneumococcal vaccinations and artificial intelligence (AI), it is not feasible for individuals to rely on them indefinitely. The ongoing development of AI for combating antimicrobial resistance necessitates more research and development efforts. A few strategies can be performed to curb this resistance issue, including providing educational initiatives and guidelines, conducting surveillance, and establishing new antibiotics targeting another part of the bacteria. Hence, understanding the resistance mechanism of S. pneumoniae may aid researchers in developing a more efficacious antibiotic in future endeavors. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is a non-cutaneous malignancy in males with wide variation in incidence rates across the globe. It is the second most reported cause of cancer death. Its etiology may have been linked to genetic polymorphisms, which are not only dominating cause of malignancy casualties but also exerts significant effects on pharmacotherapy outcomes. Although many therapeutic options are available, but suitable candidates identified by useful biomarkers can exhibit maximum therapeutic efficacy. The single-nucleotide polymorphisms (SNPs) reported in androgen receptor signaling genes influence the effectiveness of androgen receptor pathway inhibitors and androgen deprivation therapy. Furthermore, SNPs located in genes involved in transport, drug metabolism, and efflux pumps also influence the efficacy of pharmacotherapy. Hence, SNPs biomarkers provide the basis for individualized pharmacotherapy. The pharmacotherapeutic options for PCa include hormonal therapy, chemotherapy (Docetaxel, Mitoxantrone, Cabazitaxel, and Estramustine, etc.), and radiotherapy. Here, we overview the impact of SNPs reported in various genes on the pharmacotherapy for PCa and evaluate current genetic biomarkers with an emphasis on early diagnosis and individualized treatment strategy in PCa. [ABSTRACT FROM AUTHOR]

Objective: Atherosclerosis is a chronic inflammatory process induced by the influx and entrapment of excess lipoproteins into the intima media of arteries. Previously, our lab demonstrated that systemic PTP1B inhibition protects against atherosclerosis in preclinical LDLR−/− models. Similarly, it was shown that myeloid-specific PTP1B ablation decreases plaque formation and ameliorates dyslipidaemia in the ApoE−/− model of atherosclerosis. We hypothesized that the relevant improvements in dyslipidaemia following modification of PTP1B activation may either result from changes in hepatic cholesterol biosynthesis and/or increased uptake and degradation by liver-resident macrophages. We examined this in animal models and patients with coronary artery disease. Methods: In this study, we determined the cholesterol-lowering effect of myeloid-PTP1B deletion in mice fed a high-fat high-cholesterol diet and examined effects on total cholesterol levels and lipoprotein profiles. We also determined the effects of PTP1B inhibition to oxLDL-C challenge on foam cell formation and cholesterol efflux in human monocytes/macrophages. Results: We present evidence that myeloid-PTP1B deficiency significantly increases the affinity of Kupffer cells for ApoB containing lipoproteins, in an IL10-dependent manner. We also demonstrate that PTP1B inhibitor, MSI-1436, treatment decreased foam cell formation in Thp1-derived macrophages and increased macrophage cholesterol efflux to HDL in an AMPK-dependent manner. We present evidence of three novel and distinct mechanisms regulated by PTP1B: an increase in cholesterol efflux from foam cells, decreased uptake of lipoproteins into intra-lesion macrophages in vitro and a decrease of circulating LDL-C and VLDL-C in vivo. Conclusions: Overall, these results suggest that myeloid-PTP1B inhibition has atheroprotective effects through improved cholesterol handling in atherosclerotic lesions, as well as increased reverse cholesterol transport. Trial registration Research registry, researchregistry 3235. Registered 07 November 2017, https://www.researchregistry.com/browse-the-registry#home/registrationdetails/5a01d0fce7e1904e93e0aac5/. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is notorious for its ability to develop a high level of resistance to antimicrobial agents. Resistance-nodulation-division (RND) efflux pumps could mediate drug resistance in P. aeruginosa. The present study aimed to evaluate the antibacterial and anti-efflux activities of cinnamon essential oil either alone or combined with ciprofloxacin against drug resistant P. aeruginosa originated from human and animal sources. The results revealed that 73.91% of the examined samples were positive for P. aeruginosa; among them, 77.78% were of human source and 72.73% were recovered from animal samples. According to the antimicrobial resistance profile, 48.73% of the isolates were multidrug-resistant (MDR), 9.2% were extensive drug-resistant (XDR), and 0.84% were pan drug-resistant (PDR). The antimicrobial potential of cinnamon oil against eleven XDR and one PDR P. aeruginosa isolates was assessed by the agar well diffusion assay and broth microdilution technique. The results showed strong antibacterial activity of cinnamon oil against all tested P. aeruginosa isolates with inhibition zones' diameters ranging from 34 to 50 mm. Moreover, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of cinnamon oil against P. aeruginosa isolates ranged from 0.0562–0.225 µg/mL and 0.1125–0.225 µg/mL, respectively. The cinnamon oil was further used to evaluate its anti-efflux activity against drug-resistant P. aeruginosa by phenotypic and genotypic assays. The cartwheel test revealed diminished efflux pump activity post cinnamon oil exposure by two-fold indicating its reasonable impact. Moreover, the real-time quantitative polymerase chain reaction (RT-qPCR) results demonstrated a significant (p < 0.05) decrease in the expression levels of MexA and MexB genes of P. aeruginosa isolates treated with cinnamon oil when compared to the non-treated ones (fold changes values ranged from 0.4204–0.7474 for MexA and 0.2793–0.4118 for MexB). In conclusion, we suggested the therapeutic use of cinnamon oil as a promising antibacterial and anti-efflux agent against drug-resistant P. aeruginosa. [ABSTRACT FROM AUTHOR]

Background: Serotonin (5-HT) is a biogenic monoamine with diverse functions in multiple human organs and tissues. During pregnancy, tightly regulated levels of 5-HT in the fetoplacental unit are critical for proper placental functions, fetal development, and programming. Despite being a non-neuronal organ, the placenta expresses a suite of homeostatic proteins, membrane transporters and metabolizing enzymes, to regulate monoamine levels. We hypothesized that placental 5-HT clearance is important for maintaining 5-HT levels in the fetoplacental unit. We therefore investigated placental 5-HT uptake from the umbilical circulation at physiological and supraphysiological levels as well as placental metabolism of 5-HT to 5-hydroxyindoleacetic acid (5-HIAA) and 5-HIAA efflux from trophoblast cells. Methods: We employed a systematic approach using advanced organ-, tissue-, and cellular-level models of the human placenta to investigate the transport and metabolism of 5-HT in the fetoplacental unit. Human placentas from uncomplicated term pregnancies were used for perfusion studies, culturing explants, and isolating primary trophoblast cells. Results: Using the dually perfused placenta, we observed a high and concentration-dependent placental extraction of 5-HT from the fetal circulation. Subsequently, within the placenta, 5-HT was metabolized to 5-hydroxyindoleacetic acid (5-HIAA), which was then unidirectionally excreted to the maternal circulation. In the explant cultures and primary trophoblast cells, we show concentration- and inhibitor-dependent 5-HT uptake and metabolism and subsequent 5-HIAA release into the media. Droplet digital PCR revealed that the dominant gene in all models was MAO-A, supporting the crucial role of 5-HT metabolism in placental 5-HT clearance. Conclusions: Taken together, we present transcriptional and functional evidence that the human placenta has an efficient 5-HT clearance system involving (1) removal of 5-HT from the fetal circulation by OCT3, (2) metabolism to 5-HIAA by MAO-A, and (3) selective 5-HIAA excretion to the maternal circulation via the MRP2 transporter. This synchronized mechanism is critical for regulating 5-HT in the fetoplacental unit; however, it can be compromised by external insults such as antidepressant drugs. [ABSTRACT FROM AUTHOR]

Summary: Dendritic cells (DCs) are innate immune cells that detect and process environmental signals and communicate them with T cells to bridge innate and adaptive immunity. Immune signals and microenvironmental cues shape the function of DC subsets in different contexts, which is associated with reprogramming of cellular metabolic pathways. In addition to integrating these extracellular cues to meet bioenergetic and biosynthetic demands, cellular metabolism interplays with immune signaling to shape DC‐dependent immune responses. Emerging evidence indicates that lipid metabolism serves as a key regulator of DC responses. Here, we summarize the roles of fatty acid and cholesterol metabolism, as well as selective metabolites, in orchestrating the functions of DCs. Specifically, we highlight how different lipid metabolic programs, including de novo fatty acid synthesis, fatty acid β oxidation, lipid storage, and cholesterol efflux, influence DC function in different contexts. Further, we discuss how dysregulation of lipid metabolism shapes DC intracellular signaling and contributes to the impaired DC function in the tumor microenvironment. Finally, we conclude with a discussion on key future directions for the regulation of DC biology by lipid metabolism. Insights into the connections between lipid metabolism and DC functional specialization may facilitate the development of new therapeutic strategies for human diseases. [ABSTRACT FROM AUTHOR]

Background: Niemann–Pick disease type C (NPC) is a fatal neurodegenerative disorder caused by abnormal intracellular cholesterol trafficking. Cyclodextrins (CDs), the most promising therapeutic candidates for NPC, but with concerns about ototoxicity, are cyclic oligosaccharides with dual functions of unesterified cholesterol (UC) shuttle and sink that catalytically enhance the bidirectional flux and net efflux of UC, respectively, between the cell membrane and the extracellular acceptors. However, the properties of CDs that regulate these functions and how they could be used to improve treatments for NPC are unclear. Methods: We estimated CD–UC complexation for nine CD derivatives derived from native α‐, β‐, and γ‐CD with different cavity sizes, using solubility and molecular docking analyses. The stoichiometry and complexation ability of the resulting complexes were investigated in relation to the therapeutic effectiveness and toxicity of each CD derivative in NPC experimental models. Findings: We found that shuttle and sink activities of CDs are dependent on cavity size‐dependent stoichiometry and substituent‐associated stability of CD–UC complexation. The ability of CD derivatives to form 1:1 and 2:1 complexes with UC were correlated with their ability to normalize intracellular cholesterol trafficking serving as shuttle and with their cytotoxicity associated with cellular UC efflux acting as sink, respectively, in NPC model cells. Notably, the ability of CD derivatives to form an inclusion complex with UC was responsible for not only efficacy but ototoxicity, while a representative derivative without this ability negligibly affected auditory function, underscoring its preventability. Conclusions: Our findings highlight the importance of strategies for optimizing the molecular structure of CDs to overcome this functional dilemma in the treatment of NPC. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii is a nosocomial pathogen of serious healthcare concern that is becoming increasingly difficult to treat due to antibiotic treatment failure. Recent studies have revealed that clinically defined antibiotic-susceptible strains upregulate the expression of a repertoire of putative drug efflux pumps during their growth under biologically relevant conditions, e.g., in human serum, resulting in efflux-associated resistance to physiologically achievable antibiotic levels within a patient. This phenomenon, termed Adaptive Efflux Mediated Resistance (AEMR), has been hypothesized to account for one mechanism by which antibiotic-susceptible A. baumannii fails to respond to antibiotic treatment. In the current study, we sought to identify genetic determinants that contribute to A. baumannii serum-associated AEMR by screening a transposon mutant library for members that display a loss of the AEMR phenotype. Results revealed that mutation of a putative pirin-like protein, YhaK, results in a loss of AEMR, a phenotype that could be complemented by a wild-type copy of the yhaK gene and was verified in a second strain background. Ethidium bromide efflux assays confirmed that the loss of AEMR phenotype due to pirin-like protein mutation correlated with reduced overarching efflux capacity. Further, flow cytometry and confocal microscopy measures of a fluorophore 7-(dimethylamino)-coumarin-4-acetic acid (DMACA)-tagged levofloxacin isomer, ofloxacin, further verified that YhaK mutation reduces AEMR-mediated antibiotic efflux. RNA-sequencing studies revealed that YhaK may be required for the expression of multiple efflux-associated systems, including MATE and ABC families of efflux pumps. Collectively, the data indicate that the A. baumannii YhaK pirin-like protein plays a role in modulating the organism's adaptive efflux-mediated resistance phenotype. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to investigate the feasibility of simultaneously estimating the cellular water efflux rate (kie), intracellular longitudinal relaxation rate (R10i), and intracellular volume fraction (vi) of a cell suspension using multiple samples with different gadolinium concentrations. Numerical simulation studies were conducted to assess the uncertainty in the estimation of kie, R10i, and vi from saturation recovery data using single (SC) or multiple concentrations (MC) of gadolinium‐based contrast agent (GBCA). In vitro experiments with 4 T1 murine breast cancer and SCCVII squamous cell cancer models were conducted at 11 T to compare parameter estimation using the SC protocol with that using the MC protocol. The cell lines were challenged with a Na+/K+‐ATPase inhibitor, digoxin, to assess the treatment response in terms of kie, R10i, and vi. Data analysis was conducted using the two‐compartment exchange model for parameter estimation. The simulation study data demonstrate that the MC method, compared with the SC method, reduces the uncertainty of the estimated kie by decreasing the interquartile ranges from 27.3% ± 3.7% to 18.8% ± 5.1% and the median differences from ground truth from 15.0% ± 6.3% to 7.2% ± 4.2%, while estimating R10i and vi simultaneously. In the cell studies, the MC method demonstrated reduced uncertainty in overall parameter estimation compared with the SC approach. MC method‐measured parameter changes in cells treated with digoxin increased R10i by 11.7% (p = 0.218) and kie by 5.9% (p = 0.234) for 4 T1 cells, respectively, and decreased R10i by 28.8% (p = 0.226) and kie by 1.6% (p = 0.751) for SCCVII cells, respectively. vi did not change noticeably by the treatment. The results of this study substantiate the feasibility of using saturation recovery data of multiple samples with different GBCA concentrations for simultaneous measurement of the cellular water efflux rate, intracellular volume fraction, and intracellular longitudinal relaxation rate in cancer cells. [ABSTRACT FROM AUTHOR]

Healing of the cutaneous wound requires macrophage recruitment at the sites of injury, where chemotactic migration of macrophages toward the wound is regulated by local inflammation. Recent studies suggest a positive contribution of DNA methyltransferase 1 (Dnmt1) to macrophage pro-informatory responses; however, its role in regulating macrophage motility remains unknown. In this study, myeloid-specific depletion of Dnmt1 in mice promoted cutaneous wound healing and de-suppressed the lipopolysaccharides (LPS)-inhibited macrophage motility. Dnmt1 inhibition in macrophages eliminated the LPS-stimulated changes in cellular mechanical properties in terms of elasticity and viscoelasticity. LPS increased the cellular accumulation of cholesterol in a Dnmt1-depedent manner; cholesterol content determined cellular stiffness and motility. Lipidomic analysis indicated that Dnmt1 inhibition altered the cellular lipid homeostasis, probably through down-regulating the expression of cluster of differentiation 36 CD36 (facilitating lipid influx) and up-regulating the expression of ATP-binding cassette transporter ABCA1 (mediating lipid efflux) and sterol O-acyltransferase 1 SOAT1 (also named ACAT1, catalyzing the esterification of cholesterol). Our study revealed a Dnmt1-dependent epigenetic mechanism in the control of macrophage mechanical properties and the related chemotactic motility, indicating Dnmt1 as both a marker of diseases and a potential target of therapeutic intervention for wound healing. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic-resistant bacteria and hospital-acquired bacterial infection has become rampant due to antibiotic overuse. Virulence factors are secondary to bacterial growth and are important in their pathogenesis, and therefore, new antimicrobial therapies to inhibit bacterial virulence factors are becoming important strategies against antibiotic resistance. Here, we focus on anti-virulence factors that act through anti-quorum sensing and the subsequent clearance of bacteria by antimicrobial compounds, especially active herbal extracts. These quorum sensing systems are based on toxins, biofilms, and efflux pumps, and bioactive compounds isolated from medicinal plants can treat bacterial virulence pathologies. Ideally, bacterial virulence factors are secondary growth factors of bacteria. Hence, inhibition of bacterial virulence factors could reduce bacterial pathogenesis. Furthermore, anti-virulence factors from herbal compounds can be developed as novel treatments for bacterial infection. Therefore, this narrative review aims to discuss bacterial virulence factors acting through quorum sensing systems that are preserved as targets for treating bacterial infection by plant-derived compounds. [ABSTRACT FROM AUTHOR]

(-)-α-Bisabolol is naturally occurring in many plants and has great potential in health products and pharmaceuticals. However, the current extraction method from natural plants is unsustainable and cannot fulfil the increasing requirement. This study aimed to develop a sustainable strategy to enhance the biosynthesis of (-)-α-bisabolol by metabolic engineering. By introducing the heterologous gene MrBBS and weakening the competitive pathway gene ERG9, a de novo (-)-α-bisabolol biosynthesis strain was constructed that could produce 221.96 mg/L (-)-α-bisabolol. Two key genes for (-)-α-bisabolol biosynthesis, ERG20 and MrBBS, were fused by a flexible linker (GGGS)3 under the GAL7 promoter control, and the titer was increased by 2.9-fold. Optimization of the mevalonic acid pathway and multi-copy integration further increased (-)-α-bisabolol production. To promote product efflux, overexpression of PDR15 led to an increase in extracellular production. Combined with the optimal strategy, (-)-α-bisabolol production in a 5 L bioreactor reached 7.02 g/L, which is the highest titer reported in yeast to date. This work provides a reference for the efficient production of (-)-α-bisabolol in yeast. [ABSTRACT FROM AUTHOR]

Background: Due to the substantial increase in the use of disinfectants containing quaternary ammonion compounds (QACs) in healthcare and community settings during the COVID-19 pandemic, there is increased concern that heavy use might cause bacteria to develop resistance to QACs or contribute to antibiotic resistance. The purpose of this review is to briefly discuss the mechanisms of QAC tolerance and resistance, laboratory-based evidence of tolerance and resistance, their occurrence in healthcare and other real-world settings, and the possible impact of QAC use on antibiotic resistance. Methods: A literature search was conducted using the PubMed database. The search was limited to English language articles dealing with tolerance or resistance to QACs present in disinfectants or antiseptics, and potential impact on antibiotic resistance. The review covered the period from 2000 to mid-Jan 2023. Results: Mechanisms of QAC tolerance or resistance include innate bacterial cell wall structure, changes in cell membrane structure and function, efflux pumps, biofilm formation, and QAC degradation. In vitro studies have helped elucidate how bacteria can develop tolerance or resistance to QACs and antibiotics. While relatively uncommon, multiple episodes of contaminated in-use disinfectants and antiseptics, which are often due to inappropriate use of products, have caused outbreaks of healthcare-associated infections. Several studies have identified a correlation between benzalkonium chloride (BAC) tolerance and clinically-defined antibiotic resistance. The occurrence of mobile genetic determinants carrying multiple genes that encode for QAC or antibiotic tolerance raises the concern that widespread QAC use might facilitate the emergence of antibiotic resistance. Despite some evidence from laboratory-based studies, there is insufficient evidence in real-world settings to conclude that frequent use of QAC disinfectants and antiseptics has promoted widespread emergence of antibiotic resistance. Conclusions: Laboratory studies have identified multiple mechanisms by which bacteria can develop tolerance or resistance to QACs and antibiotics. De novo development of tolerance or resistance in real-world settings is uncommon. Increased attention to proper use of disinfectants is needed to prevent contamination of QAC disinfectants. Additional research is needed to answer many questions and concerns related to use of QAC disinfectants and their potential impact on antibiotic resistance. [ABSTRACT FROM AUTHOR]

Background Common genetic variants of the enzymes and efflux pump involved in tacrolimus disposition have been associated with calcineurin inhibitor nephrotoxicity, but their importance is unclear because of the multifactorial background of renal fibrosis. This study explores the pro-fibrotic response of tacrolimus exposure in relation to the differential capacity for tacrolimus metabolism in proximal tubule cells (PTCs) with a variable (pharmaco)genetic background. Methods PTCs were obtained from protocol allograft biopsies with different combinations of CYP3A5 and ABCB1 variants and were incubated with tacrolimus within the concentration range found in vivo. Gene and protein expression, CYP3A5 and P-glycoprotein function, and tacrolimus metabolites were measured in PTC. Connective tissue growth factor (CTGF) expression was assessed in protocol biopsies of kidney allograft recipients. Results PTCs produce CTGF in response to escalating tacrolimus exposure, which is approximately 2-fold higher in cells with the CYP3A5*1 and ABCB1 TT combination in vitro. Increasing tacrolimus exposure results in relative higher generation of the main tacrolimus metabolite {13-O-desmethyl tacrolimus [M1]} in cells with this same genetic background. Protocol biopsies show a larger increase in in vivo CTGF tissue expression over time in TT vs. CC/CT but was not affected by the CYP3A5 genotype. Conclusions Tacrolimus exposure induces a pro-fibrotic response in a PTC model in function of the donor pharmacogenetic background associated with tacrolimus metabolism. This finding provides a mechanistic insight into the nephrotoxicity associated with tacrolimus treatment and offers opportunities for a tailored immunosuppressive treatment. [ABSTRACT FROM AUTHOR]

Background: The pathogenesis of inflammatory bowel disease may be associated with the disruption in interactions between the immune system and gut flora. Epigenetic mechanisms especially, DNA methylation appear to be significant regarding the interaction between the environment and genome. ABCB1 is the encoding gene for multi-drug resistance protein 1 (MDR1) (P-glycoprotein), which is an important transmembrane protein responsible for the efflux of cellular molecules from the intestinal wall to the lumen. Method: In this study, we compared the methylation status of the promoter of ABCB1 in rectal mucosa of patients with ulcerative colitis (UC) and healthy controls by using the bisulfite conversion system and real-time quantitative multiplex methylation-specific PCR (QM-MSP). Results: We demonstrated that the mucosal specimen of 26 UC patients had significantly higher levels of promoter methylation in comparison to 26 controls. Conclusion: As the first investigation of Iranian patients with UC, we showed that patients had higher levels of ABCB1 promoter methylation in their inflammatory rectal mucosa compared to controls. However, this altered state of methylation did not associate with the characteristics of the patients such as age and sex. Our findings are a basis for further studies on concurrent assessment of promoter methylation and expression of ABCB1 in UC. [ABSTRACT FROM AUTHOR]

ATP‐binding cassette (ABC) transporters are expressed in various human tissues and play a vital role in the efflux of various chemotherapeutic drugs. The current study has assessed genetic variants of ABCB1, ABCC1, ABCC2, and ABCG2 genes in 407 lung cancer patients undergoing platinum‐based doublet chemotherapy. The association of ABCB1 (C1236T, C3435T, and G2677T/A), ABCC1 (G3173A and G2168A),ABCC2 (G4544A), and ABCG2 (C421A) polymorphisms with chemotherapy‐induced adverse events were assessed, and statistical analysis was conducted. Our data showed that patients harboring heterozygous (GA) genotype for ABCC1 G3173A had an increased risk of developing leukopenia (odds ratio [OR] = 1.88, p = 0.04) and anemia (adjusted odds ratio [AOR] = 2.70, p = 0.03). For ABCC2 G4544A polymorphism, patients harboring one copy of the mutant (GA) allele showed an increased risk of developing anemia (OR = 4.24, p = 0.03). After adjusting with various confounding factors, the heterozygous (GA) genotype showed a 5.63‐fold increased risk of developing anemia (AOR = 5.63, p = 0.03). The ABCB1 G2677A (OR = 0.37, p = 0.008) and ABCC1 G3173A (OR = 0.54, p = 0.04) polymorphism showed a lower incidence of developing nephrotoxicity. In ABCG2 C421A polymorphism, patients harboring heterozygous (CA) genotype had a lower incidence of having diarrhea (OR = 0.25, p = 0.04). An increased risk of having diarrhea was observed in the heterozygous genotype (GA) for ABCC1 G3173A polymorphism (AOR = 2.78, p = 0.04). An increased risk of liver injury was found in the patients carrying heterozygous genotype of the ABCC1 G3173A (OR = 2.06, p = 0.02) and ABCB1 C1236T (OR = 1.85, p = 0.01). This study demonstrates the role of polymorphic variations in ABCB1, ABCC1, ABCC2, and ABCG2 in predicting hematological, nephrotoxicity, gastrointestinal, and hepatotoxicity. [ABSTRACT FROM AUTHOR]

Efflux pumps are a specialized tool of antibiotic resistance used by Pseudomonas aeruginosa to expel antibiotics. The current study was therefore conducted to examine the expression of MexAB-OprM and MexCD-OprJ efflux pump genes. In this study, 200 samples were collected from Khyber Teaching Hospital (KTH) and Hayatabad Medical Complex (HMC) in Peshawar, Pakistan. All the isolates were biochemically identified by an Analytical Profile Index kit and at the molecular level by Polymerase Chain Reaction (PCR) utilizing specific primers for the OprL gene. A total of 26 antibiotics were tested in the current study using the guidelines of the Clinical and Laboratory Standard Institute (CLSI) and high-level resistance was shown to amoxicillin-clavulanic acid (89%) and low-level to chloramphenicol (1%) by the isolates. The antibiotic-resistant efflux pump genes MexA, MexB, OprM, MexR, MexC, MexD, OprJ, and NfxB were detected in 178 amoxicillin-clavulanic acid-resistant isolates. Mutations were detected in MexA, MexB, and OprM genes but no mutation was found in the MexR gene as analyzed by I-Mutant software. Statistical analysis determined the association of antibiotics susceptibility patterns by ANOVA: Single Factor p = 0.05. The in silico mutation impact on the protein structure stability was determined via the Dynamut server, which revealed the mutations might increase the structural stability of the mutants. The docking analysis reported that MexA wild protein showed a binding energy value of −6.1 kcal/mol with meropenem and the mexA mutant (E178K) value is −6.5 kcal/mol. The mexB wild and mutant binding energy value was −5.7 kcal/mol and −8.0 kcal/mol, respectively. Efflux pumps provide resistance against a wide range of antibiotics. Determining the molecular mechanisms of resistance in P. aeruginosa regularly will contribute to the efforts against the spread of antibiotic resistance globally. [ABSTRACT FROM AUTHOR]

Campylobacter (C.) spp. are the most important foodborne, bacterial, and zoonotic pathogens worldwide. Resistance monitoring of foodborne bacterial pathogens is an important tool to control antimicrobial resistance as a part of the "One Health" approach. The detection and functionality of new resistance genes are of paramount importance in applying more effective screening methods based on whole genome sequencing (WGS). Most tetracycline-resistant C. spp. isolates harbor tet(O), a gene that encodes a ribosomal protection protein. Here we describe tet(O)_3, which has been identified in two food isolates of C. jejuni and is very similar to the tet(O) gene in Streptococcus pneumoniae, having a truncated promoter sequence. This gene confers resistance to tetracycline below 1 mg/L, which is the epidemiological cut-off value. We have analyzed the entire genome of these two isolates, together with a C. jejuni isolate found to have high-level resistance to tetracycline. In contrast to the highly resistant isolate, the promoter of tet(O)_3 is highly responsive to tetracycline, as observed by reverse transcription polymerase chain reaction (RT-PCR). In addition, the two isolates possess a CRISPR repeat, fluoroquinolone resistance due to the gyrA point mutation C257T, a β-lactamase resistance gene blaOXA-184, a multidrug efflux pump CmeABC and its repressor CmeR, but no plasmid. Low-level antibiotic resistant C. jejuni might therefore have an advantage for surviving in non-host environments. [ABSTRACT FROM AUTHOR]

Background & objectives: Drug-resistant tuberculosis (TB) jeopardizes the treatment process with poor outcomes. Efflux pumps (EPs) belonging to the ABC transporter family in Mycobacterium tuberculosis confer resistance to rifampicin (RMP) besides genetic mutations thus serving as a target for a potential adjunct therapeutic inhibitory molecule. Rv1218c is one such pump that was previously reported to be active in multidrug-resistant TB clinical isolates. Methods: In this study, the inhibition potential of Rv1218c-EP was tested on 8 molecules that were shortlisted by in silico methods. These molecules were subjected to the minimum inhibitory concentration (MIC) determination, checkerboard drug combination assay, ethidium bromide-DNA binding assay, and in vitro and ex vivo cytotoxicity assay. Results: Based on the outcome of the study, two molecules dodecanoic acid (DA) and palmitic acid (PA) were found to be potential enough to decrease the MIC of RMP by 8 to 1000 folds against multidrugresistant clinical isolates and Rv1218c expressing recombinant Mycobacterium smegmatis. Interpretation & conclusions: These molecules were also found to reduce the time taken by RMP to kill these drug-resistant Mycobacteria to 48 h, unlike control isolates that survived more than 240 h of RMP exposure. The functional concentration of both molecules was non-toxic to the epithelial and blood mononuclear cells. With further comprehensive scientific validation, PA and DA could be recommended as adjunct therapeutic molecules with first-line anti-TB drugs to treat drug-resistant TB. [ABSTRACT FROM AUTHOR]

• miR-495-3p inhibits leukemic cell growth and is downregulated in BCR-ABL1 -expressing cell lines. • miR-495-3p modulates responses to tyrosine kinase inhibitor treatment, including those in UT-7 cells expressing T315I. • Overexpression of miR-495-3p leads to a decrease ofin MDR1 expression and drug efflux activity. • Bioinformatics analyses revealed that miR-495-3p targets genes that are upregulated in blast crisis. Chronic myeloid leukemia (CML) is a clonal hematopoietic malignancy driven by the BCR-ABL1 fusion oncoprotein. The development of tyrosine kinase inhibitors (TKIs) has deeply increased long-term survival of CML patients. Nonetheless, one patient out of four will switch TKI off owing either to drug intolerance or resistance partly due to amplification or mutations of BCR-ABL1 oncogene and alteration in ATP-binding cassette (ABC) transporters. Increasing evidence suggests the involvement of the microRNA miR-495-3p in cancer-associated chemoresistance through multidrug resistance 1 (MDR1) gene, which encodes an ATP-dependent efflux pump. Our study aimed at investigating the potential role of miR-495-3p in CML TKI chemo-sensitivity and determining the underlying molecular circuitry involved. We first observed that miR-495-3p expression was lower in BCR-ABL1 -expressing cellular models in vitro. Notably, loss-of-function experiments showed increased proliferation associated with a decreased number of nondividing cells (G0/G1) and resistance to Imatinib. Conversely, our data showed that miR-495-3p overexpression hindered leukemic cell growth and TKI resistance in Imatinib-resistant T315I-mutant cells, as well as drug efflux activity through MDR1 regulation. Further investigating the role of miR-495-3p in CML patients, we found that predicted miR-495-3p targets were upregulated in patients in blast crisis that were involved in protein phosphorylation and associated with the worst prognosis. Taken together, our results demonstrate that downregulation of miR-495-3p expression is important in the malignant phenotype of CML and TKI resistance mechanisms and could be a useful biomarker and a potential therapeutic target to eradicate CML. [Display omitted] [ABSTRACT FROM AUTHOR]

During the process of adapting to metal contamination, plants produce secondary metabolites that have the potential to modulate multidrug-resistant (MDR) phenotypes; this is achieved by inhibiting the activity of efflux pumps to reduce the minimum inhibitory concentrations (MICs) of antimicrobial substrates. Our study evaluated the effect of secondary metabolites of belowground parts of Pteris vittata L. and Fallopia japonica, two metal-tolerant plants from northern Vietnam, on six antibiotic-resistant Stenotrophomonas maltophilia strains possessing efflux pump resistance mechanisms that were isolated from soil and clinical samples. The chemical composition of aqueous and dichloromethane (DCM) fractions extracted from P. vittata and F. japonica was determined using UHPLC-DAD-ESI/QTOF analysis. The antibacterial and efflux pump inhibitory activities of the four fractions were evaluated for the six strains (K279a, 0366, BurA1, BurE1, PierC1, and 502) using a microdilution assay at fraction concentrations of 62.5, 125, and 250 μg/mL. The DCM fraction of F. japonica exhibited remarkable antibacterial activity against strain 0366, with a MIC of 31.25 μg/mL. Furthermore, this fraction also significantly decreased gentamicin MIC: four-fold and eight-fold reductions for BurA1 and BurE1 strains, respectively (when tested at 250 μg/mL), and two-fold and eight-fold reductions for K279a and BurE1 strains, respectively (when tested at 125 μg/mL). Pure emodin, the main component identified in the DCM fraction of F. japonica, and sennidine A&B only reduced by half the MIC of gentamicin (when tested at 30 μg/mL). Our results suggest that the DCM fraction components of F. japonica underground parts may be potential candidates for new bacterial efflux pump inhibitors (EPIs). [ABSTRACT FROM AUTHOR]

Expelling antibiotic molecules out of the cell wall through multiple efflux pumps is one of the potential mechanisms of developing resistance against a wide number of antibiotics in Staphylococcus aureus. The aim of this study was to investigate the association between the antibiotic susceptibility profile and the prevalence of different efflux pump genes i.e., norA, norB, norC, mepA, sepA, mdeA, qacA/B, and smr in the clinical isolates of S. aureus. Sixty clinical isolates were collected from a tertiary level hospital in Bangladesh. The disc diffusion method using ten antibiotics of different classes was used to discern the susceptibility profile. polymerase chain reaction (PCR) was employed to observe the resistance patterns and to detect the presence of plasmid and chromosomal encoded genes. Among the clinical isolates, 60% (36 out of 60) of the samples were Methicillin-resistant Staphylococcus aureus (MRSA), whereas 55% (33 out of 60) of the bacterial samples were found to be multi-drug resistant. The bacteria showed higher resistance to vancomycin (73.33%), followed by ciprofloxacin (60%), cefixime (53.33%), azithromycin (43.33%), and amoxicillin (31.67%). The prevalence of the chromosomally-encoded efflux genes norA (91.67%), norB (90%), norC (93.33%), mepA (93.33%), sepA (98.33%), and mdeA (93.33%) were extremely high with a minor portion of them carrying the plasmid-encoded genes qacA/B (20%) and smr (8.33%). Several genetic combinations of efflux pump genes were revealed, among which norA + norB + norC + mepA + sepA + mdeA was the most widely distributed combination among MRSA and MSSA bacteria that conferred resistance against ciprofloxacin and probably vancomycin. Based on the present study, it is evident that the presence of multiple efflux genes potentiated the drug extrusion activity and may play a pivotal role in the development of multidrug resistance in S. aureus. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis (RA) is an inflammatory disease requiring treatment by disease-modifying agents like methotrexate. C3435T is a single nucleotide polymorphism in the ABCB1 gene that affects the expression of the Pglycoprotein responsible for the efflux of several drugs from cells increasing both its action and toxicity. Objective: Examine the frequency of C3435T in RA patients and assess its influence on responsiveness to methotrexate treatment and occurrence of methotrexate adverse effects. Patients and Methods: Genotyping C3435T polymorphism was done by real-time polymerase chain reaction and the frequency of the polymorphism was assessed in a sample of 90 RA patients who have received methotrexate treatment and 90 healthy controls. The prevalence of the polymorphism was also assessed in responders to methotrexate compared to non-responders, and also in patients who suffered from methotrexate side effects compared to those who did not. Results: The CC was the most frequent genotype in patients (47.8%) while the CT was the most frequent in controls (43.3%), however, no association was found between the ABCB1 C3435T genotype and susceptibility to RA under the different genetic models (p>0.05). Even though the patients who responded to methotrexate had a higher frequency of the T allele (38.9%) compared to non-responders (27.8%), the genotype and allele frequency were not associated with response to methotrexate (p>0.05). Also, no association was observed between the frequency of the C3435T polymorphism and experiencing methotrexate-associated adverse effects (p>0.05). Conclusion: The C3435T polymorphism of the ABCB1 gene may not be a genetic risk factor for RA and does not affect responsiveness to methotrexate or affect the occurrence of adverse effects from the drug. [ABSTRACT FROM AUTHOR]

We introduce a new 1H2O magnetic resonance approach: metabolic activity diffusion imaging (MADI). Numerical diffusion‐weighted imaging decay simulations characterized by the mean cellular water efflux (unidirectional) rate constant (kio), mean cell volume (V), and cell number density (ρ) are produced from Monte Carlo random walks in virtual stochastically sized/shaped cell ensembles. Because of active steady‐state trans‐membrane water cycling (AWC), kio reflects the cytolemmal Na+, K+ATPase (NKA) homeostatic cellular metabolic rate (cMRNKA). A digital 3D "library" contains thousands of simulated single diffusion‐encoded (SDE) decays. Library entries match well with disparate, animal, and human experimental SDE decays. The V and ρ values are consistent with estimates from pertinent in vitro cytometric and ex vivo histopathological literature: in vivo V and ρ values were previously unavailable. The library allows noniterative pixel‐by‐pixel experimental SDE decay library matchings that can be used to advantage. They yield proof‐of‐concept MADI parametric mappings of the awake, resting human brain. These reflect the tissue morphology seen in conventional MRI. While V is larger in gray matter (GM) than in white matter (WM), the reverse is true for ρ. Many brain structures have kio values too large for current, invasive methods. For example, the median WM kio is 22s−1; likely reflecting mostly exchange within myelin. The kio•V product map displays brain tissue cMRNKA variation. The GM activity correlates, quantitatively and qualitatively, with the analogous resting‐state brain 18FDG‐PET tissue glucose consumption rate (tMRglucose) map; but noninvasively, with higher spatial resolution, and no pharmacokinetic requirement. The cortex, thalamus, putamen, and caudate exhibit elevated metabolic activity. MADI accuracy and precision are assessed. The results are contextualized with literature overall homeostatic brain glucose consumption and ATP production/consumption measures. The MADI/PET results suggest different GM and WM metabolic pathways. Preliminary human prostate results are also presented. [ABSTRACT FROM AUTHOR]

Lisinopril is an antihypertensive drug with poor intestinal permeability. Enhancement of intestinal absorption depends on a clear understanding of the permeation pathways and absorption mechanisms. Unfortunately, these are not fully elucidated for lisinopril. Accordingly, the aim was to determine lisinopril permeation pathways and obstacles limiting membrane transport with subsequent nomination of appropriate permeation enhancers. This employed an in situ rabbit intestinal perfusion technique, which revealed site‐dependent absorptive clearance (PeA/L) from a lisinopril simple solution (5 μg/ml), with paracellular absorption playing a role. Regional drug permeability ranked as colon> duodenum> jejunum> ileum opposing intestinal expression rank of P‐glycoprotein (P‐gp) efflux transporters. Duodenal and jejunal perfusion of a higher lisinopril concentration (50 μg/ml) reflected saturable absorption, suggesting carrier‐mediated transport. The effect of piperine and verapamil as P‐gp inhibitors on intestinal absorption of lisinopril was investigated. Coperfusion with either piperine or verapamil significantly enhanced lisinopril absorption, with enhancement being dominant in the ileum segment. This supported the contribution of P‐gp transporters to poor lisinopril permeability. On the other hand, coperfusion of lisinopril with zinc acetate dihydrate significantly multiplied lisinopril PeA/L by 2.3‐ and 6.6‐fold in duodenum and ileum segments, respectively, through magnifying intestinal water flux. The study explored the barriers limiting lisinopril intestinal absorption. Moreover, the study exposed clinically relevant lisinopril interactions with common coadministered cargos that should be considered for an appropriate lisinopril regimen. However, this requires further in vivo verification. [ABSTRACT FROM AUTHOR]

The pro-inflammatory status of adipose tissue (AT) has been found to be related to reverse cholesterol transport (RCT) from peritoneal macrophages. However, this finding was made in experimental models using induced peritonitis and isolated peritoneal macrophages of animals. This experimental relationship is in agreement with RCT changes in man in two extreme situations, sepsis or cardiovascular complications. Given the above, we sought to test RTC in relationship to macrophage polarization in the visceral AT (VAT) of living kidney donors (LKDs) and the effect of conditioned media obtained from their AT. The influence of ATCM on CE capacity was first assessed in an experiment where standard plasma was used as cholesterol acceptor from [14C] cholesterol labeled THP-1 cells. Conditioned media as a product of LKDs' incubated AT showed no effect on CE. Likewise, we did not find any effect of individual plasma of LKDs on CE when individual plasma of LKDs were used as acceptors. On the other hand, we documented an effect of LKDs' adipose cell size on CE. Our results indicate that the pro-inflammatory status of human AT is not likely induced by disrupted RCT but might be influenced by the metabolic status of LKDs' adipose tissue. [ABSTRACT FROM AUTHOR]

• A higher prevalence of MDR-NTHi strains is observed in northern Taiwan. • New transposons conferring AMP, TET, and CHL resistance are identified. • Efflux pumps contribute to NTHi resistance to cephems, carbapenems, and macrolides. Nontypeable Haemophilus influenzae (NTHi), once considered a harmless commensal, has emerged as a significant concern due to the increased prevalence of multidrug-resistant (MDR) strains and their association with invasive infections. This study aimed to explore the epidemiology and molecular resistance mechanisms of 51 NTHi isolates collected from patients with invasive infections in northern Taiwan between 2011 and 2020. This investigation revealed substantial genetic diversity, encompassing 29 distinct sequence types and 18 clonal complexes. Notably, 68.6% of the isolates exhibited ampicillin resistance, with 28 categorised as MDR and four isolates were even resistant to up to six antibiotic classes. Among the MDR isolates, 18 pulsotypes were identified, indicating diverse genetic lineages. Elucidation of their resistance mechanisms revealed 18 β-lactamase-producing amoxicillin–clavulanate-resistant (BLPACR) isolates, 12 β-lactamase-producing ampicillin-resistant (BLPAR) isolates, and 5 β-lactamase-nonproducing ampicillin-resistant (BLNAR) isolates. PBP3 analysis revealed 22 unique substitutions in BLPACR and BLNAR, potentially contributing to cephem resistance. Notably, novel transposons, Tn 7736 -Tn 7739 , which contain critical resistance genes, were discovered. Three strains harboured Tn 7739 , containing seven resistance genes [ aph(3′)-Ia, bla TEM-1 , catA, sul2, strA, strB , and tet (B)], while four other strains carried Tn 7736 , Tn 7737 , and Tn 7738 , each containing three resistance genes [ bla TEM-1 , catA , and tet (B)]. The emergence of these novel transposons underscores the alarming threat posed by highly resistant NTHi strains. Our findings indicated that robust surveillance and comprehensive genomic studies are needed to address this growing public health challenge. [Display omitted] [ABSTRACT FROM AUTHOR]

The emergence of antimicrobial resistance (AMR) in clinical microbes has led to a search for novel antibiotics for combating bacterial infections. The treatment of bacterial infections becomes more challenging with the onset of biofilm formation. AMR is further accelerated by biofilm physiology and differential gene expression in bacteria with an inherent resistance to conventional antibiotics. In the search for innovative strategies to control the spread of AMR in clinical isolates, plant-derived therapeutic metabolites can be repurposed to control biofilm-associated drug resistance. Unlike antibiotics, designed to act on a single cellular process, phytochemicals can simultaneously target multiple cellular components. Furthermore, they can disrupt biofilm formation and inhibit quorum sensing, offering a comprehensive approach to combat bacterial infections. In bacterial biofilms, the first line of AMR is due to biofilms associated with the extracellular matrix, diffusion barriers, quorum sensing, and persister cells. These extracellular barriers can be overcome using phytochemical-based antibiotic adjuvants to increase the efficacy of antibiotic treatment and restrict the spread of AMR. Furthermore, phytochemicals can be used to target bacterial intracellular machinery such as DNA replication, protein synthesis, efflux pumps, and degrading enzymes. In parallel with pristine phytochemicals, phyto-derived nanomaterials have emerged as an effective means of fighting bacterial biofilms. These nanomaterials can be formulated to cross the biofilm barriers and function on cellular targets. This review focuses on the synergistic effects of phytochemicals and phyto-derived nanomaterials in controlling the progression of biofilm-related AMR. IT provides comprehensive insights into recent advancements and the underlying mechanisms of the use of phyto-derived adjuvants and nanomaterials. [Display omitted] • Pathogenic bacteria use biofilm for diseases establishment, which enhances their antibiotics resistance. • Presence of bacterial biofilms in any infection can cause an increase in the pathogenicity of the microbe. • Phyto-antimicrobial can be used as antibiotic-adjuvants and potentiators against bacterial biofilms • Phyto-derived nanomaterials/drugs have enormous potential to control and cure infection by targeting quorum sensing and EPS synthesis in biofilms. [ABSTRACT FROM AUTHOR]

As the most abundant cation in archaeal, bacterial, and eukaryotic cells, potassium (K+) is an essential element for life. While much is known about the machinery of transcellular and paracellular K transport–channels, pumps, co-transporters, and tight-junction proteins—many quantitative aspects of K homeostasis in biological systems remain poorly constrained. Here we present measurements of the stable isotope ratios of potassium (41K/39K) in three biological systems (algae, fish, and mammals). When considered in the context of our current understanding of plausible mechanisms of K isotope fractionation and K+ transport in these biological systems, our results provide evidence that the fractionation of K isotopes depends on transport pathway and transmembrane transport machinery. Specifically, we find that passive transport of K+ down its electrochemical potential through channels and pores in tight-junctions at favors 39K, a result which we attribute to a kinetic isotope effect associated with dehydration and/or size selectivity at the channel/pore entrance. In contrast, we find that transport of K+ against its electrochemical gradient via pumps and co-transporters is associated with less/no isotopic fractionation, a result that we attribute to small equilibrium isotope effects that are expressed in pumps/co-transporters due to their slower turnover rate and the relatively long residence time of K+ in the ion pocket. These results indicate that stable K isotopes may be able to provide quantitative constraints on transporter-specific K+ fluxes (e.g., the fraction of K efflux from a tissue by channels vs. co-transporters) and how these fluxes change in different physiological states. In addition, precise determination of K isotope effects associated with K+ transport via channels, pumps, and co-transporters may provide unique constraints on the mechanisms of K transport that could be tested with steered molecular dynamic simulations. [ABSTRACT FROM AUTHOR]

Aim: Pacific hagfish are exceptionally tolerant to high environmental ammonia (HEA). Here, we elucidated a cellular mechanism that enables hagfish to actively excrete ammonia against steep ammonia gradients expected to be found inside a decomposing whale carcass. Methods: Hagfish were exposed to varying concentrations of HEA in the presence or absence of environmental Na+, while plasma ammonia levels were tracked. 14C‐methylammonium was used as a proxy for NH4+ to measure efflux in whole animals and in isolated gill pouches; the latter allowed us to assess the effects of amiloride specifically on Na+/H+ exchangers (NHEs) in gill cells. Western blotting and immunohistochemistry were utilized to evaluate the abundance and sub‐cellular localization of Rhesus glycoprotein (Rh) channels in the response to HEA. Results: Hagfish actively excreted NH4+ against steep inwardly directed ENH4+ (ΔENH4+ ~ 35 mV) and pNH3 (ΔpNH3 ~ 2000 μtorr) gradients. Active NH4+ excretion and plasma ammonia hypo‐regulation were contingent on the presence of environmental Na+, indicating a Na+/NH4+ exchange mechanism. Active NH4+ excretion across isolated gill pouches was amiloride‐sensitive. Exposure to HEA resulted in decreased abundance of Rh channels in the apical membrane of gill ionocytes. Conclusions: During HEA exposure, hagfish can actively excrete ammonia against a steep concentration gradient using apical NHEs energized by Na+‐K+‐ATPase in gill ionocytes. Additionally, apical Rh channels are removed from the apical membrane, presumably to reduce ammonia loading from the environment. We suggest that this mechanism allows hagfish to maintain tolerable ammonia levels while feeding inside decomposing carrion, allowing them to exploit nutrient‐rich food‐falls. [ABSTRACT FROM AUTHOR]