Mechanisms and Consequences of Macromolecular Phase Separation.

Over a century ago, colloidal phase separation of matter into non-membranous bodies was recognized as a fundamental organizing principal of cell "protoplasm." Recent insights into the molecular properties of such phase-separated bodies present challenges to our understanding of cellular protein interaction networks, as well as opportunities for interpreting and understanding of native and pathological genetic and molecular interactions. Here, we briefly review examples of and discuss physical principles of phase-separated cellular bodies and then reflect on how knowledge of these principles may direct future research on their functions.

Dequalinium Chloride for the Treatment of Vulvovaginal Infections: A Systematic Review and Meta-Analysis.

OBJECTIVE/PURPOSE: Women at reproductive age frequently experience vulvovaginal infections and vaginitis. The most common etiologies are vulvovaginal candidiasis (VVC), bacterial vaginosis (BV), desquamative inflammatory vaginitis/aerobic vaginitis, and trichomoniasis. Various treatment options are available for these infections, such as specific antimicrobial or antiseptic agents. Dequalinium chloride (DQC) is a local antiseptic agent with a broad antimicrobial and antifungal spectrum. Multiple studies suggest that DQC is an efficient treatment for vaginal infections; however, it is not widely recommended as a first-line treatment. This systematic review and meta-analysis aims to evaluate the efficacy of DQC compared with that of standard treatment. METHODS: Our systematic review was conducted according to the PRISMA guidelines. PubMed/MEDLINE, EMBASE, CENTRAL, and clinicaltrials.org were searched to retrieve relevant reports up to October 2022. RESULTS: Four randomized controlled studies and 1 observational study were included in this review. Overall, DQC showed noninferiority to the reference treatments for BV and VVC, and to the evaluated treatment options for desquamative inflammatory vaginitis/aerobic vaginitis. For BV and VVC, this could also be confirmed in a meta-analysis including 3 randomized controlled studies. No serious adverse events were reported in any of these studies. CONCLUSIONS: Dequalinium chloride offers a safe, well-tolerated, and efficient treatment option for vulvovaginal infections of different etiologies. However, further studies are needed to confirm our findings and allow inclusion of DQC as a first-line treatment into guidelines.

COMPARISON OF THE IMPACT OF ANTISEPTIC AGENTS ON GARDNERELLA VAGINALIS AND ATOPOBIUM VAGINAE DETECTED IN THE ORAL CAVITY OF WOMEN WITH BACTERIAL VAGINOSIS.

When women with comorbid bacterial vaginosis visit periodontologist, it is essential to understand the presence of cross-infection processes between the oral cavity and vagina in this particular category of subjects. Conducting detection of Gardnerella vaginalis and Atopobium vaginae, which are provocative microbial factors for bacterial vaginosis, is a mandatory step in the laboratory examination of subjects. When choosing an antiseptic for oral cavity disinfection, the use of 0.25% dequalinium chloride is more advisable. Both subjective and objective examination methods thoroughly demonstrate the higher clinical effectiveness of 0.25% dequalinium chloride: patients report a 20% more frequent improvement in subjective indicators, the index assessment of periodontal status improves by 1.2-1.6 times, and the detection rate of Gardnerella vaginalis and Atopobium vaginae is by 20% lower compared to 0.2% chlorhexidine. The specific composition of oral microbiota in this group of subjects necessitates adjustments to treatment protocols and consideration of the specific impact on Gardnerella vaginalis and Atopobium vaginae.

HIV-1 fusion inhibitors targeting the membrane-proximal external region of Env spikes.

Combination antiretroviral therapy has transformed HIV-1 infection, once a fatal illness, into a manageable chronic condition. Drug resistance, severe side effects and treatment noncompliance bring challenges to combination antiretroviral therapy implementation in clinical settings and indicate the need for additional molecular targets. Here, we have identified several small-molecule fusion inhibitors, guided by a neutralizing antibody, against an extensively studied vaccine target-the membrane proximal external region (MPER) of the HIV-1 envelope spike. These compounds specifically inhibit the HIV-1 envelope-mediated membrane fusion by blocking CD4-induced conformational changes. An NMR structure of one compound complexed with a trimeric MPER construct reveals that the compound partially inserts into a hydrophobic pocket formed exclusively by the MPER residues, thereby stabilizing its prefusion conformation. These results suggest that the MPER is a potential therapeutic target for developing fusion inhibitors and that strategies employing an antibody-guided search for novel therapeutics may be applied to other human diseases.

Dequalinium chloride use in adult Spanish women with bacterial vaginosis: an observational study.

Bacterial vaginosis (BV) represents the most frequent vaginal infection in women of childbearing age. The aim of this study was to characterise episodes of BV among adult Spanish women and their management with dequalinium chloride (DQC). Data from 573 DQC-treated BV adult women was obtained on medical records and questionnaires. The study shows that 20.6% had presented vaginal infections previously. Comorbid candidosis was significantly associated to other symptoms, such as pruritus or leucorrhoea. Most patients (64.3%) indicated a moderate-strong impact of the BV episode on their sexual life. After treatment, 84.8% of patients reported no BV symptoms. Patients were given instructions to prevent relapses. Most patients (83.1%) rated DQC as 'satisfactory' or 'very/extremely satisfactory' regarding symptom relief, prevention or treatment of the episode of BV. In conclusion, this study provides a better understanding of BV episodes and the impact of the treatment with DQC in real clinical practice in Spanish patients.IMPACT STATEMENTWhat is already known on this subject? Bacterial vaginosis (BV) is the most commonly reported vaginal infection among women of childbearing age. Despite the availability of antibiotic medications for the treatment of BV, management of this condition remains challenging. In fact, recurrence of BV has been reported for up to 50% of cases. However, antiseptic agents are considered an effective option for BV treatment.What the results of this study add? The study provides a better understanding of the prevalent symptomatology and the impact on quality of life of women with BV. Moreover, it has been observed that antiseptic dequalinium chloride (DQC) efficiently reduces symptoms and improves quality of life of the patients during episodes of BV.What the implications are of these findings for clinical practice and/or further research? In the context of the World Health Organisation recommendations on the rational use of antibiotics, we believe that the use of DQC may be a good alternative to antibiotics as a therapy for BV.

The potential value of dequalinium chloride in the treatment of cancer: Focus on malignant glioma.

Dequalinium chloride has been known as one kind of antibiotic that displays a broad antimicrobial spectrum and has been clinically proven to be very safe. In recent years, studies have shown that dequalinium chloride can inhibit the growth of malignant tumours, and reports were mainly used for solid tumours. Glioblastoma is the most common malignant neuroepithelial tumour of the central nervous system in adults, and the prognosis of glioblastoma is poor as it has a high resistance to apoptosis. This review summarizes the current understanding of dequalinium chloride-induced cancer cell apoptosis and its potential role in glioblastoma resistance and progression. Particularly, we focus on dequalinium chloride as it exerts a wide range of anti-cancer activity through its ability to target and accumulate in the mitochondria, and it effectively inhibits the growth of glioblastoma cells in vitro and vivo. Dequalinium chloride is an inhibitor of XIAP and can also act as a mitochondrial targeting agent, which gives it an interesting perspective regarding recent advances in the treatment of malignant glioma.

Vaginal tablets of dequalinium chloride 10 mg versus clotrimazole 100 mg for vaginal candidiasis: a double-blind, randomized study.

PURPOSE: To compare the clinical response, microscopic examination and fungal culture between dequalinium chloride (DQC) and clotrimazole (CT) for treating vaginal candidiasis (VC). METHODS: The double-blind, randomized study was conducted from September 2014 to September 2016 at Siriraj Hospital, Thailand. Eligible participants were Thai women diagnosed with VC by microscopic examination. The exclusion criteria included immunocompromised conditions, consumption of antifungal drugs, and having recurrent VC. Each participant was randomized with a 1:1 allocation to receive six vaginal tablets of 100 mg CT or 10 mg DQC. Two visits included 10 ± 2 days (C1) and 38 ± 4 days (C2). Outcome measures were improvement of VC symptoms, microscopic examination, culture, satisfaction and tolerability. RESULTS: Of 155 eligible participants, 150 were randomized and allocated into CT (N = 76) and DQC (N = 74). The average age was 31.1 ± 7.2 years. Comparable improvement of clinical response was demonstrated (OR at C1 0.79, 95% CI 0.56-1.10, p = 0.197; and OR at C2 0.99, 95% CI 0.69-1.43, p = 0.985). Of CT and DQC groups, the microscopic examination was positive at 11/75 (14.9%) vs 18/72 (25.3%) at C1 and 18/74 (24.3%) vs 28/66 (42.4%) at C2. And the culture was positive at 25/75 (33.8%) vs 46/72 (65.7%) at C1 and at 26/74 (36.6%) vs 46/66 (69.7%) at C2. Most participants had high satisfaction and tolerability and none reported any side effects. CONCLUSION: DQC and CT show comparable clinical response but CT results in greater improvement of microscopic examination and fungal culture. CLINICAL TRIAL REGISTRATION: The Clinical Trial Registry number was NCT02242695. (September 17, 2014).

Dequalinium chloride inhibits the growth of human glioma cells in vitro and vivo: a study on molecular mechanism and potential targeted agents.

BACKGROUND: Our current understanding of the role of dequalinium chloride (DECA) in the progression of glioma remains very limited. This study was aimed to investigate the effect of DECA on human glioma cell lines in vitro and vivo. METHODS: The underlying molecular mechanism was analyzed for developing potential targeted agents. MTT assay, genomic DNA electrophoresis, DAPI staining, TUNEL staining, and wound scratch assay were performed to evaluate the effect of DECA on human glioma cell lines. Bioinformatics methods were used to screen the possible signaling pathway proteins, and the expression of these proteins and the corresponding mRNA was measured. RESULTS: DECA significantly inhibited the growth and proliferation of human glioma cells. Screening of apoptosis-related proteins showed the mRNA expression level of 6 genes was significantly changed after DECA administration. CONCLUSION: This study shows that DECA effectively inhibits the growth of glioma cells in vitro and vivo. DECA may promote glioma cell apoptosis by affecting the expression of NFKB2, HRAS, NF1, CBL, RAF1, and BCL-2 genes.

Repositioning Dequalinium as Potent Muscarinic Allosteric Ligand by Combining Virtual Screening Campaigns and Experimental Binding Assays.

Structure-based virtual screening is a truly productive repurposing approach provided that reliable target structures are available. Recent progresses in the structural resolution of the G-Protein Coupled Receptors (GPCRs) render these targets amenable for structure-based repurposing studies. Hence, the present study describes structure-based virtual screening campaigns with a view to repurposing known drugs as potential allosteric (and/or orthosteric) ligands for the hM2 muscarinic subtype which was indeed resolved in complex with an allosteric modulator thus allowing a precise identification of this binding cavity. First, a docking protocol was developed and optimized based on binding space concept and enrichment factor optimization algorithm (EFO) consensus approach by using a purposely collected database including known allosteric modulators. The so-developed consensus models were then utilized to virtually screen the DrugBank database. Based on the computational results, six promising molecules were selected and experimentally tested and four of them revealed interesting affinity data; in particular, dequalinium showed a very impressive allosteric modulation for hM2. Based on these results, a second campaign was focused on bis-cationic derivatives and allowed the identification of other two relevant hM2 ligands. Overall, the study enhances the understanding of the factors governing the hM2 allosteric modulation emphasizing the key role of ligand flexibility as well as of arrangement and delocalization of the positively charged moieties.

ROS as a novel indicator to predict anticancer drug efficacy.

BACKGROUND: Mitochondria are considered a primary intracellular site of reactive oxygen species (ROS) generation. Generally, cancer cells with mitochondrial genetic abnormalities (copy number change and mutations) have escalated ROS levels compared to normal cells. Since high levels of ROS can trigger apoptosis, treating cancer cells with low doses of mitochondria-targeting / ROS-stimulating agents may offer cancer-specific therapy. This study aimed to investigate how baseline ROS levels might influence cancer cells' response to ROS-stimulating therapy. METHODS: Four cancer and one normal cell lines were treated with a conventional drug (cisplatin) and a mitochondria-targeting agent (dequalinium chloride hydrate) separately and jointly. Cell viability was assessed and drug combination synergisms were indicated by the combination index (CI). Mitochondrial DNA copy number (mtDNAcn), ROS and mitochondrial membrane potential (MMP) were measured, and the relative expression levels of the genes and proteins involved in ROS-mediated apoptosis pathways were also investigated. RESULTS: Our data showed a correlation between the baseline ROS level, mtDNAcn and drug sensitivity in the tested cells. Synergistic effect of both drugs was also observed with ROS being the key contributor in cell death. CONCLUSIONS: Our findings suggest that mitochondria-targeting therapy could be more effective compared to conventional treatments. In addition, cancer cells with low levels of ROS may be more sensitive to the treatment, while cells with high levels of ROS may be more resistant. Doubtlessly, further studies employing a wider range of cell lines and in vivo experiments are needed to validate our results. However, this study provides an insight into understanding the influence of intracellular ROS on drug sensitivity, and may lead to the development of new therapeutic strategies to improve efficacy of anticancer therapy.

Improvement of abnormal vaginal flora in Ugandan women by self-testing and short use of intravaginal antimicrobials.

The vaginal composition of African women is more often lactobacillus-deficient compared to that of women from other areas around the world. Lactobacillus-deficient microflora is a known risk factor for serious health problems, such as preterm birth, cervix cancer, and entrapment of human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs). The aim of this study was to assess the effect of local vaginal antibiotic or antiseptic treatment on abnormal vaginal flora (AVF), aerobic vaginitis (AV), and bacterial vaginosis (BV) among women in rural, semi-urban, and urban areas in Uganda, as compared to placebo. In a double-blind, placebo-controlled, randomized trial, 300 women presenting for outpatient routine, follow-up, or medical care at Mulago Hospital in Kampala, Uganda, were enrolled to receive 6 days of treatment with vaginal rifaximin (RFX), dequalinium chloride (DQC), or placebo if they had an increased vaginal pH of >4.5 as determined by self-testing. At initial visit and at control visit after 4 weeks, a smear was taken for blinded wet mount microscopy to determine AVF, BV, AV, and Candida severity scores. As compared to placebo, both RFX or DQC treatments dramatically diminished BV prevalence and severity from the initial to follow-up visit: the BV score declined from 2.5 to 1.6 (p < 0.0001) and from 2.5 to 1.9 (p < 0.0001), respectively. Similarly, strong improvements in the AV score were seen in both treatment regimens: moderate and severe AV declined from AV scores of 6.3 to 3.6 (p = 0.003) and from 6.6 to 4.1 (p < 0.004), respectively. Also, women with AVF (deceased or absent lactobacilli) showed similar improvements when compared with placebo. Women with normal flora and Candida at the initial visit showed less Candida after 4 weeks in the group treated with DQC (p = 0.014). Even after a short duration of intravaginal treatment with local non-absorbable antiseptics or antibiotics produced significant, lasting improvements in the vaginal microbiome composition of women with disturbed vaginal microflora. As African women have high prevalences of BV, AV, and AVF, this approach could improve their odds to prevent health-compromising complications. Further studies assessing direct health outcomes are needed to substantiate this.

Pharmacologic rescue of an enzyme-trafficking defect in primary hyperoxaluria 1.

Primary hyperoxaluria 1 (PH1; Online Mendelian Inheritance in Man no. 259900), a typically lethal biochemical disorder, may be caused by the AGT(P11LG170R) allele in which the alanine:glyoxylate aminotransferase (AGT) enzyme is mistargeted from peroxisomes to mitochondria. AGT contains a C-terminal peroxisomal targeting sequence, but mutations generate an N-terminal mitochondrial targeting sequence that directs AGT from peroxisomes to mitochondria. Although AGT(P11LG170R) is functional, the enzyme must be in the peroxisome to detoxify glyoxylate by conversion to alanine; in disease, amassed glyoxylate in the peroxisome is transported to the cytosol and converted to oxalate by lactate dehydrogenase, leading to kidney failure. From a chemical genetic screen, we have identified small molecules that inhibit mitochondrial protein import. We tested whether one promising candidate, Food and Drug Administration (FDA)-approved dequalinium chloride (DECA), could restore proper peroxisomal trafficking of AGT(P11LG170R). Indeed, treatment with DECA inhibited AGT(P11LG170R) translocation into mitochondria and subsequently restored trafficking to peroxisomes. Previous studies have suggested that a mitochondrial uncoupler might work in a similar manner. Although the uncoupler carbonyl cyanide m-chlorophenyl hydrazone inhibited AGT(P11LG170R) import into mitochondria, AGT(P11LG170R) aggregated in the cytosol, and cells subsequently died. In a cellular model system that recapitulated oxalate accumulation, exposure to DECA reduced oxalate accumulation, similar to pyridoxine treatment that works in a small subset of PH1 patients. Moreover, treatment with both DECA and pyridoxine was additive in reducing oxalate levels. Thus, repurposing the FDA-approved DECA may be a pharmacologic strategy to treat PH1 patients with mutations in AGT because an additional 75 missense mutations in AGT may also result in mistrafficking.

Use of locally delivered dequalinium chloride in the treatment of vaginal infections: a review.

BACKGROUND: Vaginal infections are responsible for a large proportion of gynaecological outpatient visits. Those are bacterial vaginosis (BV), vulvovaginal candidosis (VVC), aerobic vaginitis (AV) associated with aerobic bacteria, and mixed infections. Usual treatments show similar acceptable short-term efficacy, but frequent recurrences and increasing microbial resistance are unsolved issues. Furthermore, vaginal infections are associated with a variety of serious adverse outcomes in pregnancy and generally have a major impact on quality of life. Identifying the correct therapy can be challenging for the clinician, particularly in mixed infections. FINDINGS: Dequalinium chloride (DQC) is an anti-microbial antiseptic agent with a broad bactericidal and fungicidal activity. Systemic absorption after vaginal application of DQC is very low and systemic effects negligible. Vaginal DQC (Fluomizin vaginal tablets) has been shown to have equal clinical efficacy as clindamycin in the treatment of BV. Its broad antimicrobial activity makes it appropriate for the treatment of mixed vaginal infections and in case of uncertain diagnosis. Moreover, resistance of pathogens is unlikely due to its multiple mode of action, and vaginal DQC provides also a reduced risk for post-treatment vaginal infections. CONCLUSIONS: Vaginal DQC (10 mg) as 6-day therapy offers a safe and effective option for empiric therapy of different vaginal infections in daily practice. This review summarizes the available and relevant pharmacological and clinical data for the therapy of vaginal infections with vaginal DQC and provides the rationale for its use in daily gynaecologic practice.

Mechanisms of resistance to apoptosis in the human acute promyelocytic leukemia cell line NB4.

Current frontline therapies have improved overall survival in acute promyelocytic leukemia (APL) patients to exceptional rates; however, relapse is still a problem among high-risk and old patients. Therefore, the development of better and safer therapies continues to be a goal in the treatment of this disease. In the present work, we examined three different pathways that hinder cell death in the APL cell line NB4, shedding light on the mechanisms that underlie resistance to apoptosis in these cells and that might help provide them with a proliferative advantage. We found that the proteasome inhibitor MG-132 specifically induces in NB4 cells an Nrf2-mediated antioxidant response which counteracts mitochondria-dependent apoptosis induced by the lipophilic cation dequalinium. More importantly, we also demonstrated that high basal autophagy levels and the gain-of-function of mutant p53 are intrinsic mechanisms of resistance to apoptosis in this cell line. According to our results, the pharmacological inhibition of autophagy and p53 mutants are useful tools to explore resistance to apoptosis in APL and other types of cancer and could be the bases of new therapeutic approaches that improve the efficiency and allow dose reduction of the current treatments.

Design and development of novel mitochondrial targeted nanocarriers, DQAsomes for curcumin inhalation.

Curcumin has potent antioxidant and anti-inflammatory properties but poor absorption following oral administration owing to its low aqueous solubility. Development of novel formulations to improve its in vivo efficacy is therefore challenging. In this study, formulation of curcumin-loaded DQAsomes (vesicles formed from the amphiphile, dequalinium) for pulmonary delivery is presented for the first time. The vesicles demonstrated mean hydrodynamic diameters between 170 and 200 nm, with a ζ potential of approximately +50 mV, high drug loading (up to 61%) and encapsulation efficiency (90%), resulting in enhanced curcumin aqueous solubility. Curcumin encapsulation in DQAsomes in the amorphous state was confirmed by X-ray diffraction and differential scanning calorimetry analysis. The existence of hydrogen bonds and cation-π interaction between curcumin and vesicle building blocks, namely dequalinium molecules, were shown in lyophilized DQAsomes using FT-IR analysis. Encapsulation of curcumin in DQAsomes enhanced the antioxidant activity of curcumin compared to free curcumin. DQAsome dispersion was successfully nebulized with the majority of the delivered dose deposited in the second stage of the twin-stage impinger. The vesicles showed potential for mitochondrial targeting. Curcumin-loaded DQAsomes thus represent a promising inhalation formulation with improved stability characteristics and mitochondrial targeting ability, indicating a novel approach for efficient curcumin delivery for effective treatment of acute lung injury and the rationale for future in vivo studies.

[Changes in mitochondrial function induced by dequalinium precede oxidative stress and apoptosis in the human prostate cancer cell line PC-3].

Mitochondria play central roles in diverse physiological and pathological conditions associated with cell survival and death. Delocalized lipophilic cations, such as dequalinium (DQA), are accumulated in cancer cells attracted by the highly negative mitochondrial transmembrane potential of these cells. DQA showed a potent anticancer activity in cells from different malignancies. Here, we report the effect of DQA on PC-3 prostate cancer cells. Incubation with DQA at concentrations between 1.5 and 100 microM from 24 to 48 h decreases cell viability. The decrease in cell viability together with a loss of mitochondrial transmembrane potential induced an increase in reactive oxygen species production and cell death via caspase-3 dependent apoptotic pathway. QA was shown to cause moderate to strong cell death in a time and concentration dependent manner, causing a most advantageous effect at a concentration of 10 microM applied for a long 48 h time period, which might be a consequence of the kinetics of intracellular DQA accumulation in mitochondria, but also of the mechanisms of DQA-induced cell death. This data shows DQA as a promising agent against the human prostate cancer PC-3 cell line, activating the caspase-3 dependent apoptotic pathway. This fact might be beneficial for possible future applications in cancer therapy.

Efficacy of Dequalinium Chloride vs Metronidazole for the Treatment of Bacterial Vaginosis: A Randomized Clinical Trial.

Importance: Bacterial vaginosis (BV) is a common cause of vaginal infection. First-line treatments of BV are metronidazole and clindamycin. Due to the increase in antibiotic resistance, effective nonantibiotic treatments for BV are needed. Objective: To examine whether dequalinium chloride, a broad-spectrum antiseptic, is noninferior to oral metronidazole for the treatment of BV. Design, Setting, and Participants: This phase 4, multicenter, triple-blind, double-dummy, parallel, noninferiority randomized clinical trial was conducted from July 29, 2021, to August 25, 2022, with a 1-month follow-up. Participants were premenopausal women 18 years or older with BV from 11 gynecologic practices and 1 hospital in Poland, Slovakia, and the Czech. Intervention: Patients were randomized to treatment with dequalinium chloride vaginal tablets (10 mg once daily for 6 days) or oral metronidazole (500 mg twice daily for 7 days). Double-dummy medication kits contained vaginal and oral tablets with placebo and active medication. Main Outcomes and Measures: The main outcome was the noninferiority margin (of 15 percentage points) in the absolute difference in clinical cure rates between dequalinium chloride and metronidazole 7 to 11 days after start of treatment (visit 1). Noninferiority was met if the lower 95% CI for the difference in clinical cure rate was less than 15 percentage points at visit 1. Results: A total of 147 women (mean [SD] age, 36.7 [9.0] years) were treated with dequalinium chloride (n = 72) or metronidazole (n = 75). The clinical cure rates at visit 1 were 64 of 69 (92.8%) for dequalinium chloride vs 69 of 74 (93.2%) for metronidazole in the intention-to-treat population, whereas in the per-protocol population, cure rates were 54 of 58 (93.1%) for dequalinium chloride vs 48 of 53 (90.6%) for metronidazole. The treatment differences of -0.5 percentage points (95% CI, -10.8 to 9.8 percentage points; P = .002) in the intention-to-treat population and 2.5 percentage points (95% CI, -9.4 to 14.4 percentage points; P = .001) in the per-protocol population confirmed the noninferiority of dequalinium chloride. The tolerability of dequalinium chloride was rated as very good by 30 of 50 patients (60.0%) but only by 21 of 54 (38.9%) for metronidazole. Three patients in the metronidazole group suspended treatment due to an adverse event. Conclusions and Relevance: This randomized clinical trial showed that dequalinium chloride was not inferior to metronidazole for the treatment of BV. Dequalinium chloride had a similarly high cure rate but with better tolerability and fewer adverse events. With a similar efficacy to metronidazole and clindamycin, dequalinium chloride warrants consideration as first-line treatment for BV to help reduce antibiotic consumption. Trial Registration: EudraCT: 2020-002489-15.

Towards boron neutron capture therapy: the formulation and preliminary in vitro evaluation of liposomal vehicles for the therapeutic delivery of the dequalinium salt of bis-nido-carborane.

Liposomes of phosphatidylcholine or of dimyristoylphosphatidylcholine that incorporate bis-nido-carborane dequalinium salt are stable in physiologically relevant media and have in vitro toxicity profiles that appear to be compatible with potential therapeutic applications. These features render the structures suitable candidate boron-delivery vehicles for evaluation in the boron neutron capture therapy of cancer.

Tackling antibiotic resistance by inducing transient and robust collateral sensitivity.

Collateral sensitivity (CS) is an evolutionary trade-off traditionally linked to the mutational acquisition of antibiotic resistance (AR). However, AR can be temporally induced, and the possibility that this causes transient, non-inherited CS, has not been addressed. Mutational acquisition of ciprofloxacin resistance leads to robust CS to tobramycin in pre-existing antibiotic-resistant mutants of Pseudomonas aeruginosa. Further, the strength of this phenotype is higher when nfxB mutants, over-producing the efflux pump MexCD-OprJ, are selected. Here, we induce transient nfxB-mediated ciprofloxacin resistance by using the antiseptic dequalinium chloride. Notably, non-inherited induction of AR renders transient tobramycin CS in the analyzed antibiotic-resistant mutants and clinical isolates, including tobramycin-resistant isolates. Further, by combining tobramycin with dequalinium chloride we drive these strains to extinction. Our results support that transient CS could allow the design of new evolutionary strategies to tackle antibiotic-resistant infections, avoiding the acquisition of AR mutations on which inherited CS depends.

N-palmitoyl-ethanolamine (PEA) induces peripheral antinociceptive effect by ATP-sensitive K+-channel activation.

Although the antinociceptive effects of N-palmitoyl-ethanolamine (PEA) were first characterized nearly 50 years ago, the identity of the mechanism that mediates these actions has not been elucidated. The present study investigated the contribution of K(+) channels on peripheral antinociception induced by the CB(2) agonist PEA. Nociceptive thresholds to mechanical paw stimulation of Wistar rats treated with intraplantar prostaglandin E(2) to induce hyperalgesia were measured, and other agents were also given by local injection. PEA (5, 10, and 20 µg/paw) elicited a local peripheral antinociceptive effect. This effect was antagonized by glibenclamide, a selective blocker of ATP-sensitive K(+) channels (20, 40, and 80 µg/paw). In addition, neither the voltage-dependent K(+) channel-specific blocker tetraethylammonium (30 µg/paw) nor the small and large conductance blockers of Ca(2+)-activated K(+) channels, dequalinium (50 µg/paw) and paxilline (20 µg/paw), respectively, were able to block the local antinociceptive effect of PEA. These results indicate that the activation of ATP-sensitive K(+) channels could be the mechanism that induces peripheral antinociception by PEA and that voltage-dependent K(+) channels and small and large conductance Ca(2+)-activated K(+) channels do not appear to be involved in this mechanism.