Targeting of LOS for Treatment of Antibiotic-Resistant Neisseria gonorrhoeae

LOS 靶向治疗抗生素耐药性淋病奈瑟菌

• 批准号: 10617635
• 负责人: Gary A Jarvis
• 金额: --
• 依托单位: VETERANS AFFAIRS MED CTR SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10617635
• 关键词: Amino Acids; Anabolism; Anti-Bacterial Agents; Antibiotic Therapy; Antibiotics; Antimicrobial Cationic Peptides; Azithromycin; Bacteria; Binding Proteins; Biological Assay; Canada; Cardiovascular system; Cefixime; Ceftriaxone; Cells; Cephalosporins; Cervical; Classification; Clinical; Complement; Country; Cytolysis; DNA Binding; Data; Denmark; Drug Kinetics; Drug-resistant Neisseria Gonorrhoeae; Ectopic Pregnancy; Environment; Enzymes; Epithelial Cells; Evaluation; Exposure to; Female; Generations; Gonorrhea; Gram-Negative Bacteria; HIV; Healthcare; Healthcare Systems; Hemolysis; Human; Immune response; In Vitro; Incidence; Infection; Infertility; Inflammation; Inflammatory; Innate Immune System; Invaded; Investigation; Japan; Lipid A; Measurable; Mediating; Membrane; Military Personnel; Mission; Modeling; Morbidity - disease rate; Multi-Drug Resistance; Neisseria gonorrhoeae; Outcome; Patient Care; Pelvic Inflammatory Disease; Penetration; Peptides; Permeability; Predisposition; Proteolysis; Public Health; Recommendation; Reporting; Research; Resistance; Resistance development; Risk Behaviors; Sexually Transmitted Diseases; Testing; Therapeutic; Time; Toxic effect; Vaccines; Variant; Veterans; Woman; Work; active duty; antimicrobial; bactericide; chronic pelvic pain; cytokine; cytotoxicity; design; efficacy testing; efflux pump; high risk; in vitro Assay; in vitro testing; in vivo; in vivo evaluation; inhibitor; interest; lead candidate; lipid biosynthesis; lipooligosaccharide; men; military service; mouse model; neutrophil; novel; novel therapeutics; prevent; reproductive tract; resistant strain; transmission process

Infections due to N. gonorrhoeae are a major cause of morbidity with an estimated 850,000 cases in the U.S. and 87 million cases worldwide annually. Within the VA Health Care System, cases of gonorrhea increased between 2013 and 2017 with the total number in that time period at 10,587. The most serious sequelae are suffered by infected women as gonococci ascend to the upper reproductive tract and cause pelvic inflammatory disease in 10-20% of women with infections, which encompasses a wide range of inflammatory conditions and often leads to chronic pelvic pain, infertility, and ectopic pregnancy. There is no vaccine to N. gonorrhoeae and a great need for new antibiotics due to the alarming rise in multidrug-resistance (MDR), which is making emergence of untreatable gonococcal infections a real prospect. Currently only ceftriaxone and azithromycin are recommended for first-line therapy, and clinical isolates resistant to both of those antibiotics have been reported in countries including Denmark, Canada, and Japan. Thus, there is a compelling need for new antimicrobials for gonococcal infections. Our studies to date of N. gonorrhoeae lipooligosaccharide (LOS) and the human innate immune system have shown that the lipid A portion of LOS is the primary inducer of cytokine-mediated inflammation and investigations by others have shown that the lipid A also facilitates gonococcal infection. These data led us to the concept that targeting lipid A biosynthesis would be an effective approach to combating N. gonorrhoeae infections. We recently reported that inhibition of LpxC, the enzyme that catalyzes the second step of lipid A biosynthesis, was bactericidal for nine multidrug-resistant and human challenge strains of gonococci and reduced cytokine induction without apparent human cell cytotoxicity. From the LpxC inhibitor data, we postulated that membrane disruption due to the inhibition of LOS biosynthesis was lethal for gonococci. To investigate this, we recently evaluated the bactericidal potential of a 12 amino acid cell-penetrating peptide (CPP) for MDR and human challenge strains of N. gonorrhoeae and found that the CPP penetrated the bacterial membrane and was bactericidal for all nine MDR and human challenge strains of gonococci tested. Importantly, no apparent resistance to the CPP developed in surviving bacteria as susceptibility was the same in bacteria from colonies after exposure to CPP and then retreated. Further, the CPP reduced inflammatory cytokine induction and prevented bacterial cell invasion of cervical epithelial cells in the absence of measurable cell cytotoxicity. These novel data highlight LpxC and CPP as promising antimicrobials for N. gonorrhoeae and strongly support the hypothesis of this application that inhibiting the biosynthesis of lipid A components with LpxC inhibitors and disrupting outer membrane integrity with CPP will impact bacterial viability and host response to N. gonorrhoeae infection in vitro and in vivo, which will have a therapeutic impact on infection outcomes. This project is focused on optimizing and testing the efficacy of the CPP and LpxC inhibitor in relevant in vitro assays of bactericidal activity, cytokine induction, hemolysis, and cell cytotoxicity. Mechanistic studies will include investigations of DNA binding, cell permeabilization, proteolysis resistance, protein binding and the effect of the MtrCDE, MacAB and NorM gonococcal efflux pumps. The lead candidate CPP and LpxC inhibitor identified in vitro will be tested for in vivo efficacy, pharmacokinetics and cardiovascular toxicity in an established female mouse model of gonococcal genital tract infection that has been increasingly used for evaluation of candidate antimicrobials for treatment of gonorrhea. We expect that the results from our studies will demonstrate the efficacy of these two antimicrobials as new therapeutics for N. gonorrhoeae infection, which are urgently needed given the rise in MDR gonococcal strains. This will be the first study of its kind to test these two classes of antimicrobials for efficacy against gonorrhea.

淋病链球菌引起的感染是发病率的主要原因，估计有850,000例 每年在全球范围内的美国和8700万个案件。在VA医疗保健系统中，淋病病例 在2013年至2017年之间，该时间段的总数为10,587。最严重的 后遗症被感染的妇女遭受淋球菌上升到上部生殖道的痛苦，并导致 10-20％感染的女性中有10-20％的骨盆炎症性疾病，其中包括广泛的 炎症状况，通常会导致慢性骨盆疼痛，不育和异位妊娠。没有 淋病N. （MDR），这使得不可治疗的淋球菌感染的出现成为真正的前景。目前仅 建议将头孢曲松和阿奇霉素用于一线治疗，并且抗两者的临床分离株 这些抗生素已在包括丹麦，加拿大和日本在内的国家报告。因此，有一个 强迫对淋球菌感染的新抗菌剂的需求。 我们的研究迄今为止淋病的脂肪含糖（LOS）和人类先天免疫系统 已经表明，LOS的一部分是细胞因子介导的炎症和 其他人的调查表明，脂质A还促进了淋球菌感染。这些数据导致我们 靶向脂质生物合成的概念将是对抗淋病猪笼草的有效方法 感染。我们最近报道了抑制LPXC，催化脂质A的第二步的酶 生物合成，是淋球菌的九种耐多药和人类挑战菌株的杀菌性 细胞因子诱导降低而没有明显的人类细胞毒性。 从LPXC抑制剂数据中，我们假设由于LOS抑制而导致的膜破坏 生物合成对淋球菌致死。为了调查这一点，我们最近评估了A的杀菌潜力 12氨基酸细胞穿透肽（CPP），用于淋病和淋病的MDR和人类挑战菌株 发现CPP穿透了细菌膜，并且在所有九个MDR和人类中都是杀菌性的 测试的淋球菌的挑战菌株。重要的是，在生存中没有明显的对CPP的抵抗力 暴露于CPP后菌落中的细菌中，细菌作为易感性相同，然后退缩。 此外，CPP降低了炎性细胞因子诱导并防止细菌细胞侵袭宫颈 在没有可测量的细胞细胞毒性的情况下，上皮细胞。 这些新的数据凸显了LPXC和CPP作为淋病猪笼草的有希望的抗菌素 支持该应用的假设，该假设抑制了脂质A成分LPXC的生物合成 抑制剂和用CPP破坏外膜完整性会影响细菌的生存力，并宿主对 在体外和体内感染的淋病链球菌感染将对感染结果产生治疗影响。 该项目的重点是优化和测试CPP和LPXC抑制剂在相关性中的功效 杀菌活性，细胞因子诱导，溶血和细胞毒性的体外测定。机械研究将 包括研究DNA结合，细胞透化，抗蛋白水解性，蛋白质结合和 MTRCDE，MACAB和NORM GONOCOCOCOCOCOCOCOCCAL PUMPS的影响。铅候选CPP和LPXC抑制剂 鉴定在体外的体内功效，药代动力学和心血管毒性的测试 已越来越多地用于淋球菌生殖道感染的雌性小鼠模型 评估候选抗菌药物治疗淋病。 我们预计我们的研究结果将证明这两种抗菌剂的功效是新的 淋病感染的n。 这将是测试这两类抗菌剂对​​淋病的功效的第一个研究。

项目成果

Novel small molecules that increase the susceptibility of Neisseria gonorrhoeae to cationic antimicrobial peptides by inhibiting lipid A phosphoethanolamine transferase.

• DOI: 10.1093/jac/dkac204
• 发表时间: 2022-08-25
• 期刊: JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY
• 影响因子: 5.2
• 作者: Mullally, Christopher;Stubbs, Keith A.;Thai, Van C.;Anandan, Anandhi;Bartley, Stephanie;Scanlon, Martin J.;Jarvis, Gary A.;John, Constance M.;Lim, Katherine Y. L.;Sullivan, Courtney M.;Sarkar-Tyson, Mitali;Vrielink, Alice;Kahler, Charlene M.
• 通讯作者: Kahler, Charlene M.