RESUMO
There is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and mundulone acetate (MA) as inhibitors of in vitro intracellular Ca2+-regulated myometrial contractility. In this study, we probed the tocolytic potential of these compounds using human myometrial samples and a mouse model of preterm birth. In a phenotypic assay, mundulone displayed greater efficacy, while MA showed greater potency and uterine-selectivity in the inhibition of intracellular-Ca2+ mobilization. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted inhibition of myometrial contractions and that neither compounds affected vasoreactivity of ductus arteriosus. A high-throughput combination screen identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these combinations, mundulone+atosiban demonstrated a significant improvement in the in vitro therapeutic index compared to mundulone alone. The ex vivo and in vivo synergism of mundulone+atosiban was substantiated, yielding greater tocolytic efficacy and potency on myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone after mifepristone administration dose-dependently delayed the timing of delivery. Importantly, mundulone+atosiban permitted long-term management of PL, allowing 71% dams to deliver viable pups at term (>day 19, 4-5 days post-mifepristone exposure) without visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the development of mundulone as a single or combination tocolytic for management of PL.
Assuntos
Produtos Biológicos , Trabalho de Parto Prematuro , Nascimento Prematuro , Tocolíticos , Feminino , Recém-Nascido , Camundongos , Animais , Humanos , Tocolíticos/farmacologia , Tocolíticos/uso terapêutico , Nascimento Prematuro/tratamento farmacológico , Nifedipino/farmacologia , Nifedipino/uso terapêutico , Mifepristona/uso terapêutico , Produtos Biológicos/uso terapêutico , Trabalho de Parto Prematuro/tratamento farmacológicoRESUMO
Currently, there is a lack of FDA-approved tocolytics for the management of preterm labor (PL). In prior drug discovery efforts, we identified mundulone and its analog mundulone acetate (MA) as inhibitors of in vitro intracellular Ca 2+ -regulated myometrial contractility. In this study, we probed the tocolytic and therapeutic potential of these small molecules using myometrial cells and tissues obtained from patients receiving cesarean deliveries, as well as a mouse model of PL resulting in preterm birth. In a phenotypic assay, mundulone displayed greater efficacy in the inhibition of intracellular-Ca 2+ from myometrial cells; however, MA showed greater potency and uterine-selectivity, based IC 50 and E max values between myometrial cells compared to aorta vascular smooth muscle cells, a major maternal off-target site of current tocolytics. Cell viability assays revealed that MA was significantly less cytotoxic. Organ bath and vessel myography studies showed that only mundulone exerted concentration-dependent inhibition of ex vivo myometrial contractions and that neither mundulone or MA affected vasoreactivity of ductus arteriosus, a major fetal off-target of current tocolytics. A high-throughput combination screen of in vitro intracellular Ca 2+ -mobilization identified that mundulone exhibits synergism with two clinical-tocolytics (atosiban and nifedipine), and MA displayed synergistic efficacy with nifedipine. Of these synergistic combinations, mundulone + atosiban demonstrated a favorable in vitro therapeutic index (TI)=10, a substantial improvement compared to TI=0.8 for mundulone alone. The ex vivo and in vivo synergism of mundulone and atosiban was substantiated, yielding greater tocolytic efficacy and potency on isolated mouse and human myometrial tissue and reduced preterm birth rates in a mouse model of PL compared to each single agent. Treatment with mundulone 5hrs after mifepristone administration (and PL induction) dose-dependently delayed the timing of delivery. Importantly, mundulone in combination with atosiban (FR 3.7:1, 6.5mg/kg + 1.75mg/kg) permitted long-term management of PL after induction with 30 µg mifepristone, allowing 71% dams to deliver viable pups at term (> day 19, 4-5 days post-mifepristone exposure) without any visible maternal and fetal consequences. Collectively, these studies provide a strong foundation for the future development of mundulone as a stand-alone single- and/or combination-tocolytic therapy for management of PL.
RESUMO
Type 2 diabetes mellitus (T2DM) accompanied by hyperlipidemia confers higher risk for diabetes as well as cardiovascular diseases. NF-κB is actively involved in generating low-grade inflammation and oxidative stress triggering the development of diabetic complications. In this study, we have attempted to investigate the association between NF-κB1 functional promoter polymorphism-94 ATTG insertion/deletion (rs28362491) with inflammatory markers in developing diabetes-linked dyslipidemia. We performed a case-control study in a total of 401 individuals belonging to three categories such as Type 2 diabetes with dyslipidemia, Type 2 diabetes without dyslipidemia, and normal healthy controls. Experiments were carried out using genotyping, real-time PCR, and western blot. Pearson's correlation, analysis of variance, and logistic regression were utilized for statistical analysis. As per genetic association conducted in this study the SNP rs28362491 showed significant allelic and genotypic associations (Allelic: OR = 1.374, CI 0.9797-1.927, p = 0.003, and Genotypic in dominant model: OR = 1.77, CI 1.04-2.99, p = 0.002) with the risk of diabetes and associated dyslipidemia. The -94 ATTG insertion/insertion (ins/ins) genotype was associated with significantly increased level of serum TNF-α (p = 0.002), serum IL-6 (p = 0.067) in diabetes-induced dyslipidemia. Multiple linear regression analysis identifies independent correlation of Total cholesterol, HDL, LDL, TNF-α, and rs28362491 ATTG ins/ins with triglyceride in diabetic dyslipidemic condition. T2DM with dyslipidemia having ins/ins genotype showed significant increased expression of pro-inflammatory cytokines such as TNF-α, IL-6, and activation of NF-κB. Our study reports that individuals with ATTG insertion allele and ATTG ins/ins genotype at NF-κB1 promoter regulatory gene predicts the risk and severity of T2DM-linked dyslipidemia.