Kashyap Mahendra, Pore Subrata, Yoshimura Naoki, Tyagi Pradeep
Department of Urology, University of Pittsburgh, Pittsburgh, United States.
Department of Urology, University of Pittsburgh, Pittsburgh, United States.
Life Sci. 2016 Mar 1;148:93-8. doi: 10.1016/j.lfs.2016.02.009. Epub 2016 Feb 5.
It is known that bladder exposure to noxious stimuli elicits nerve growth factor (NGF) expression with region wise differences. Here, we investigated the effect of bladder distension (cystometry) and bladder wall injection of NGF antisense oligonucleotide (ODN) together as well as separately on spontaneous (constitutive) expression of NGF and its cognate p75 neurotrophin receptor (p75(NTR)).
Under isoflurane anesthesia, either 15μg of protamine sulfate (vehicle) alone or complexed with 1.5μg of NGF antisense or scrambled ODN was injected (10μL) at 4 sites in bladder wall of 24 adult female Sprague-Dawley rats and 6 rats were left untreated (n=30). Under urethane anesthesia, cystometry (CMG) was performed in treated and control rats. Fluorescent ODN and NGF/p75(NTR) expression was localized in harvested tissue.
Complexation of ODN with protamine was essential for the retention of ODN in bladder tissue as the uncomplexed ODN was untraceable after injection. Bladder distension from CMG raised the expression of NGF and p75(NTR) relative to CMG naïve rats. The groups treated with vehicle, scrambled and antisense ODN were indistinct with regard to CMG parameters, but the intense immunoreactivity of NGF and p75(NTR) seen in the vehicle and scrambled ODN groups was reduced following treatment with NGF antisense.
The constitutive expression of NGF and p75(NTR) is responsive to bladder distension and administration of NGF antisense. Complexation with protamine reduces the clearance of ODN and demonstrates the potential of ODN nanoparticles as an option for reducing the inducible NGF expression in OAB patients following intradetrusor injection.
已知膀胱暴露于有害刺激会引发神经生长因子（NGF）表达，且存在区域差异。在此，我们研究了膀胱扩张（膀胱测压）以及膀胱壁单独或联合注射NGF反义寡核苷酸（ODN）对NGF及其同源p75神经营养因子受体（p75(NTR)）的自发（组成性）表达的影响。
在异氟烷麻醉下，将15μg硫酸鱼精蛋白（载体）单独或与1.5μg NGF反义或乱序ODN复合后，在24只成年雌性Sprague-Dawley大鼠的膀胱壁4个部位注射（10μL），6只大鼠未接受治疗（n = 30）。在氨基甲酸乙酯麻醉下，对治疗组和对照组大鼠进行膀胱测压（CMG）。荧光ODN以及NGF/p75(NTR)表达定位于收获的组织中。
ODN与鱼精蛋白复合对于ODN保留在膀胱组织中至关重要，因为注射后未复合的ODN无法追踪。与未进行CMG的大鼠相比，CMG引起的膀胱扩张提高了NGF和p75(NTR)的表达。载体、乱序和反义ODN处理组在CMG参数方面无明显差异，但在用NGF反义处理后，载体组和乱序ODN组中观察到的NGF和p75(NTR)强烈免疫反应性降低。
NGF和p75(NTR)的组成性表达对膀胱扩张和NGF反义给药有反应。与鱼精蛋白复合可降低ODN的清除率，并证明ODN纳米颗粒作为降低膀胱逼尿肌内注射后OAB患者诱导性NGF表达的一种选择的潜力。
