Inhaled drug delivery: Mechanisms by which pressurised metered dose inhaler excipients affect respiratory membrane biophysics.

吸入药物输送：加压定量吸入器赋形剂影响呼吸膜生物物理学的机制。

• 批准号: 1764834
• 金额: --
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1764834
• 关键词: Inhaled; drug; delivery; Mechanisms; pressurised

Strategi Research Priority: Bioscience for HealthBackground: Glycerol was added to some products as a non-volatile component to modify aerosol particle size when pressurised metered dose inhalers were reformulated with hydrofluoroalkanes in the 1990's to comply with the Montreal treaty on greenhouse gases. It was recently discovered that the addition of glycerol to inhaler formulations to increase aerosol particle size may affect drug bioavailability even when pharmaceutical aerosols are aerodynamically equivalent. Previous studies comparing glycerol free and glycerol containing formulations have observed differences in the pharmaceutical properties and performances of these formulations. It is hypothesized that the effects of glycerol on the disposition of deposited drug goes beyond changes in particle size. Not only may glycerol have effects on the release of drug from the aerosol particle, it might also play a role in transiently modifying the permeability of the lung cell membranes. The aim of this study is to gain more insight into the effect glycerol present in inhaled drug particles would have on the permeability of the airway epithelium. These effects will be studied in vitro using the Calu-3 cell continuous cell line. Specific objectives include evaluation of Calu-3 cells tolerability to glycerol. The outcome of the tolerability studies will be used to establish a concentration range for further investigations into the effect of glycerol on the permeability of cell layers using transport markers in vitro.Method: The MTT assay was used to evaluate the toxicity of glycerol to the cells and to determine an LC50 value. Glycerol concentrations ranged between 1% to 35% v/v. The effect of glycerol on the cell layer integrity was investigated via trans-epithelial electrical resistance (TEER) measurements. Cell layer permeability of two transport markers; 3H-digoxin and 14C-Mannitol (transcellular and paracellular transport markers respectively) was also assessed. The glycerol concentrations chosen for the permeability studies were such that gave cell viability between 60% and 100% as reported by the MTT studies.Results: LC50 value was determined by to be 14% v/v. TEER values showed that the tight junctions were perturbed with increasing glycerol concentration and upon prolonged glycerol exposure. Permeability across cell layers for both markers was also enhanced by glycerol (24-fold for mannitol and 6-fold for digoxin). This was expected for mannitol especially because the tight junctions which constitute the paracellular route had been compromised.Conclusion: The LC50 of glycerol with Calu-3 cells was determined and the range of concentrations used in the toxicity assay showed the extent of tolerability of the cell line to glycerol. Glycerol also appeared to enhance the permeability of cell monolayers to transport markers. Further studies are required to establish optimum conditions for the investigation of BDP transport and whether this observed glycerol effect on membrane permeability translates to effects on drug transport in lung tissue.

战略研究优先级：健康生物科学背景：在20世纪90年代，为了遵守蒙特利尔温室气体条约，当加压计量吸入器用氢氟烷烃重新配制时，甘油作为非挥发性组分被添加到一些产品中以改变气溶胶颗粒尺寸。最近发现，即使当药用气雾剂在气动力学上等效时，向吸入器制剂中添加甘油以增加气雾剂粒度也可能影响药物生物利用度。先前比较无甘油和含甘油制剂的研究已经观察到这些制剂的药物性质和性能的差异。据推测，甘油对沉积药物处置的影响超出了粒度变化。甘油不仅可以影响药物从气溶胶颗粒中的释放，它还可以在瞬时改变肺细胞膜的渗透性方面发挥作用。本研究的目的是更深入地了解吸入药物颗粒中存在的甘油对气道上皮细胞渗透性的影响。将使用Calu-3细胞连续细胞系在体外研究这些效应。具体目标包括评价Calu-3细胞对甘油的耐受性。的耐受性研究的结果将被用来建立一个浓度范围，用于进一步调查甘油对细胞层的渗透性使用运输markers in vitro.Method的影响：MTT法被用来评估甘油的毒性细胞，并确定LC 50值。甘油浓度范围为1%至35%v/v。甘油对细胞层完整性的影响通过跨上皮电阻（TEER）测量进行了研究。还评估了两种转运标记物的细胞层渗透性; 3 H-地高辛和14 C-甘露糖醇（分别为跨细胞和细胞旁转运标记物）。选择的渗透性研究的甘油浓度是这样的，给细胞活力在60%和100%之间的MTT study.Results报告：LC 50值确定为14%v/v。TEER值表明，随着甘油浓度的增加，并在长期甘油暴露的紧密连接被扰乱。两种标记物跨细胞层的渗透性也被甘油增强（甘露醇为24倍，地高辛为6倍）。这是预期甘露醇，特别是因为紧密连接，构成的paracellular route已compromised.Conclusion：的LC 50的甘油与Calu-3细胞的测定和毒性试验中使用的浓度范围显示的耐受性的细胞系甘油的程度。甘油似乎也能增强细胞单层对转运标记物的渗透性。需要进一步研究以确定研究BDP转运的最佳条件，以及观察到的甘油对膜通透性的影响是否转化为对肺组织中药物转运的影响。