A comparison of drug transport in pulmonary absorption models: isolated perfused rat lungs, respiratory epithelial cell lines and primary cell culture

Purpose: To evaluate the ability of human airway epithelial cell layers and a simple rat isolated perfused lung (IPL) model to predict pulmonary drug absorption in rats in vivo. Method: The permeability of seven compounds selected to possess a range of lipophilicity was measured in two airway cell lines (Calu-3 and 16HBE14o-), in normal human bronchial epithelial (NHBE) cells and using a simple isolated perfused lungs (IPL) technique. Data from the cell layers and ex vivo lungs were compared to published absorption rates from rat lungs measured in vivo. Results: A strong relationship was observed between the logarithm of the in vivo absorption half-life and the absorption half-life in the IPL (r = 0.97; excluding formoterol). Good log-linear relationships were also found between the apparent first-order absorption rate in vivo and cell layer permeability with correlation coefficients of 0.92, 0.93, 0.91 in Calu-3, 16HBE14o- and NHBE cells, respectively. Conclusion: The simple IPL technique provided a good prediction of drug absorption from the lungs, making it a useful method for empirical screening of drug absorption in the lungs. Permeability measurements were similar in all the respiratory epithelial cell models evaluated, with Calu-3 having the advantage for routine permeability screening purposes of being readily availability, robust and easy to culture

A Cell-based Computational Modeling Approach for Developing Site-Directed Molecular Probes

Modeling the local absorption and retention patterns of membrane-permeant small molecules in a cellular context could facilitate development of site-directed chemical agents for bioimaging or therapeutic applications. Here, we present an integrative approach to this problem, combining in silico computational models, in vitro cell based assays and in vivo biodistribution studies. To target small molecule probes to the epithelial cells of the upper airways, a multiscale computational model of the lung was first used as a screening tool, in silico. Following virtual screening, cell monolayers differentiated on microfabricated pore arrays and multilayer cultures of primary human bronchial epithelial cells differentiated in an air-liquid interface were used to test the local absorption and intracellular retention patterns of selected probes, in vitro. Lastly, experiments involving visualization of bioimaging probe distribution in the lungs after local and systemic administration were used to test the relevance of computational models and cell-based assays, in vivo. The results of in vivo experiments were consistent with the results of in silico simulations, indicating that mitochondrial accumulation of membrane permeant, hydrophilic cations can be used to maximize local exposure and retention, specifically in the upper airways after intratracheal administration

Using the Multidimensional Prognostic Index (MPI) to improve cost-effectiveness of interventions in multimorbid frail older persons: results and final recommendations from the MPI_AGE European Project

MPI_AGE is a European Union co-funded research project aimed to use the Multidimensional Prognostic Index (MPI), a validated Comprehensive Geriatric Assessment (CGA)-based prognostic tool, to develop predictive rules that guide clinical and management decisions in older people in different European countries. A series of international studies performed in different settings have shown that the MPI is useful to predict mortality and risk of hospitalization in community-dwelling older subjects at population level. Furthermore, studies performed in older people who underwent a CGA before admission to a nursing home or receiving homecare services showed that the MPI successfully identified groups of persons who could benefit, in terms of reduced mortality, of specific therapies such as statins in diabetes mellitus and coronary artery disease, anticoagulants in atrial fibrillation and antidementia drugs in cognitive decline. A prospective trial carried out in nine hospitals in Europe and Australia demonstrated that the MPI was able to predict not only in-hospital and long-term mortality, but also institutionalization, re-hospitalization and receiving homecare services during the one-year follow-up after hospital discharge. The project also explored the association between MPI and mortality in hospitalized older patients in need of complex procedures such as transcatheter aortic valve implantation or enteral tube feeding. Evidence from these studies has prompted the MPI_AGE Investigators to formulate recommendations for healthcare providers, policy makers and the general population which may help to improve the cost-effectiveness of appropriate health care interventions for older patients

Enteral tube feeding and mortality in hospitalized older patients: A multicenter longitudinal study

Background & aims: The literature regarding enteral nutrition and mortality in older frail people is limited and still conflicting. Moreover, the potential role of comprehensive geriatric assessment is poorly explored. We therefore aimed to investigate whether the Multidimensional Prognostic Index (MPI), an established tool that assesses measures of frailty and predicts mortality, may help physicians in identifying patients in whom ETF (enteral tube feeding) is effective in terms of reduced mortality. Methods: Observational, longitudinal, multicenter study with one year of follow-up. Data regarding ETF were recorded through medical records. A standardized comprehensive geriatric assessment was used to calculate the MPI. Participants were divided in low (MPI-1), moderate (MPI-2) or severe (MPI-3) risk of mortality. Data regarding mortality were recorded through administrative information. Results: 1064 patients were included, with 79 (13 in MPI 1–2 and 66 in MPI-3 class) receiving ETF. In multivariable analysis, patients receiving ETF experienced a higher risk of death (odds ratio, OR = 2.00; 95% confidence intervals, CI: 1.19–3.38). However, after stratifying for their MPI at admission, mortality was higher in MPI-3 class patients (OR = 2.03; 95%CI: 1.09–3.76), but not in MPI 1–2 class patients (OR = 1.51; 95%CI: 0.44–5.25). The use of propensity score confirmed these findings. Conclusions: ETF is associated with a higher risk of death. However, this is limited to more frail patients, suggesting the importance of the MPI in the prognostic evaluation of ETF. © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolis