Nasal lavage, blood or sputum: Which is best for phenotyping asthma?

BACKGROUND AND OBJECTIVE: Determination of asthma phenotypes, particularly inflammatory phenotypes, helps guide treatment and management of this heterogeneous disease. Induced sputum cytology has been the gold standard for determination of inflammatory phenotypes, but sputum induction is fairly invasive and technically challenging. Blood and nasal lavage cytology have been suggested as substitutes, but have not been fully verified. The aim of this study is to determine the accuracy of blood and nasal lavage cytometry as indicators of inflammatory phenotypes in asthma. METHODS: Clinical evaluation, Asthma Control Questionnaire (ACQ) and spirometry were performed for 121 adult asthma patients, and blood, nasal lavage and induced sputum samples were taken. Eosinophils and neutrophils were counted in three samples from each subject. Inflammatory phenotypes (eosinophilic, neutrophilic, mixed and paucicellular) and cells counts were analysed using Venn diagram and receiver operating characteristic (ROC) curve, respectively. RESULTS: ACQ score, spirometry and bronchodilator response did not differ among subjects with different inflammatory phenotypes. Inflammatory phenotypes defined by nasal lavage cytometry were in better concordance than those defined by blood cell counts with phenotypes determined by sputum cytology, and were significantly correlated with sputum phenotypes. For eosinophilia, nasal lavage cytology showed better accuracy than blood cytology (area under the curve (AUC): 0.89 vs 0.65). For all phenotypes, sensitivity and positive and negative predictive power were higher for nasal lavage cytometry than for blood. Blood cell counts gave a high level of false positives for all inflammatory phenotypes. CONCLUSION: We recommend nasal lavage cytology over blood cell count as a substitute for sputum cytology to identify inflammatory phenotypes in asthma.

Neolignans from Nectandra megapotamica (Lauraceae) Display in vitro Cytotoxic Activity and Induce Apoptosis in Leukemia Cells.

Nectandra megapotamica (Spreng.) Mez. (Lauraceae) is a well-known Brazilian medicinal plant that has been used in folk medicine to treat several diseases. In continuation of our ongoing efforts to discover new bioactive natural products from the Brazilian flora, this study describes the identification of cytotoxic compounds from the MeOH extract of N. megapotamica (Lauraceae) leaves using bioactivity-guided fractionation. This approach resulted in the isolation and characterization of eight tetrahydrofuran neolignans: calopeptin (1), machilin-G (2), machilin-I (3), aristolignin (4), nectandrin A (5), veraguensin (6), ganschisandrin (7), and galgravin (8). Different assays were conducted to evaluate their cytotoxic activities and to determine the possible mechanism(s) related to the activity displayed against human leukemia cells. The most active compounds 4, 5 and 8 gave IC50 values of 14.2 ± 0.7, 16.9 ± 0.8 and 16.5 ± 0.8 µg/mL, respectively, against human leukemia (HL-60) tumor cells. Moreover, these compounds induced specific apoptotic hallmarks, such as plasma membrane bleb formation, nuclear DNA condensation, specific chromatin fragmentation, phosphatidyl-serine exposure on the external leaflet of the plasma membrane, cleavage of PARP as well as mitochondrial damage, which as a whole could be related to the intrinsic apoptotic pathway.