Inhaled glucocorticoid-induced metabolome changes in asthma

Abstract

Objective: The aim of this study was toidentify dose-related systemic effects of inhaled glucocorticoids (GCs) on the global metabolome.

Design and methods: Metabolomics/lipidomic analysis from plasma was obtained from 54 subjects receiving weekly escalating doses (µg/day) of fluticasone furoate (FF; 25, 100, 200, 400 and 800), fluticasone propionate (FP; 50, 200, 500, 1000 and 2000), budesonide (BUD; 100, 400, 800, 1600 and 3200) or placebo. Samples (pre- and post-dose) were analysed using ultrahigh-performance liquid chromatography-tandem mass spectroscopy and liquid chromatography-mass spectrometry. Ions were matched to library standards for identification and quantification. Statistical analysis involved repeated measures ANOVA, cross-over model, random forest and principal component analysis using log-transformed data.

Results: Quantifiable metabolites (1971) had few significant changes (% increases/decreases; P < 0.05) vs placebo: FF 1.34 (0.42/0.92), FP 1.95 (0.41/1.54) and BUD 2.05 (0.60/1.45). Therapeutic doses had fewer changes: FF 0.96 (0.36/0.61), FP 1.66 (0.44/1.22) and BUD 1.45 (0.56/0.90). At highest/supratherapeutic doses, changes were qualitatively similar: reduced adrenal steroids, particularly glucuronide metabolites of cortisol and cortisone and pregnenolone metabolite DHEA-S; increased amino acids and glycolytic intermediates; decreased fatty acid β-oxidation and branched-chain amino acids. Notable qualitative differences were lowered dopamine metabolites (BUD) and secondary bile acid profiles (BUD/FF), suggesting CNS and gut microbiome effects.

Conclusions: Dose-dependent metabolomic changes occurred with inhaled GCs but were seen predominately at highest/supratherapeutic doses, supporting the safety of low and mid therapeutic doses. At comparable therapeutic doses (FF 100, FP 500 and BUD 800 µg/day), FF had the least effect on the most sensitive markers (adrenal steroids) vs BUD and FP.

Figure 1

Study design. *165 subjects were screened; 56 subjects were enrolled; 108 subjects excluded (76 subjects did not meet eligibility criteria; 15 subjects withdrew consent, 1 subject withdrawn at investigator’s discretion; 18 subjects were excluded for ‘other’ reasons); 54 subjects were randomised; 2 subjects withdrew prior to randomisation. Pre-dose plasma samples for cortisol and metabolomic analysis were also taken before the start of each period. ^†1 subject withdrawn. ^‡2 subjects withdrawn/excluded. AMP PC₂₀, provocative concentration of adenosine-5’-monophosphate resulting in a decline of ≥ 20% in FEV₁; BUD, budesonide; FEV₁, forced expiratory volume in 1 s; FF, fluticasone furoate; FP, fluticasone propionate; GCs, glucocorticoid; R, randomisation; SABA, short-acting beta-agonist.

Figure 2

Relationship between dose and adrenal steroids measured via metabolomics (A) cortisone, (B) cortolone glucuronide and (C) DHEA-S all based on 12-h post-dose plasma sample on day 8 and (D*) 0–24-h-weighted mean plasma cortisol based on 24-h serial plasma samples taken between pre-PM dose on day 6 and pre-PM dose on day 7. *Image developed from data previously published in Daley-Yates et al. (2020) (16). BUD, budesonide; FF, fluticasone furoate; FP, fluticasone propionate; ICS, inhaled corticosteroid; PM, post meridian.

Figure 3

Steroid molecule pathways. All structures available from PubChem database at https://pubchem.ncbi.nlm.nih.gov/.

Figure 4

Intra-individual comparison of complex lipids. (A) Arrows point towards increased TAG and DAG species and decreased MAG species. Red boxes in the heat map represent significantly increased biochemicals (P ≤ 0.05). Green boxes in the heat map represent significantly decreased biochemicals (P ≤ 0.05). Pink and light green boxes represent biochemicals which are trending towards a significant increase or decrease, respectively (0.05 < P < 0.10). (B) TAG synthesis and hydrolysis pathways. *The sum of molecules in each class. BUD, budesonide; DAG, diacylglycerol; FF, fluticasone furoate; FP, fluticasone propionate; FFA, free fatty acids; GPAT3, glycerol-3-phosphate acyltransferase 3; LPIN1, Lipin1; MAG, monoacylglycerol; TAG, triacylglycerol.