Dysregulated retinoic acid signaling in airway smooth muscle cells in asthma.
Amy E DefnetSushrut D ShahWeiliang HuangPaul ShapiroDeepak A DeshpandeMaureen A KanePublished in: FASEB journal : official publication of the Federation of American Societies for Experimental Biology (2021)
Vitamin A deficiency has been shown to exacerbate allergic asthma. Previous studies have postulated that retinoic acid (RA), an active metabolite of vitamin A and high-affinity ligand for RA receptor (RAR), is reduced in airway inflammatory condition and contributes to multiple features of asthma including airway hyperresponsiveness and excessive accumulation of airway smooth muscle (ASM) cells. In this study, we directly quantified RA and examined the molecular basis for reduced RA levels and RA-mediated signaling in lungs and ASM cells obtained from asthmatic donors and in lungs from allergen-challenged mice. Levels of RA and retinol were significantly lower in lung tissues from asthmatic donors and house dust mite (HDM)-challenged mice compared to non-asthmatic human lungs and PBS-challenged mice, respectively. Quantification of mRNA and protein expression revealed dysregulation in the first step of RA biosynthesis consistent with reduced RA including decreased protein expression of retinol dehydrogenase (RDH)-10 and increased protein expression of RDH11 and dehydrogenase/reductase (DHRS)-4 in asthmatic lung. Proteomic profiling of non-asthmatic and asthmatic lungs also showed significant changes in the protein expression of AP-1 targets consistent with increased AP-1 activity. Further, basal RA levels and RA biosynthetic capabilities were decreased in asthmatic human ASM cells. Treatment of human ASM cells with all-trans RA (ATRA) or the RARγ-specific agonist (CD1530) resulted in the inhibition of mitogen-induced cell proliferation and AP-1-dependent transcription. These data suggest that RA metabolism is decreased in asthmatic lung and that enhancing RAR signaling using ATRA or RARγ agonists may mitigate airway remodeling associated with asthma.
Keyphrases
- rheumatoid arthritis
- lung function
- disease activity
- induced apoptosis
- chronic obstructive pulmonary disease
- ankylosing spondylitis
- cell cycle arrest
- cell proliferation
- endothelial cells
- allergic rhinitis
- interstitial lung disease
- cystic fibrosis
- smooth muscle
- air pollution
- oxidative stress
- immune response
- insulin resistance
- signaling pathway
- single cell
- induced pluripotent stem cells
- high fat diet induced
- body mass index
- physical activity
- gene expression
- metabolic syndrome
- risk assessment
- machine learning
- artificial intelligence
- high glucose
- inflammatory response
- human health
- skeletal muscle
- cell cycle