id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-321427-bwcpd6im	Yee, Min	Neonatal hyperoxia enhances age-dependent expression of SARS-CoV-2 receptors in mice	2020-07-22		.txt	text/plain	2154	114	58	Instead, we made the surprising discovery that expression of Ace2 and Tmprss2 mRNA increases as mice age and is accelerated by exposing mice to neonatal hyperoxia. Our finding that early life insults such as hyperoxia enhances the age-dependent expression of SARS-CoV-2 receptors in the respiratory epithelium helps explain why COVID-19 lung disease is greater in the elderly and people with pre-existing co-morbidities. When quantified, neonatal hyperoxia increased the number of alveolar cells expressing ACE2 by 148 approximately 50% at 2, 6 and 12 months of age (Figure 4b) . The levels of Tmprss2 mRNA and protein were examined in the lungs of 2-, 12-and 18-month-old mice that were exposed to neonatal hyperoxia and room air from PND0-4 by qRT-PCR 168 and western blotting. As observed for Ace2 expression, 173 exposure to ≥ 60% oxygen from PND4-0 was required to significantly increase the levels of Tmprss2 174 mRNA in the lungs of mice at 2 months of age (Figure 6c ).	./cache/cord-321427-bwcpd6im.txt	./txt/cord-321427-bwcpd6im.txt