Viruses are efficient metabolic engineers that actively rewire host metabolic pathways to support their lifecycle. Charting SARS-CoV-2 induced metabolic changes in lung cells could offer insight into COVID-19 pathogenesis while presenting new therapeutic targets.
We show that the transcriptional response SARS-CoV-2 in primary lung epithelial cells and biopsies of COVID-19 patients is predominantly metabolic. This transcriptional signature was dominated by changes to lipid metabolism and the induction of IRE1 and PKR pathways of endoplasmic stress in a process regulated by several viral proteins. Transcriptional regulatory analysis of these changes reveals small clusters of transcription factors modulating key enzymes in each pathway. The upregulation of glycolysis and the dysregulation of the citric acid cycle was mediated by NFκB and RELA. While the upregulation of fatty acid and cholesterol synthesis showed a more complex control conditionally modulated by ER-stress activated PPARγ, C/EBP, and PPARα. Viral protein ORF3a appeared to interact with all three pathways suggesting both direct and indirect modulation of host metabolism.
In addition, we show that PPARα-agonist fenofibrate reversed the metabolic changes induced by SARS-CoV-2 blocking viral replication.
Taken together, our data suggest that elevated lipid metabolism may underlie aspects of COVID-19 pathogenesis, offering new therapeutic avenues in targeting this critical pathway on which the virus relies.