PPARA and COVID-19: As shown, in COVID-19 patients, glycolysis-related enzymes, including HK1/HK3, ALDOA, TPI1, PGK1, GAPDH, ENO1, PKM2, and LDHA/LAHB, were significantly upregulated by HIF-1 signaling; the fatty acid metabolic genes ASCL1, ASCL4 and ASCL5 were upregulated by PPAR signaling; and CPT1A was upregulated by AMPK signaling.