Table 1.

Studies on PPARs and their ligands during viral infections.

Pathogen	Study Model	Intervention	PPAR Status	Mechanism	Ref.
IAV, RSV	AMs, mice	PpargΔLyz2 mice	↓	Regulation of PPARγ through STAT1 activation following IFN signaling	[76]
IAV	AMs, human lung macrophages, mice	PpargΔLyz2 mice, Bleomycin	↓	Increased influenza-induced pulmonary collagen deposition in PPARγ-deficient mice	[78]
IAV	A549 cells, mice	Emodin and its analogs	↑	Activation of PPARα/γ and AMPK, decreased fatty acid biosynthesis and increased ATP level	[79]
MERS-CoV	THP-1 cells, primary human monocytes	siRNAs	↑	MERS-CoV S glycoprotein interaction with DPP4 leading to IRAK-M and PPARγ expression	[87]
CHIKV	Vero cells, RAW264.7 cells	Telmisatran, PPAR-γ antagonist GW9662	↓	Activation of PPAR-γ and inhibition of AT1 by telmisartan	[88]
HIV	Primary rat astrocytes, microglia, rats	gp120ADA, Rosiglitazone, Pioglitazone	↓	Induction of inflammatory response and decrease in GLT-1 expression in the brain by gp120	[89]
HBV	HepG2.2.15, Huh7, HepG2-NTCP ells	OS_128167, overexpression and downregulation studies, HBV transgenic mice	-	Activation of HBV core promoter by SIRT6 through upregulation of PPARα	[90]
HCV	Huh7.5 cells	Calciterol, Linoleic acid, Ly171883, Wy14643	-	Activation of VDR but inhibition of PPARα/β/γ by calcitriol	[91]

Abbreviations: AMPK, AMP-activated protein kinase; AMs, Alveolar macrophages; AT1, Angiotensin 1; CHIKV, Chikungunya virus; DPP4, Dipeptidyl-peptidase 4; GLT-1, Glutamate transporter 1; HBV, Hepatitis B virus; HCV, Hepatitis C virus; HIV, human immunodeficiency virus; IAV, Influenza A virus; IFN, interferon; IRAK-M, Interleukin-1 receptor-associated kinase 3; MERS-CoV, Middle east respiratory syndrome corona virus; RSV, Respiratory syncytial virus; SIRT6, Sirtuin 6; STAT1, Signal transducer and activator of transcription 1; VDR; Vitamin D receptor; ↑, increase/activation; ↓, decrease/inhibition; -, not reported.