U. diffracta extract mitigates high fat diet and VD3-induced atherosclerosis and biochemical changes in the serum liver and aorta of rats.

•The ethanol extract of Usnea diffracta shows a positive antiatherogenic effect.•The ethanol extract of Usnea diffracta promotes lipid metabolism.•The ethanol extract of Usnea diffracta reduces the plaque area in atherosclerotic model rats.•The mechanism may be related to the inhibition of TLR5/NF-κB signaling pathway.