K2 potentiates extraction and transport of calcium deposits from soft tissues to the bones and teeth. Nattokinase dissolves fibrin deposits which contribute to formation of plaque structures in arterial walls. Natto (only in combination with Red Yeast Rice) has been found to lower blood lipids. Some variants of RYR mirror Lovastatin’s activity.
I think you might not be remembering what “red” item helped nattokinase.
It's “Korean Red Ginseng.”
“Male white rabbits were fed a high cholesterol diet supplemented with red ginseng (RG) or red ginseng plus nattokinase (RGNK). RG and RGNK significantly reduced increased serum triglycerides levels and aortic plaque area in a hypercholesterol diet fed rabbits. Moreover, only RGNK reduced hepatic cholesterol and cholesteryl ester transfer protein activity levels. Therefore, the present study suggests RGNK might be a potential therapeutic approach for atherogenesis.”