PPT1 and Myocardial fibrosis: Long‐term administration of D‐gal in rodents can mimic the overproduction of reactive oxygen species caused by physiological aging, a common way to induce aging in animals in vivo.[38, 39] By verifying transgenic mice with PPT1 knockout in macrophages, we found that knocking out PPT1 in macrophages could significantly reduce D‐gal‐induced aging‐related myocardial fibrosis and inflammation in mice.