Pulmonary fibrosis involves gradual exchange of normal lung parenchyma with fibrotic tissue. The lung's compliance decreases and ventilation decreases when lung tissue becomes diseased and fibrotic. There are several studies suggesting that fibrocytes mediate wound healing and fibrotic tissue repair. Years of such fluctuations eventually produce small cysts and/or areas of dense or fibrotic tissue. Excessive thickened synovium, filled with cells and fibrotic collagenous tissue, can physically restrict joint movement. GPR40 was discovered to be a major mediator in pathologic fibrotic pathways in 2018. To treat infarction, it is important to prevent the formation of fibrotic scar tissue. The excessive transformation to fibrotic tissue negatively affects the function and structure of the heart. For delayed surgery, the most common reason was fibrotic adhesions. In the initial phase of the disease, the mucosa feels leathery with palpable fibrotic bands. Gammaherpesviruses may be a cause of chronic fibrotic lung diseases in humans and in animals. The bone marrow in a typical case is hypercellular and diffusely fibrotic. These tests can be necessary to diagnose between infection, inflammation, or fibrotic conditions. Liver cells attempt to regenerate in an increasingly fibrotic setting. In later stages, the liver becomes scarred (fibrotic).