Animal experiments have also demonstrated that lung injury associated with CHF is characterized by excessive collagen deposition in the alveoli, inside the vessels, and in the vascular walls of large vessels, accompanied by the accumulation of leukocytes and macrophages and increased levels of transforming growth factor-β1 (TGF-β1), TNF-α, and Toll-like receptor-4 (TLR4) mRNA or protein content in the lungs [12]. Here, TGFB1 is linked to congestive heart failure.