Based on the concentrations of TGF-β1 used in cell models of pulmonary fibrosis and PEA in in vitro experiments as reported in the literature, we selected a concentration of 5 ng/mL for TGF-β1 to stimulate the cells and 10 μM for PEA in the subsequent experiments (Ohara et al., 2018; Wang et al., 2020; Schiano Moriello et al., 2022; Niu et al., 2023; Ma et al., 2024). Here, TGFB1 is linked to pulmonary fibrosis.