Heparin-binding epidermal growth factor-like growth factor (HB-EGF) activates p38 to affect pulmonary fi brosis

Objective: We aimed to examine whether heparin -binding epidermal growth factor -like growth factor (HB-EGF) affects the lung fibrosis process through the activation of p38 protein in mitogen-activated protein kinases (MAPK) signaling pathway, as well as the expression of downstream inflammatory factors. Methods: The expression levels of HB-EGF, collagen type I (COL -I), and hexokinase 2 (HK2) in peripheral blood mononuclear cells (PBMCs) of patients with connective tissue disease -related interstitial lung disease (CTD-ILD) were examined by qPCR, Western blotting and ELISA. Results: In vitro experiments showed that HB-EGF was increased in almost all subtypes [rheumatoid arthritis (RA), systemic sclerosis (SSc) and idiopathic inflammatory myopathies (IIMs)] as well as in all groups (P < 0.05). For embryonic lung fibroblast (A549) cells, the expression levels of HK2 and a -smooth muscle actin ( a-SMA) genes were elevated during 0-4 h and then plateaued. Transforming growth factor - b1 (TGF- b1) induced fibrosis in human embryonic lung fibroblasts (MRC-5) cells and A549 for a certain period of time, but the degree of induction varied, which may be related to the redifferentiability of cells at different spatial locations. Moreover, HB-EGF at concentrations above 1 ng/ml stimulation increased COL -I expression (P < 0.05), and for a-SMA gene, even 1 ng/ml concentration of HB-EGF had a stimulatory effect, and different concentrations of HB-EGF did activate the expression of p38 in a concentration -dependent manner within a certain concentration range, and by The qPCR results showed that for interleukin 6 (IL -6), an inflammatory factor regulated downstream of p38, the expression was significantly increased in A549 cells compared to control (P < 0.05), but tumor necrosis factor - a (TNF- a) expression was downregulated (P < 0.05), but for interleukin-1 b (IL -1 b) gene, there was no significant difference in A549 cells, and expression was downregulated in MRC-5 cells. Therefore, it is suggested that HB-EGF regulates the expression of inflammatory factors through p38 will be differential across cells. Conclusion: Our study shows that HB-EGF can suppress pulmonary fibrosis through downstream activation of p38/MAPK pathway activity, as well as the expression of various inflammatory factors downstream of it. (c) 2024, The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V. This is an open access article under the CC BY -NC -ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).