“…Although the mechanisms that trigger and/or aggravate the inflammatory response are not fully understood, inflammation precedes vascular lesion supports that immune dysregulation is responsible for vascular remodeling in PAH (Tamosiuniene et al, 2011). Increasing evidence suggested that a healthy gut microbial community contributes to maintaining the host immune homeostasis (Kim et al, 2016;Clavel et al, 2017), and gut dysbiosis is associated with a variety of inflammation-related diseases, including atherosclerosis (Jonsson and Bäckhed, 2017;Yoshida et al, 2018;Wu et al, 2021), obesity (Yoshimoto et al, 2013;Canfora et al, 2019;Arnoriaga-Rodrıǵuez et al, 2020), multiple sclerosis (Kadowaki et al, 2019;Kadowaki and Quintana, 2020;Pröbstel et al, 2020), chronic transplantation rejection (Wu et al, 2020), autoimmune diseases (Manfredo Vieira et al, 2018;Fine et al, 2020;McPherson et al, 2021;Pandey et al, 2021), and cancers (Zhu et al, 2020;McPherson et al, 2021). Considering that inflammation is a crucial factor in the initiation and progress of PAH (Almodovar et al, 2011;Stacher et al, 2012;Graham et al, 2013;Simonneau et al, 2013;Saito et al, 2017;Qian et al, 2019).…”