NPPA and major depressive disorder: In addition, we have also demonstrated that acupuncture can improve depression (Bao et al., 2021) and peripheral KP metabolism (Bao et al., 2016, 2021) in CD, and that the effects of electroacupuncture and moxibustion on brain function in CD patients are related to the brain steady-state afferent processing network and the default mode network, respectively (Bao et al., 2017).