The microbiota–gut–brain axis theory: A new perspective to unlock the pathological mechanism of constipation

Constipation, a common gastrointestinal system disease, has a variety of side effects, but its pathogenesis is diverse and complex. Thus, its treatment is affected by a variety of factors, such as intestinal flora imbalance, nervous system problems (cerebrovascular disease, cognitive impairment or dementia, Parkinson’s disease) and other pathological diseases (hypothyroidism, hypercalcemia and others). With the rise of the microbiota-gut-brain (MGB) axis theory, people's understanding and treatment methods for gastrointestinal diseases such as constipation have also undergone significant changes. Therefore, this paper focuses on the MGB axis and constipation, including the 3 main regulatory pathways of this axis, the gut microbial metabolites and the regulation of neurotransmitters, and the methods and applications of treating constipation and other diseases on the basis of this axis. Further clarification of the pathways and influencing factors related to the MGB axis will help elucidate the pathophysiological mechanisms of constipation and play a key role in the rational treatment of human gastrointestinal diseases.