Relaxing the "second brain": nutrients and bioactive compounds as a therapeutic and preventive strategy to alleviate oxidative stress in the enteric nervous system

The enteric nervous system (ENS) regulates several functional and immunological processes in the gastrointestinal tract. However, some diseases can disrupt the ENS functionality, impacting the behavior of enteric neurons and enteric glial cells by increasing the accumulation of reactive oxygen species. Oxidative stress is considered to be a trigger for alterations in these cells' morphology, density, and neurochemical patterns. In light of this, nutritional strategies are a growing field of investigation regarding their potential to modulate enteric neurons and enteric glial cells through reduced reactive oxygen species production. Moreover, several lines of evidence show that nutrients are related to counteracting oxidative stress. Some studies have evaluated the potential of nutrients with antioxidant roles (such as amino acids, polyphenols, prebiotics, vitamins, and specific extracts obtained from foods) to modulate the ENS. Thus, this review discusses how bioactive compounds and nutrients can impact the ENS by alleviating oxidative stress.