Gut feelings: the microbiota-gut-brain axis on steroids

Abstract

The intricate connection between central and enteric nervous systems is well established with emerging evidence linking gut microbiota function as a significant new contributor to gut-brain axis signaling. Several microbial signals contribute to altered gut-brain communications, with steroids representing an important biological class that impacts central and enteric nervous system function. Neuroactive steroids contribute pathologically to neurological disorders, including dementia and depression, by modulating the activity of neuroreceptors. However, limited information is available on the influence of neuroactive steroids on the enteric nervous system and gastrointestinal function. In this review, we outline how steroids can modulate enteric nervous system function by focusing on their influence on different receptors that are present in the intestine in health and disease. We also highlight the potential role of the gut microbiota in modulating neuroactive steroid signaling along the gut-brain axis.

Neuroactive metabolites and bile acids are altered in extremely premature infants with brain injury

“…Furthermore, they are influenced by the gut microbiome, presumably through modulating GABA A and NMDA receptors. 72 Steroid sulfation and desulfation greatly affect the biological activity, regulating the steroid bioactivity and, in many cases, unconjugated and sulfated steroids acting in opposite ways on the same receptors. Steroid sulfates also have an important role in the regulation of steroid metabolism and transport.…”

Neuroactive metabolites and bile acids are altered in extremely premature infants with brain injury

“…in neuro modulation and as a contributor to gut-brain axis signaling 54 and the sulfonation of steroids by gut bacteria was associated with the alteration of immune cell trafficking in the host. 55…”

Targeting the gut microbiome in the management of sepsis-associated encephalopathy

“…In addition, corticosteroids are critical in the host response to infection. Though their anti-inflammatory and immunomodulatory effects are well-known, elevation in glucocorticoid concentrations may also reduce gut microbiome diversity ( 34 ). Rodents treated with a single dose of dexamethasone developed increases in the number of pathogenic anaerobic and coliform bacteria ( 35 ).…”