{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T22:17:25Z","timestamp":1774995445989,"version":"3.50.1"},"reference-count":62,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,4,1]],"date-time":"2018-04-01T00:00:00Z","timestamp":1522540800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diseases"],"abstract":"<jats:p>The brain and the gut are connected from early fetal life. The mother\u2019s exposure to microbial molecules is thought to exert in utero developmental effects on the fetus. These effects could importantly underpin the groundwork for subsequent pathophysiological mechanisms for achieving immunological tolerance and metabolic equilibrium post birth, events that continue through to 3\u20134 years of age. Furthermore, it is understood that the microbiome promotes cues that instruct the neonate\u2019s mucosal tissues and skin in the language of molecular and cellular biology. Post birth mucosal lymphoid tissue formation and maturation (most probably including the vermiform appendix) is microbiota-encouraged co-establishing the intestinal microbiome with a developing immune system. Intestinal mucosal tissue maturation loops the brain-gut-brain and is postulated to influence mood dispositions via shifts in the intestinal microbiome phyla. A plausible appreciation is that dysregulated pro-inflammatory signals from intestinal resident macrophages could breach the loop by providing adverse mood signals via vagus nerve afferents to the brain. In this commentary, we further suggest that the intestinal resident macrophages act as an upstream traffic controller of translocated microbes and metabolites in order to maintain local neuro-endocrine-immunological equilibrium. When macrophages are overwhelmed through intestinal microbiome and intestinal epithelial cell dysbiosis, pro-inflammatory signals are sustained, which may then lead to mood disorders. The administration of probiotics as an adjunctive medicine co-administered with antidepressant medications in improving depressed mood may have biological and clinical standing.<\/jats:p>","DOI":"10.3390\/diseases6020023","type":"journal-article","created":{"date-parts":[[2018,4,2]],"date-time":"2018-04-02T12:32:20Z","timestamp":1522672340000},"page":"23","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["The Brain\u2013Intestinal Mucosa\u2013Appendix\u2013 Microbiome\u2013Brain Loop"],"prefix":"10.3390","volume":"6","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7490-9298","authenticated-orcid":false,"given":"Luis","family":"Vitetta","sequence":"first","affiliation":[{"name":"Sydney Medical School, The University of Sydney, Sydney 2006, Australia"},{"name":"Medlab Clinical Ltd., Sydney 2015, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gemma","family":"Vitetta","sequence":"additional","affiliation":[{"name":"Medlab Clinical Ltd., Sydney 2015, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0090-7895","authenticated-orcid":false,"given":"Sean","family":"Hall","sequence":"additional","affiliation":[{"name":"Medlab Clinical Ltd., Sydney 2015, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.ceb.2017.04.006","article-title":"Regulation of gastrulation movements by emergent cell and tissue interactions","volume":"48","author":"Williams","year":"2017","journal-title":"Curr. 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