It has become apparent that the molecular and biochemical integrity of interactive families, genera, and species of human gut microflora is critically linked to maintaining complex metabolic and behavioral processes mediated by peripheral organ systems and central nervous system neuronal groupings. Relatively recent studies have established intrinsic ratios of enterotypes contained within the human microbiome across demographic subpopulations and have empirically linked significant alterations in the expression of bacterial enterotypes with the initiation and persistence of several major metabolic and psychiatric disorders. Accordingly, the goal of our review is to highlight potential thematic/functional linkages of pathophysiological alterations in gut microbiota and bidirectional gut–brain signaling pathways with special emphasis on the potential roles of gut dysbiosis on the pathophysiology of psychiatric illnesses. We provide critical discussion of putative thematic linkages of Parkinson’s disease (PD) data sets to similar pathophysiological events as potential causative factors in the development and persistence of diverse psychiatric illnesses. Finally, we include a concise review of preclinical paradigms that involve immunologically–induced GI deficits and dysbiosis of maternal microflora that are functionally linked to impaired neurodevelopmental processes leading to affective behavioral syndromes in the offspring.

Over the course of human history, it has been common to use plants for medicinal purposes, such as for providing relief from particular maladies and self-medication. Opium represents one longstanding remedy that has been used to address a range of medical conditions, alleviating discomfort often in ways that have proven pleasurable. Opium is a combination of compounds obtained from the mature fruit of opium poppy, papaver somniferum. Morphine and its biosynthetic precursors thebaine and codeine constitute the main bioactive opiate alkaloids contained in opium. Opium usage in ancient cultures is well documented, as is its major extract morphine. The presence of endogenous opiate alkaloids and opioid peptides in animals owe their discovery to their consistent actions at particular concentrations via stereo select receptors. In vitro expression of morphine within a microbiological industrial setting underscores the role it plays as a multi-purpose pharmacological agent, as well as reinforcing why it can also lead to long-term social dependence. Furthermore, it clearly establishes a reciprocal effect of human intelligence on modifying evolutionary processes in papaver somniferum and related plant species.