Scientists discuss how common ecological models can improve gut health

When disturbances upset the balance of a forest, field, or stream, ecologists practice ecological restoration to assist ecosystem recovery. In "Gut Microbiota and Human Health: Insights from Ecological Restoration" published in The Quarterly Review of Biology (June 2018), Matthew R. Orr, Kathryn M. Kocurek, and Deborah L. Young explore the potential applications of ecological restoration to medicine. By integrating these disciplines, the authors offer new insights into research and treatment of chronic disease.

Utilizing an interdisciplinary perspective, the authors analyze the role humans perform as ecosystems. Humans act as hosts for a multitude of interdependent microbe species that are beneficial to overall gut health. The microbes, in return, offer benefits--known as ecosystem services--that impact nutrition and control both immunity and body mass.

Microbial imbalance--also known as dysbiosis--within the gut is linked to the development of chronic diseases, including obesity, cancer, and autoimmune disorders.

"A principal goal of ecological restoration is to improve the ability of degraded, damaged, or destroyed ecosystems to deliver ecosystem services. Medicine shares the same goal whenever perturbation of symbiotic microbes jeopardizes human health," the authors write.

In the article, the authors discuss how methods, such as microbiome-wide association studies (MWAS) and microbial GPS, can help identify conditions that promote healthy gut microbe communities.

Numerous studies indicate that greater diversity of gut microbes is linked to better health. Individuals who live in Westernized societies and adhere to industrial diets exhibit lower levels of gut microbiota diversity in comparison to those who live in more traditional societies.

Restoring gut structure to a healthier composition can occur through either passive restoration or active restoration. Passive restoration removes the source of the disturbance with the hope that the ecosystem will heal by itself. Diet modifications are a form of passive restoration. If passive restoration fails, however, active restoration techniques, such as fecal microbiota transplants (FMT) may also be needed. An important insight from ecological restoration, and one that is generally ignored in Western medicine, is that active interventions are less likely to work if passive interventions are not implemented and sustained.

Ecological restoration thereby identifies patients as critical participants in the health of their gut communities, whereas Western approaches to chronic disease often absolve patients of lifestyle changes that promote healing.

The authors elaborate on how common ecological models--known as structure-function models--can serve as tools for assessing the effectiveness of gut health treatments. Applying a rivet-redundancy model, in particular, could prove useful, considering evidence indicates a rivet-redundancy relationship exists within the gut. In this model, function in an ecosystem is not altered until a significant change in species diversity occurs. Microbiota in the gut exhibit functional redundancy. Although some microbe species may be absent, others perform the functions of the missing species. This redundancy can pose issues when supposedly "healthy" FMT donors actually possess lower levels of gut diversity. While FMT protocols may currently overlook donor deficiency, the use of these models can help detect factors that may be inhibiting FMT success and increasing the probability of relapse.

Source: http://www.journals.uchicago.edu/