The role of microbiomes in modern living

From before the day we are born until the day we die, our microbiome shapes our health and wellbeing.

By Pro Vice-Chancellor (Research Capability) - Professor Ashley Franks

To preserve the essential community of microbes in our gut, we evolved the appendix as our personal biobank, providing a safehouse for the microbiome in times of extreme gastrointestinal distress. The human gut contains many species of microorganisms, many of which have a role in maintaining good health. Microbes are central to our digestion; they break down food and produce nutrients, and they tinker with our immune and neurological systems to affect our health throughout life.

Our gut microbiome has incredibly broad effects; it influences our mood and behaviour, provides protection against neurodegenerative and other diseases, can drive responses to drug treatment, modulate chronic diseases and contribute to an individual’s resilience. The microbiome even produces a range of neurological signals, influences inflammation throughout the body, and drives development of essential body functions throughout our lives. The gut microbiota can be affected by diet, diseases and drugs, especially antibiotics. Our modern lifestyle and diet are linked as well to changes in our microbiome which can lead to dysbiosis and the prevalence of many “modern diseases”.

It is no wonder that the public’s interest in the microbiome has grown exponentially. The importance of the microbes we carry with us has only recently been appreciated. Benefits of our microbes include assisting your immune system to fight disease causing agents, protecting a newborn baby from infections as it adjusts to life outside of the mother’s womb, reducing necrosis of intestines in preterm babies, lessening severity of neurological disorders, improving mental and physical resilience and even increasing cognitive ability. The microbiome is now mainstream; the Australian probiotics market was estimated to be worth $318 million in 2019, sales of functional foods are expected to be worth $228.79 billion globally by 2025 and Choice Magazine is already providing advice on home microbiome testing kits.

One thing that must be overcome is the complexity of the system. There are a wide variety of nutritional inputs including age, gender, geographical location, physical activity, obesity, host genetics, lifestyle, pets and medications amongst others that can influence microbial composition and function. Changes that have occurred to our lifestyles have outpaced evolution and we must now take over the role of the appendix to ensure we maintain a diverse and functional microbiome throughout our lives.

The complexity of the microbiome and its interactions with the gut makes this incredibly difficult. While evolution took millions of years to perfect these interactions, we must work across diverse fields to ensure we have the knowledge to ensure beneficial functional outcomes of gut microbes with our organs at a personal level.

We must work with systems within systems to understand how microbes shape our lives.

Phage, bacteria, fungi and yeast all interact spatially and temporally along the gut to affect inflammation, innate and adaptive immune responses, our nervous, endocrine and cardiovascular systems and even reproduction. Even our decision-making capabilities can be driven by differences in our microbiome. Technology advances now makes it possible to combine our knowledge across multiple different areas to work with these complex systems.

Universities are becoming an essential component for the development of ways to harness the microbiome of human health and wellbeing. Claims about food sources and supplements require independent backing and basis in solid science. A mechanistic understanding needs microbiologists, neurologists, psychologists, computer scientists, engineers, nutritionist and many others to work together to tackle the overall complexity of these systems. At La Trobe, our microbiologists in applied and environmental microbiology have teamed with neuroscientist Elisa Hill, head of the Gut-brain Axis laboratory at RMIT, and industry partners to form a world leading gut-microbiome research group tackling basic to applied research problems to ensure our research efforts are solution driven and are providing real world commercial outcome opportunities.

Bringing a whole University approach to microbiome research has provide notable success. We have identified a microbiome before birth, difference in response to antidepressants based on gender and how a point mutation associated with the brain drives changes in the gut. We have used our knowledge to isolate specific microbes from the bee gut for VernxPeribiotics to provide branched fats which mimic vernix caseosa, the waxy coating found on babies at birth, for use as a prebiotic to improve gut health. We are using natural processes for Prevatex to increase desirable traits in their protective probiotic microbes that are known to be lost in our modern gut microbiome due to the western diet and changes in lifestyle. We have also ensured that targeting specific pathogenic microbes within the gut with new targeted therapeutics developed by Immuron Limited does not have detrimental effects on the microbiome. We are using an interdisciplinary approach to elucidate the effects of gut microbial metabolites on neuroinflammation pathways, neurodevelopment and behavior, GI inflammation and function in mouse models of autism for Axial Therapeutics. The ability to combine microbiology, neurobiology, nutrition and behaviour has gained interest from defense organisations to build resilience and maintain cognition under extreme stress. We are interested in continuing to expand our work with industry on discovery, potential therapeutic target identification, gut-brain axis innovation and engineering of the microbiome for health and well-being outcomes.

These programs have already identified indicator species and therapeutic targets for a range of diseases, ways to drive the functional profile of the gut and how our own genetics are important in driving these interactions. While “we are what we eat”, choosing what to eat is an incredibly complex decision that requires the hardcore multidisciplinary data we are collating.

La Trobe Industry contact: Hope Terdich, Manager – Marketing and Communications, h.terdich@latrobe.edu.au