Microbiome research in health and disease management: Since 2018, June 27 is observed as the World Microbiome Day with the aim of encouraging researchers worldwide to raise awareness and share their passion and expertise about the microbial world. This year, the day brings into focus the significance of microbiome, its contributions to health, and the measures that need to be adopted for utilising the resources of the vast microbial world for the betterment of mankind.
As the world continues to grapple with a host of lifestyle diseases like obesity, diabetes, cancer and hypertension besides a looming global threat of antimicrobial resistance (AMR), triggered by rampant use of antibiotics, microbiome research, a relatively new but vibrant field of life sciences, opens up enormous possibilities for health and disease management.
Microbiome refers to a cluster of microorganisms (such as fungi, bacteria and viruses) living together as a community in various domains such as human, animal, plant, aquatic and environment. An in-depth understanding of the microorganisms occupying any of these domains can be applied for the improvement of human disease management through effective therapeutic regimens and lifestyle changes.
The human microbiome refers to the complete microorganisms inhabiting various body sites, including skin, ear, nose, oral cavity, genital, gastrointestinal and respiratory tracts, breast milk, saliva and urine. These microorganisms are dynamic and change in response to various environmental factors, such as exercise, diet, and medication.
The widespread notion among the common people is that bacteria are mostly harmful. But it is a fallacious notion. A major proportion of bacteria that comprises a microbiome is beneficial for enhancement of nutrition and immune system of humans. There are only a few pathogenic strains that cause serious infections.
Microbiome research in health management
Some bacterial species orchestrate metabolic functions, strengthen immunity, help in the digestion of food, protect against other bacteria that cause disease, and ameliorate the symptoms associated with inflammatory bowel disease (IBD), autism spectrum disorder (ASD), diabetes, cancer and obesity. Such studies emphasise the importance of balanced microorganisms in maintaining a healthy body.
This can be illustrated by an example. A new born baby at the time of normal delivery is blanketed by a plethora of microorganisms as it passes through the mother’s birth canal, which is further enhanced by colostrum, the first form of breast milk that nourishes the baby. Such microbial colonisations dictate the infant’s ability to resist or contract infections. These findings highlight the importance of breast milk in infant health.
The human gut microbiome has a prominent position with respect to its microbial abundance, diversity and significant involvement in health and disease. But unethical use of antibiotics that has spawned hard-to-treat so-called ‘superbugs’, food poisoning and bacterial infections adversely affect the gut microbiome and lead to intestinal dysbiosis (reduction in microbial diversity and loss of beneficial bacteria). Hence, care must be taken to incorporate fibre-rich food and green, leafy vegetables in the diet to promote the growth of beneficial gut bacteria.
Significant breakthroughs have been made for assessing the diversity of gut microbiome. Initially, it was through culturing of faecal samples. Now the emergence of nucleic acid-based approaches (DNA sequencing) has facilitated the study of specific genes associated with the gut microbiome through big-data generation. With the recent advancements in Next Generation Sequencing (NGS) platforms, it is possible to discover robust microbial biomarkers underlying various diseases.
Scientific innovations in microbiome research open new horizons for start-ups for younger generations. Attempts to therapeutically manipulate the microbiome are also rapidly progressing with respect to reversing a damaged microbiome by faecal microbiota transplantation (FMT) for managing some human diseases. Reports indicate that in Kerala, FMT has already been implemented as a successful therapeutic intervention.
Thus, microbiome research is gaining global attention on account of its integral role in health and disease management. A team of researchers at Rajiv Gandhi Centre for Biotechnology (RGCB) has successfully completed a study that investigates the benefits of probiotic microorganisms of infant faecal and breast milk origin against some antibiotic resistant strains that cause cholera, pneumonia and nasal infections. Also, a study deciphering the effect of postpartum antibiotics administered by the mothers on infant gut microbiome and resistome has been completed successfully.
In order to expand the horizon of microbiome research, the team is currently involved in isolating a probiotic bacterium from the gut that possesses the ability to produce urolithin, a multifaceted nutraceutical, and also in analysing the impact of regular yoga practice in the establishment of a balanced gut microbiome.
The author led a team of young researchers at RGCB for editing a book, titled ‘Human Microbiome: Clinical Implications and Therapeutic Interventions’ published by the international publishing group, Springer. It strives to impart a comprehensive knowledge to health professionals, nutritionists, medical students and scientific research community worldwide and urge them to engage in explanatory studies of the human microbiome.
A better understanding of human microbiome will also throw open a wider vision of other domains of microbiome — animal, plant, aquatic and environment. The field of microbiome research is now rapidly shaping up as an area of great prospects in the domain of new medical treatments, advancing from a fledgling field to an area bristling with medical research. Significantly, it provides an interdisciplinary platform for diverse fields, like agriculture, food science, biotechnology, plant pathology, and human medicine.
(Dr Sabu Thomas is Senior Scientist and Principal Investigator at Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram.)