The past decade has been phenomenal in providing tremendous insight into the previously unsuspected enormous diversity of the human intestinal microbiome highlighting the fact that the gut harbours more than 100 trillion organisms. This is the largest consortium of microorganisms in the human body that have the ability to function as a ‘virtual’ organ system. Advances in high throughput sequencing tools have galvanised the study of the molecular cross talk between commensal organisms and the host leading to the realisation that alterations in the balance of the intestinal microflora results in dysbiosis and ultimately in clinical disease. Our understanding of human physiology has transformed and created a new paradigm in the way we think and regulate health and disease. The focus is, therefore, shifting from individual pathogens to an ecological approach that considers the microbial community as a whole.
The scientific quest has been to identify mechanisms that can favourably modulate the gut flora, which has resulted in research in the area moving at a breathtaking pace. Illuminating clinical work and a series of seminal publications mostly from the developed world have shown that probiotics have immense potential in positively impacting the gut flora. In controlled clinical trials probiotic bacteria have demonstrated benefit in preventing and treating gastrointestinal diseases that include infectious diarrhoea in children, Clostridium difficile induced infection, Inflammatory bowel diseases and modulation of the immune system both at a systemic and mucosal level. Both researchers and clinicians are embracing this new tool for prevention and treatment of diseases that has changed the face of the health map in the Western world.
With the growing quest for optimal health, probiotics are slowly but surely finding their way to the developing world, especially India, where the concept could be a welcome addition to the containment of disease. A country like ours is plagued with early and frequent exposure to intestinal pathogens that begins a cycle that affects digestion, nutrient absorption, growth and immunity. Children suffer from repeated infections with either overt or chronic diarrhoea or subclinical enteropathy resulting in acute and chronic under nutrition, which leads to more severe infections. Probiotics in the form of a simple, safe and ubiquitous intervention could be a useful modality in improving nutrition and microbiome function.
Probiotic bacteria generally execute their biological role in the gut through a plethora of antipathogenic mechanisms that include direct antagonism, immune modulation and competitive exclusion. However these mechanisms differ according to the strain of bacteria and the disease model tested. Therefore, it is important that each probiotic strain is backed by its own dossier of scientific studies to validate their health effects. The studies should, of course, be conducted using similar intervention levels as those recommended for consumption.
By way of illustration, Lactobacillus casei strain Shirota, one of the oldest probiotic organisms was discovered in 1930 by a Japanese scientist Dr Minoru Shirota who after a rigorous search, isolated this strain from a group of 300 lactobacilli and formulated it as a fermented milk drink called Yakult which by virtue of its ability to improve intestinal health and augment the host’s immunity helped prevent disease and infection in Japan. After its launch in Japan in 1935 and successful journey in more than 30 countries Yakult has now entered India and is making its way to those who benefit from its consumption. This strain of bacteria in Yakult is backed by more than 75 years of scientific research. The product has received FOSHU (Food for Specified Health Uses) accreditation by the Consumer Affairs agency in Japan for its scientifically proven health benefits.
Although the Indian market is still nascent capturing the understanding and need for the category, the increasing scientific credibility and the new emerging holistic concept of health that focuses on promoting good health rather than the manifestations of ill health will definitely result in a new public health movement. The challenge, however, would be to develop a well-planned strategy that would allow probiotics to get ingrained into the public health system without being seen as a medicine. Of course a concerted effort from manufacturers, scientists and regulators and a sound regulatory framework will be critical in ensuring that scientific and clinical excellence are the driving forces for the growth of the category and well documented products are available to all.
As we move from Metchnikoff to Microbiome, we find ourselves in a time of optimism for the potential therapeutic haul to be derived from interventions that can favourably modify the gut microbiome. These are exciting and challenging times.
Brief about the author
Neerja Hajela, Head, Science, Yakult Danone India, a Japanese French joint venture between Yakult Honsha Co. Ltd of Japan and Groupe Danone of France both global leaders in the area of probiotics. She has been involved in the development, planning and implementation of scientific programmes for the company. Having worked for Ranbaxy Pvt Ltd and Biotech Consortium India Limited (BCIL), a Department of Biotechnology undertaking, she carries with her an experience of over 15 years. She also has to her credit publications in peer reviewed journals and has contributed articles on probiotics for several magazines.