July 25, 2012 • Volume 1 / No. 1

Q & A with Drs. Linda Duffy and Crystal McDade-Ngutter—Advancing the Field of Probiotic Research

Dr. Duffy is a Program Officer for Probiotics, Pediatrics, Nutrition, and Gastrointestinal Health, Division of Extramural Research at the National Center on Complementary and Alternative Medicine. Dr. McDade-Ngutter is a Health Program Specialist at the NIH Division of Nutrition Research Coordination. Both are members of the NIH Prebiotic and Probiotic Workgroup, which was originally created and led by the DNRC.

Q: Why was the formation of the NIH Prebiotic and Probiotic Workgroup necessary?
A: Dr. McDade-Ngutter - The Prebiotic and Probiotic Working Group (PPWG) was necessary to help facilitate opportunities for collaboration amongst the NIH Institutes and Centers (ICs) in the area of prebiotics and probiotics. The task of advancing pre- and probiotic research, which is the major goal of PPWG, requires a trans-NIH approach because this task is too great for one IC to tackle alone. The PPWG also meets regularly and keeps ICs abreast of all activities occurring in pre- and probiotics within NIH.

Q: Why is there an increased interest in probiotic research?
A: Dr. McDade-Ngutter- The increased interest in probiotics has been overwhelming and is likely attributed to the explosion of products referred to as “probiotic” that are widely available to consumers, and the health implications associated with their use. In addition, it is important to note that the launching of the Human Microbiome Project has had a profound impact on expanding the field of probiotics and will help scientists determine the mechanisms by which probiotics alter the gastrointestinal microbiota and effect human health. Learn more at http://commonfund.nih.gov/hmp/overview.aspx

Q: How important are partnerships and collaborations in advancing the probiotic research field?
A: Dr. McDade-Ngutter - Partnerships and collaborations are essential in closing some of the research gaps associated with probiotic research. It is widely recognized within the scientific community that collaborations and interactions amongst multiple scientists from various disciplines are necessary to gain an understanding of the complexities associated with probiotics in regards to their potential therapeutic uses and their relationship to the human microbiota.

Q: What are some of the challenges and barriers associated with probiotic research?
A: Dr. Duffy - In elucidating and substantiating health benefits of probiotic organisms, standardization methods based on high throughput sequencing and validation technologies are needed to demonstrate functional effects, biogenic properties, and specific biomarker activity. Modeling approaches and in vivo studies are needed to further substantiate how probiotic microbial metabolisms that make available by-products within the human ecosystem may be exploited to influence both the local and global structure of the microbiome. In human studies, given the heterogeneity of probiotic products, ensuring strain specific identity of probiotic organisms utilizing molecular techniques and in vivo validation, inclusion of product quality assessments and standards, rigorous trial design and consideration of regulatory assessment of safety and efficacy are critical to interpreting results.

Q: What was learned from the NIH/FDA sponsored AHRQ Evidence Safety report on Probiotics?
A: Dr. Duffy - There is a lack of assessment and systematic reporting of adverse events in probiotic intervention studies, and interventions are poorly documented. The available evidence in RCTs does not indicate an increased risk; however, rare adverse events are difficult to assess, and despite the substantial number of publications, the current literature is not well equipped to answer questions on the safety of probiotic interventions with confidence.

Q: What are some of the future needs in regards to probiotic research?
A: Dr. Duffy - Continuing to frame probiotics and human microbiome studies in a broad ecological paradigm will be  key to determining which traditional and novel species and strains promote health and well-being and are potentially of interest in biotherapeutic applications. Enhancing collaboration between teams of probiotics and human microbiome investigators, including experts from genomics and proteomics sciences, microbial ecology, molecular epidemiology, computational biology, immunology, biochemistry, nutrition, the physical and clinical sciences is paramount to advancing structure function studies focused on understanding the potential role of probiotics in promoting  metabolic function, including energy harvest from food and nutrient status, immune and cognitive function.