Scientist - News - 25-06-2009:

Probiotics plus prebiotics: more than 1+1
Beintema, Nienke

A combination of pre- and probiotics is sometimes more effective than any of the components by themselves, concludes PhD candidate Bastiaan Schouten. He recently published an article on this issue in the Journal of Nutrition, and will defend his thesis this November.

Cow’s milk allergy is the most common allergy in infants. Around 3 to 5 percent of babies in Western countries are diagnosed with this condition. There is currently no cure. There is, however, increasing evidence that pre- and probiotics can play a role in preventing the development of allergies. One of the people working on this issue is Bastiaan Schouten, PhD candidate at the department of Pharmacology and Pathophysiology at Utrecht University, which has a strategic alliance with Danone Research – Centre for Specialised Nutrition.
Schouten is particularly interested in the combination of the pre- and probiotics, called synbiotics. "There have been some studies into the effect of Immunofortis^®," he explains, "which is a specific combination of certain oligosaccharides. These studies showed quite uniform results: Immunofortis^® decreases the incidence of atopic dermatitis in infants, it has a positive effect on the immunoglobulin profile in children under the age of six months, and it decreases the incidence of infections at one and two years of age."

Mouse model
The added value of his own research, as he explains, is that it includes probiotics in this kind of studies. "There have been several studies into synbiotic effects," he says, "but they differed strongly in their methodology, which makes it difficult to compare and generalize their results."
Schouten’s research indicates that there is indeed an added value in the combination of pre- and probiotics. "This line of research is still relatively new," he says, "and therefore we largely use mouse models to analyze the effect of various interventions. We know, however, that there are certain basic similarities between the immune systems of mice and humans, which allow us to translate the basic results to the human situation."
Schouten used mice that were made allergic to cow’s milk. "We used several parameters to measure the allergic reaction upon allergen challenge, including an assessment of shock symptoms, the swelling in their ears, and immunological parameters."

Mechanism
Schouten found that the combination of prebiotics and the probiotic Bifidobacterium breve M16-V had a better modulating effect on the allergic reaction than each of these components individually. "Both shock and swelling were significantly more reduced when pre- and probiotics were administered together," he notes, "although this was not represented in any significant changes in the ‘bad’ immunoglobulins IgE and IgG1. However, the levels of ‘beneficial’ immunoglobulins, IgA and IgG2a, which bind to cow’s milk proteins and thus neutralize their action, were clearly increased."
Schouten notes that more research is needed into other strains of probiotics that may be suitable candidates for synbiotic treatments. So far, B. breve M16-V was used because of its proven effect in various other studies. "And finally," says Schouten, "we’d like to look at more detail at the underlying mechanisms. Why exactly is the combination more effective? Research into the function of regulatory T cells might shed more light on that."

More information:
Article in the Journal of Nutrition (May 2009)