Mainz University Medical Center scientists have hit upon a series of observations involving nanoparticulates and its relationship to the microbiome-host balance.
According to professor David McClements from the University of Massachusetts, Its influence on human health gives rise to the idea of dietary nanoparticles and the need to understand its role, potential risks and promotion of health.
“Prior to our studies, nobody really looked whether and how nano-additives directly influence the gastrointestinal flora," added professor Roland Stauber from the Mainz University Medical Center.
"Hence, we studied at a wide range of technical nanoparticles with clearly defined properties in order to mimic what happens to currently used or potential future nanosized food additives.
“By simulating the journey of particles through the different environments of the digestive tract in the laboratory, we found that the all tested nanomaterials were indeed able to bind to bacteria,” he added.
Nanoparticles to deliver nutrients
The food industry currently engineers nanoparticles (NPs) to be used as nutrient delivery systems or antimicrobial agents and may thus be ingested as part of nanoenabled foods and beverages.
Present day thinking suggests exposure to ingested NPs, even for a short time, may modify the composition and diversity of the gut microbiome and thus influence health and well-being.
Researchers led by the University Medical Center of Johannes Gutenberg University Mainz (JGU) began looking at synthetic NPs and bacterial models with a focus on their interactions from analytical to in situ to in vitro.
The NPs and microparticles used were made from silica, polymer, metal oxide and carbon all varied in size, fluorescence and surface modifications.
The team also used colorectal epithelial (Caco2), gastric cancer (AGS, MKN-28), and human monocytic leukaemia (THP-1) cell lines.
The researchers noted that nanoparticle-bound microorganisms were less efficiently recognized by the immune system, which may lead to increased inflammatory responses.
However, 'nano-food' showed beneficial effects. In cell culture models, silica nanoparticles inhibited the infectivity of Helicobacter pylori, which is considered to be one of the main agents involved in gastric cancer.
‘Nanoparticulates are already omnipresent’
'It was puzzling that we were able to also isolate naturally occurring nanoparticles from food, like beer, which showed similar effects,” said Dr Stauber.
“Nanoparticles in our daily food are not just those added deliberately but can also be generated naturally during preparation. Nanoparticulates are already omnipresent."
The team believe the findings may open up avenues to more effective NP-based systems for the treatment of GI infections.
Additionally, environmental factors, such as dietary components and micronutrients as well as the GI microbiota have previously been shown to affect the balance between H. pylori’s role as a commensal or a pathogen.
“We showed that NPs naturally present in food as well as synthetic nanosized food additives may impact the bacterial life cycle,” the study said.
“Hence, one may speculate that during evolution not only soluble chemicals but also (nano) particulates may have contributed to shaping the microbiome as well as its interaction with the human host.”
Probiotic food supplements
Speculating further, the team thought there may be possibilities to exploit natural or synthetic nanosized food additives in the future, to achieve positive “side-effects” by shaping the microbiome and/or by inhibiting enteric pathogens, such as H. pylori.
“The insights of the study will allow to derive strategies for developing and utilizing synthetic or natural nanoparticles to modulate the microbiome as beneficial ingredients in functional foods,” added Dr Stauber.
"The challenge is to identify nanoparticles that fit the desired purpose, perhaps even as probiotic food supplements in the future."
Source: NPJ Science of Food
Published online: doi.org/10.1038/s41538-018-0030-8
“Nanosized food additives impact beneficial and pathogenic bacteria in the human gut: a simulated gastrointestinal study.”
Authors: Svenja Siemer, Angelina Hahlbrock, Cecilia Vallet, David Julian McClements, Jan Balszuweit, Jens Voskuhl, Dominic Docter, Silja Wessler, Shirley Knauer, Dana Westmeier & Roland Stauber
