University of B.C. researchers have conducted a groundbreaking study that reveals a significant connection between micronutrient deficiencies and changes in gut microbiomes, potentially contributing to the global issue of rising antibiotic resistance. The study, published in Nature Microbiology, sheds light on the far-reaching implications of nutrient deficiencies in early life.

The research team focused on the impact of deficiencies in essential micronutrients, such as vitamin A, B12, folate, iron, and zinc, on the composition of the gut microbiome in weanling male mice. Over a 28-day period, the mice were subjected to a diet deficient in these vital micronutrients. Fecal samples were collected at the beginning and end of the study period for metagenomics sequencing and analysis.

The findings were startling: the mice with micronutrient deficiencies exhibited significant alterations in their gut microbiomes. Particularly concerning was the expansion of bacteria and fungi known to be opportunistic pathogens, posing potential health risks. Notably, the mice also showed a higher enrichment of genes associated with antibiotic resistance, suggesting that nutrient deficiencies may create an environment conducive to the development of antibiotic resistance.

Dr. Paula Littlejohn, a postdoctoral research fellow at UBC's department of medical genetics and department of pediatrics, as well as the BC Children's Hospital Research Institute, emphasized the implications of this discovery. She explained, "Micronutrient deficiency has been an overlooked factor in the conversation about global antibiotic resistance. Our study suggests that nutrient deficiencies can make the gut environment more susceptible to antibiotic resistance, a major worldwide health concern."

The presence of antibiotic resistance genes in bacteria is a natural defense mechanism, but certain factors, including nutrient stress or antibiotic pressure, can increase their prevalence. This poses a dangerous threat, potentially rendering potent antibiotics ineffective and causing common infections to become deadly.

While antibiotic resistance is often attributed to the misuse and overuse of antibiotics, the UBC study highlights the significant role of "hidden hunger" caused by micronutrient deficiencies. As Dr. Littlejohn stated, "Globally, around 340 million children under five suffer from multiple micronutrient deficiencies, which not only affect their growth but also significantly alter their gut microbiomes." This is especially concerning as these children are often prescribed antibiotics to treat malnutrition-related illnesses, potentially further increasing their susceptibility to antibiotic resistance.

The study stresses the urgent need for comprehensive strategies to address undernutrition and its impact on health. It emphasizes that addressing micronutrient deficiencies is not only crucial for combating malnutrition but also plays a vital role in tackling the global problem of antibiotic resistance.

The research conducted by the UBC team brings valuable insights into the complex relationship between micronutrients, gut microbiomes, and antibiotic resistance. Going forward, further research and action in this field could pave the way for novel approaches to combat antibiotic resistance and improve overall health outcomes.

Reference:
Paula T. Littlejohn et al, Multiple micronutrient deficiencies in early life cause multi-kingdom alterations in the gut microbiome and intrinsic antibiotic resistance genes in mice, Nature Microbiology (2023). DOI: 10.1038/s41564-023-01519-3.