The Alberta BLOOM Clinical Research Study
Alberta BLOOM is a major research initiative at the University of Calgary aiming to discover how the maternal and infant microbiotas – all of the microbes living in and on the human body – impact infant and child health. By engaging mothers in biomedical research, Alberta BLOOM makes them active partners in the development of evidence-based policies and interventions that empower women to make healthy choices for their bodies and their babies.
Ecology of the Early Life Microbiome
A central goal of the Arrieta lab is to advance our ecological understandings of the early life gut microbiome, as this is fundamental to generating meaningful progress in health outcome-related microbiome research. The microbiome is a complex, multi-kingdom ecosystem, however, most research to date has focused only on characterizing the composition and functional role of bacteria. This provides an incomplete portrayal of the complex ecological dynamics occurring both within the gut and in relation to host physiological processes. Research from our lab has shown that bacteria and fungi are engaged in several symbiotic relationships, including in relation to immune responses, although much remains to be elucidated in understanding these interactions. The Arrieta lab continuously seeks to better characterize interkingdom dynamics occurring within the gut microbiome and understand their varied influences on the development and function of host physiological systems.
The Microbiome in Premature Infants
The Arrieta lab co-leads a prospective, longitudinal birth cohort study of premature infants born in Calgary called the Alberta BLOOM Study. This study follows premature infants from birth to three years of age, collecting comprehensive biological and clinical data that enables us to examine microbiome development during this period through a number of lenses. Given colonization patterns of the premature infant gut microbiome are known to differ from term-born infants, our goal is to better understand how these early alterations may impact infant development and long-term health outcomes, and to determine whether microbiome-based therapeutics may be employed to improve health outcomes in this population.
The Early Life Microbiome in Asthma Development
Asthma is one of the most common immune-mediated diseases affecting children and adults worldwide. Asthma is a complex condition that develops by a combination of both environmental and genetic factors. Amongst the many environmental factors that influence asthma incidence, early-life alterations to the gut microbiome are strongly associated with asthma susceptibility in children. Data from diverse population-based studies repeatedly show that factors such as birth via Caesarian (C-section), exclusive formula feeding, urban (vs. farm) living, prenatal and neonatal use of antibiotics, among others also known to directly influence the composition and function of the gut microbiome, increase the risk of children for being diagnosed with asthma by school age. The Arrieta lab aims to characterize how various environmental factors impact the microbiome and the specific microbial signatures that may predispose infants to asthma.
The Mycobiome in Early Life
The continuous advances in the microbiome field have allowed researches go beyond investigating just the bacterial players. The Arrieta lab has a strong focus on studying the mycobiome, and fungi are emerging as important members of the microbiome, though as this a fairly new avenue of study, it is not well characterized. We are interested in determining the composition and how environmental factors alter the gut mycobiome. With a combination of clinical and translational studies, we are determining how the mycobiome changes following antibiotic treatment in infants, and how these alterations influence susceptibility to immune-mediated diseases in mice.
The Microbiome and Colonization Resistance
The Arrieta lab’s interest in the microbiome also extends past early life to the microbiome’s role in metabolism, immune function and colonization resistance.
It is known that certain microbiome metabolites, such as SCFAs, can limit some pathogen’s ability to infect their hosts, and the Arrieta lab, along with some fantastic collaborators, is investigating the role of some novel microbiome-produced small aromatic molecules (MPSAMs). The effect of these molecules on colonization resistance against and virulence factors of Salmonella and EPEC infection, as well as their role in regulating host immune and metabolic functions is currently being investigated.
The Microbiome and Obesity
It has been previously established that the microbiome plays a crucial role in host metabolism and metabolic development. Additionally, the immune system, which has also been found to be regulated by the microbiome, has been implicated in the metabolic inflammation that accompanies obesity. While the role of bacterial commensals has been extensively investigated, the fungal population (mycobiome) remains understudied in this context. For this reason, the Arrieta lab aims to take a multi-kingdom approach to explore how commensal microbes modulate host metabolism as well as the immunological consequences of this relationship. We also plan to determine how the microbiome can be harnessed for therapeutic benefit in a metabolic context.
The Microbiome and Stress
The gut microbiome and the brain communicate bidirectionally via several host- and microbially-derived signaling mechanisms, forming the microbiome-gut-brain axis. This includes via the hypothalamic-pituitary-adrenal (HPA) axis, which is the principal regulator of the stress response in the body through the release of glucocorticoids such as cortisol. The microbiome has been causally implicated in HPA axis programming in early life in rodents, however, understandings in humans remain limited. Given the gut microbiome and the brain undergo periods of significant development in parallel in early life, and the microbiome-gut-brain axis is increasingly recognized as a key mechanism by which the microbiome influences host development and health outcomes, our lab seeks to better understand this relationship through both translational and clinical studies.