Public Defence: Carina Madelen Saunders

MD Carina Madelen Saunders at Institute of Clinical Medicine will be defending the thesis “Diet and gut microbiome in early life a potential pathway for atopic disease development?” for the degree of PhD (Philosophiae Doctor).

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Photo: Åsne Rambøll Hillestad, UiO

Due to copyright issues, an electronic copy of the thesis must be ordered from the faculty. For the faculty to have time to process the order, the order must be received by the faculty at the latest 2 days before the public defence. Orders received later than 2 days before the defence will not be processed. After the public defence, please address any inquiries regarding the thesis to the candidate.

Trial Lecture – time and place

See Trial Lecture.

Adjudication committee

  • First opponent: Professor Christina West, Umeå University, Sweden
  • Second opponent: Associate Professor Martin Sørensen, UiT The Arctic University of Norway
  • Third member and chair of the evaluation committee: Professor Johannes Espolin Roksund Hov, University of Oslo

Chair of the Defence

Professor Lars Eide, University of Oslo

Principal Supervisor

Professor Karin Cecilie Lødrup Carlsen, University of Oslo

Summary

The rise in immune-mediated illnesses, such as atopic dermatitis, is linked to changes in the infant microbiome, influenced by maternal and infant diets. Through fermentation of dietary fibers, gut microbes produce short-chain fatty acids (SCFAs) like butyrate, which have anti-inflammatory properties and may impact disease development.

The aim was to assess maternal and infant diets, their impact on the infant gut microbiome and explore the effect of butyrate on atopic dermatitis development in infancy.

The thesis used data from the PreventADALL study, a randomized controlled interventional birth cohort study enrolling 2397 mother-child pairs antenatally in Norway and Sweden between 2014-17. Children randomized to food intervention were introduced to complementary foods from 3 months of age. Gut microbiome and short-chain fatty acids were analysed from fecal samples in the pregnant mother, and at birth, 3-, 6- and 12 months of infant age. Atopic dermatitis was clinically assessed at regular intervals in infancy.

Maternal diet in pregnancy showed consumption of red meat, salt, saturated fats alcohol, and coffee higher than national recommendations, and inadequate intake of essential micronutrients (folate, iron, selenium, calcium, vitamin D, iodine). Introducing complementary foods before 6 months did not lead to earlier breast-feeding cessation, and increased diet diversity in infancy. Gut microbiota composition changed from birth to 12 months, and butyrate increased 4-fold from 6 to 12 months. Breastfeeding was associated with bacterial taxonomy at 3, but not 6 and 12 months of age, while the time of complementary food introduction was not associated with microbiota.

Bacterial networks Eubacterium rectale and Faecalibacterium prausnitzii were identified as key bacteria responsible for butyrate production in the infant gut, whereas Ruminococcus gnavus and its associated network of bacteria were linked to lower butyrate levels. High butyrate levels in the infant’s gut at 12 months were associated with reduced development of atopic dermatitis.

These findings point to the role of early life diet in developing a healthy gut microbiota with implications for immune-mediated disease development.

Additional information

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Published June 5, 2024 7:31 AM - Last modified June 17, 2024 12:58 PM