Browsing by Author "Knight, Rob"

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    A gut-derived metabolite alters brain activity and anxiety behaviour in mice
    (Springer Nature, 2022) Needham, Brittany D.; Funabashi, Masanori; Adame, Mark D.; Wang, Zhuo; Boktor, Joseph C.; Haney, Jillian; Wu, Wei-Li; Rabut, Claire; Ladinsky, Mark S.; Hwang, Son-Jong; Guo, Yumei; Zhu, Qiyun; Griffiths, Jessica A.; Knight, Rob; Bjorkman, Pamela J.; Shapiro, Mikhail G.; Geschwind, Daniel H.; Holschneider, Daniel P.; Fischbach, Michael A.; Mazmanian, Sarkis K.; Anatomy, Cell Biology and Physiology, School of Medicine
    Integration of sensory and molecular inputs from the environment shapes animal behaviour. A major site of exposure to environmental molecules is the gastrointestinal tract, in which dietary components are chemically transformed by the microbiota1 and gut-derived metabolites are disseminated to all organs, including the brain2. In mice, the gut microbiota impacts behaviour3, modulates neurotransmitter production in the gut and brain4,5, and influences brain development and myelination patterns6,7. The mechanisms that mediate the gut-brain interactions remain poorly defined, although they broadly involve humoral or neuronal connections. We previously reported that the levels of the microbial metabolite 4-ethylphenyl sulfate (4EPS) were increased in a mouse model of atypical neurodevelopment8. Here we identified biosynthetic genes from the gut microbiome that mediate the conversion of dietary tyrosine to 4-ethylphenol (4EP), and bioengineered gut bacteria to selectively produce 4EPS in mice. 4EPS entered the brain and was associated with changes in region-specific activity and functional connectivity. Gene expression signatures revealed altered oligodendrocyte function in the brain, and 4EPS impaired oligodendrocyte maturation in mice and decreased oligodendrocyte-neuron interactions in ex vivo brain cultures. Mice colonized with 4EP-producing bacteria exhibited reduced myelination of neuronal axons. Altered myelination dynamics in the brain have been associated with behavioural outcomes7,9-14. Accordingly, we observed that mice exposed to 4EPS displayed anxiety-like behaviours, and pharmacological treatments that promote oligodendrocyte differentiation prevented the behavioural effects of 4EPS. These findings reveal that a gut-derived molecule influences complex behaviours in mice through effects on oligodendrocyte function and myelin patterning in the brain.
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    Fecal Microbiota Transplantation Is Highly Effective in Real-World Practice: Initial Results From the FMT National Registry
    (Elsevier, 2021-01) Kelly, Colleen R.; Yen, Eugene F.; Grinspan, Ari M.; Kahn, Stacy A.; Atreja, Ashish; Lewis, James D.; Moore, Thomas A.; Rubin, David T.; Kim, Alison M.; Serra, Sonya; Nersesova, Yanina; Fredell, Lydia; Hunsicker, Dea; McDonald, Daniel; Knight, Rob; Allegretti, Jessica R.; Pekow, Joel; Absah, Imad; Hsu, Ronald; Vincent, Jennifer; Khanna, Sahil; Tangen, Lyn; Crawford, Carl V.; Mattar, Mark C.; Chen, Lea Ann; Fischer, Monika; Arsenescu, Razvan I.; Feuerstadt, Paul; Goldstein, Jonathan; Kerman, David; Ehrlich, Adam C.; Wu, Gary D.; Laine, Loren; Medicine, School of Medicine
    Background & Aims Fecal microbiota transplantation (FMT) is used commonly for treatment of Clostridioides difficile infections (CDIs), although prospective safety data are limited and real-world FMT practice and outcomes are not well described. The FMT National Registry was designed to assess FMT methods and both safety and effectiveness outcomes from North American FMT providers. Methods Patients undergoing FMT in clinical practices across North America were eligible. Participating investigators enter de-identified data into an online platform, including FMT protocol, baseline patient characteristics, CDI cure and recurrence, and short and long-term safety outcomes. Results Of the first 259 participants enrolled at 20 sites, 222 had completed short-term follow-up at 1 month and 123 had follow-up to 6 months; 171 (66%) were female. All FMTs were done for CDI and 249 (96%) used an unknown donor (eg, stool bank). One-month cure occurred in 200 patients (90%); of these, 197 (98%) received only 1 FMT. Among 112 patients with initial cure who were followed to 6 months, 4 (4%) had CDI recurrence. Severe symptoms reported within 1-month of FMT included diarrhea (n = 5 [2%]) and abdominal pain (n = 4 [2%]); 3 patients (1%) had hospitalizations possibly related to FMT. At 6 months, new diagnoses of irritable bowel syndrome were made in 2 patients (1%) and inflammatory bowel disease in 2 patients (1%). Conclusions This prospective real-world study demonstrated high effectiveness of FMT for CDI with a good safety profile. Assessment of new conditions at long-term follow-up is planned as this registry grows and will be important for determining the full safety profile of FMT.
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    Multi-level analysis of the gut–brain axis shows autism spectrum disorder-associated molecular and microbial profiles
    (Springer Nature, 2023) Morton, James T.; Jin, Dong-Min; Mills, Robert H.; Shao, Yan; Rahman, Gibraan; McDonald, Daniel; Zhu, Qiyun; Balaban, Metin; Jiang, Yueyu; Cantrell, Kalen; Gonzalez, Antonio; Carmel, Julie; Frankiensztajn, Linoy Mia; Martin-Brevet, Sandra; Berding, Kirsten; Needham, Brittany D.; Zurita, María Fernanda; David, Maude; Averina, Olga V.; Kovtun, Alexey S.; Noto, Antonio; Mussap, Michele; Wang, Mingbang; Frank, Daniel N.; Li, Ellen; Zhou, Wenhao; Fanos, Vassilios; Danilenko, Valery N.; Wall, Dennis P.; Cárdenas, Paúl; Baldeón, Manuel E.; Jacquemont, Sébastien; Koren, Omry; Elliott, Evan; Xavier, Ramnik J.; Mazmanian, Sarkis K.; Knight, Rob; Gilbert, Jack A.; Donovan, Sharon M.; Lawley, Trevor D.; Carpenter, Bob; Bonneau, Richard; Taroncher-Oldenburg, Gaspar; Anatomy, Cell Biology and Physiology, School of Medicine
    Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by heterogeneous cognitive, behavioral and communication impairments. Disruption of the gut–brain axis (GBA) has been implicated in ASD although with limited reproducibility across studies. In this study, we developed a Bayesian differential ranking algorithm to identify ASD-associated molecular and taxa profiles across 10 cross-sectional microbiome datasets and 15 other datasets, including dietary patterns, metabolomics, cytokine profiles and human brain gene expression profiles. We found a functional architecture along the GBA that correlates with heterogeneity of ASD phenotypes, and it is characterized by ASD-associated amino acid, carbohydrate and lipid profiles predominantly encoded by microbial species in the genera Prevotella, Bifidobacterium, Desulfovibrio and Bacteroides and correlates with brain gene expression changes, restrictive dietary patterns and pro-inflammatory cytokine profiles. The functional architecture revealed in age-matched and sex-matched cohorts is not present in sibling-matched cohorts. We also show a strong association between temporal changes in microbiome composition and ASD phenotypes. In summary, we propose a framework to leverage multi-omic datasets from well-defined cohorts and investigate how the GBA influences ASD.