Nearly 1 in 5 individuals in the U.S. suffers from a mental disorder, yet the underlying causes for many psychiatric illnesses are largely unknown, and effective treatments are lacking. Recent preclinical studies have revealed striking effects of microbiome manipulations on complex, higher-order behaviors, including anxiety, sociability, cognition and emotional behavior. Moreover, molecular assessments reveal a key role for the microbiome in modulating neurochemical metabolism, global brain gene expression, microglial activation and blood brain barrier permeability. Driven by these findings, recent examination of patients suffering from mental disorders, including schizophrenia and depression, reveals dysbiosis of the microbiota. Altogether, these findings raise the interesting prospect of whether changes in the microbiome can contribute to, or be used to modify, symptoms of brain and behavioral disorders.
Current Research Projects
The laboratory of Dr. Elaine Hsiao at UCLA is studying microbiome-gut-brain effects on symptoms of neurodevelopmental disorders and molecular signaling between gut microbes and the nervous system. Dr. Hsiao’s previous work in this area demonstrated that postnatal modification of the commensal microbiota improves GI and behavioral symptoms in mouse models of genetic and environmental risk factors for autism. This work is the first to demonstrate that the microbiota regulates stereotypic, sensorimotor and communicative behavior, and to further reveal that microbe-mediated changes in levels of neuroactive metabolites impact behavior. A separate study conducted by the Hsiao lab identified a particular bacterial consortium from the human and mouse microbiome that reversibly modulates host serotonin biosynthesis and ameliorates serotonin-related disease phenotypes in mice. The group is following up on both these areas, studying how gene-environment interactions involving the microbiota affect disorders, like epilepsy and autism, and how microbes influence neurochemical levels and neuronal activation.
- Yano JM, Yu K, Donaldson G, Shastri G, Ma L, Ann P, Nagler C, Ismagilov RF, Mazmanian SK, Hsiao EY (2015) Indigenous bacteria from the gut microbiota regulate host serotonin biosynthesis. Cell, 161:264-76.
- Hsiao EY, McBride SW, Hsien S, Sharon G, Hyde ER, McCue T, Codelli JA, Chow J, Reisman SE, Petrosino JF, Patterson PH*, Mazmanian SK* (2013) The microbiota modulates behavioral and physiological abnormalities associated with neurodevelopmental disorders. Cell, 155:1451-1463.
- Hsiao EY, McBride SW, Chow J, Mazmanian SK, Patterson PH (2012) Modeling an autism risk factor in mice leads to permanent immune dysregulation. PNAS 109:12776-81
Helen Lavretsky, MDProfessor in Residence, Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at UCLA
Dr. Helen Lavretsky is the Geriatric Psychiatrist at UCLA with research interests in treatment and prevention of mood and cognitive disorders of aging. Her studies have already shown that mind-body exercise such as yoga and Tai Chi can help to reduce depression and cognitive decline in aging adults and in stressed caregivers. Current research studies offer participation in Tai Chi and yoga studies, as well as pharmacological studies for geriatric depression and mild cognitive impairment.
Dr. Lavretsky aims to investigate the role of microbiota in late life mood and cognitive disorders by comparing microbiome composition in those with and without mood and cognitive symptoms, and to develop interventions targeting microbiota and wellness for prevention of mood disorders and cognitive decline in older adults.
Relevant Recent Publications
- Lee S.M., Lavretsky H. “Microbiota and disorders of aging” IN: Complementary and Integrative Therapies for Mental Health and Aging. Eds: Lavretsky, Sajatovic, Reynolds, Oxford University Press [in press].