From cells to anxiety

Thanks to brain tissue research, scientists now know how cells in the amygdala form, connect, and how this changes with age.  But does that explain behavioral or neurological features in autism?  Last week, Dr. Inna Fishman from SDSU examined connections in and out of the amygdala in children and adolescents in autism, in a different study but the same age range as when cellular changes in the amygdala are seen.  Strikingly, the brain connections to regions outside the amygdala follow a similar pattern at a similar time, which may explain functioning, autism severity and anxiety in adolescents with autism.   Also this week, while autism is a spectrum, it’s on a spectrum with other neurodevelopmental disorders like ADHD.  Just like in autism, there are individuals who are not diagnosed with ADHD until adulthood.  But these adults show signs of autism as children.  This is similar to autism, where symptoms are there but may not manifest until later in life.

 

https://www.ncbi.nlm.nih.gov/pubmed/30274651

https://www.ncbi.nlm.nih.gov/pubmed/30338854

Here’s to understanding why people with autism have anxiety in adolescence

Using resources from the Autism BrainNet, researchers from UC Davis show specific brain changes in an area called the amygdala in autism.  The amygdala is associated with fear, emotion and anxiety in people with autism.  But because they can look at the brain directly,  the actual number of neurons in the amygdala can be counted not just in one individual, but in over 50 individuals across ages 2 to 50.  This remarkable study showed that too much activity in the amygdala early may lead to impaired function later on.  This could be caused by too many neurons which are present early on in life in people with ASD, and reflected by fewer neurons later on in life.  These difference can only be detected through looking directly at brain tissue.  To learn more, register for the Autism BrainNet at www.takesbrains.org/signup.

Here is a link to the paper:  http://www.pnas.org/content/early/2018/03/19/1801912115.long

Dr. Avino will be answering questions about this paper on a Q&A on April 9, 2018 – please register here:  https://register.gotowebinar.com/register/7051754498195523073

What is the microbiome and why should families with ASD care?

This week’s ASF Podcast is a special interview with Dr. Gil Sharon from CalTech, who studies the microbiome in animal models and potential link to ASD.  The microbiome is the full community of bacteria that live in our bodies and outnumber cells 10-1. They can affect the genome directly and they can respond to environmental factors which means they may be a site for important gene x environment interactions in autism.  Some people with ASD, especially those with gastrointestinal problems, show alterations in the microbiome and more and more scientists are starting to incorporate studying this complex system into their research.  Most importantly, new research is suggesting potential for probiotic therapies to not only treat GI symptoms, but also core autism symptoms.  If you like the podcast, Dr. Sharon has provided a list of resources which can provide more detail:

Interventions in mice –

Hsiao, E.Y., McBride, S.W., Hsien, S., Sharon, G., Hyde, E.R., McCue, T., Codelli, J.A., Chow, J., Reisman, S.E., Petrosino, J.F., et al. (2013). Microbiota modulate behavioral and physiological abnormalities associated with neurodevelopmental disorders. Cell 155, 1451–1463.

Buffington, S.A., Di Prisco, G.V., Auchtung, T.A., Ajami, N.J., Petrosino, J.F., and Costa-Mattioli, M. (2016). Microbial Reconstitution Reverses Maternal Diet-Induced Social and Synaptic Deficits in Offspring. Cell 165, 1762–1775.

Intervention in humans –

Kang, D.-W., Adams, J.B., Gregory, A.C., Borody, T., Chittick, L., Fasano, A., Khoruts, A., Geis, E., Maldonado, J., McDonough-Means, S., et al. (2017). Microbiota Transfer Therapy alters gut ecosystem and improves gastrointestinal and autism symptoms: an open-label study. Microbiome 5, 10.

Microbiome profiling –

Gondalia, S.V., Palombo, E.A., Knowles, S.R., Cox, S.B., Meyer, D., and Austin, D.W. (2012). Molecular characterisation of gastrointestinal microbiota of children with autism (with and without gastrointestinal dysfunction) and their neurotypical siblings. Autism Res. 5, 419–427.

De Angelis, M., Piccolo, M., Vannini, L., Siragusa, S., De Giacomo, A., Serrazzanetti, D.I., Cristofori, F., Guerzoni, M.E., Gobbetti, M., and Francavilla, R. (2013). Fecal microbiota and metabolome of children with autism and pervasive developmental disorder not otherwise specified. PLoS One 8, e76993.

Son, J.S., Zheng, L.J., Rowehl, L.M., Tian, X., Zhang, Y., Zhu, W., Litcher-Kelly, L., Gadow, K.D., Gathungu, G., Robertson, C.E., et al. (2015). Comparison of Fecal Microbiota in Children with Autism Spectrum Disorders and Neurotypical Siblings in the Simons Simplex Collection. PLoS One 10, e0137725.

 

The Benefits of Being and Older Father

Advanced paternal age is one of the more replicated risk factors for autism – but maybe not autism as it as seen as a disorder.  Recent studies by Mount Sinai School of Medicine and Kings College of London show in both animal models and in epidemiological studies that advanced age in fathers is associated with the “active but odd” phenotype and PDD NOS.  In people, older (but not “old”) age in fathers led to increased IQ and social aloofness that led to higher academic achievement.  Is this autism?  Or just a subtype of autism where the outcomes are adaptive rather than maladaptive?  There are lots of questions about the nature of autism in these findings.

When can you see autism in the brain?

This week the Infant Brain Imaging Study, or IBIS, published it’s 2nd study on the emergence of changes in the brains of individuals with autism.  While red flags for autism can be seen early, a diagnosis of autism is not typically made until after 24 months of age. Using a baby sibling research design, scientists showed increases in the size of certain areas of the brain between 6-12 months.  This opens up opportunities for even earlier diagnosis of ASD in the future.   Also, a group at Stanford shows the emergence and disappearance of co-morbid symptoms in autism, such as epilepsy, schizophrenia and ADHD, which are dependent on sex and age.  Together, these studies show that autism begins very very early and symptoms and behavioral and biological features change over time.