Dr. Francis Collins
New Chief Executive Officer for All of Us
Posted on by Dr. Francis Collins
Could A Gut-Brain Connection Help Explain Autism?
Posted on by Dr. Francis Collins
You might think nutrient-sensing cells in the human gastrointestinal (GI) tract would have no connection whatsoever to autism spectrum disorder (ASD). But if Diego Bohórquez’s “big idea” is correct, these GI cells, called neuropods, could one day help to provide a direct link into understanding and treating some aspects of autism and other brain disorders.
Bohórquez, a researcher at Duke University, Durham, NC, recently discovered that cells in the intestine, previously known for their hormone-releasing ability, form extensions similar to neurons. He also found that those extensions connect to nerve fibers in the gut, which relay signals to the vagus nerve and onward to the brain. In fact, he found that those signals reach the brain in milliseconds [1].
Bohórquez has dedicated his lab to studying this direct, high-speed hookup between gut and brain and its impact on nutrient sensing, eating, and other essential behaviors. Now, with support from a 2019 NIH Director’s New Innovator Award, he will also explore the potential for treating autism and other brain disorders with drugs that act on the gut.
Bohórquez became interested in autism and its possible link to the gut-brain connection after a chance encounter with Geraldine Dawson, director of the Duke Center for Autism and Brain Development. Dawson mentioned that autism typically affects multiple organ systems.
With further reading, he discovered that kids with autism frequently cope with GI issues, including bowel inflammation, abdominal pain, constipation, and/or diarrhea [2]. They often also show unusual food-related behaviors, such as being extremely picky eaters. But his curiosity was especially piqued by evidence that certain gut microbes can influence abnormal behaviors in mice that model autism.
With his New Innovator Award, Bohórquez will study neuropods and the gut-brain connection in a mouse model of autism. Using the tools of optogenetics, which make it possible to activate cells with light, he’ll also see whether autism-like symptoms in mice can be altered or alleviated by controlling neuropods in the gut. Those symptoms include anxiety, repetitive behaviors, and lack of interest in interacting with other mice. He’ll also explore changes in the animals’ eating habits.
In another line of study, he will take advantage of intestinal tissue samples collected from people with autism. He’ll use those tissues to grow and then examine miniature intestinal “organoids,” looking for possible evidence that those from people with autism are different from others.
For the millions of people now living with autism, no truly effective drug therapies are available to help to manage the condition and its many behavioral and bodily symptoms. Bohórquez hopes one day to change that with drugs that act safely on the gut. In the meantime, he and his fellow “GASTRONAUTS” look forward to making some important and fascinating discoveries in the relatively uncharted territory where the gut meets the brain.
References:
[1] A gut-brain neural circuit for nutrient sensory transduction. Kaelberer MM, Buchanan KL, Klein ME, Barth BB, Montoya MM, Shen X, Bohórquez DV. Science. 2018 Sep 21;361(6408).
[2] Association of maternal report of infant and toddler gastrointestinal symptoms with autism: evidence from a prospective birth cohort. Bresnahan M, Hornig M, Schultz AF, Gunnes N, Hirtz D, Lie KK, Magnus P, Reichborn-Kjennerud T, Roth C, Schjølberg S, Stoltenberg C, Surén P, Susser E, Lipkin WI. JAMA Psychiatry. 2015 May;72(5):466-474.
Links:
Autism Spectrum Disorder (National Institute of Mental Health/NIH)
Bohórquez Lab (Duke University, Durham, NC)
Bohórquez Project Information (NIH RePORTER)
NIH Director’s New Innovator Award (Common Fund)
NIH Support: Common Fund; National Institute of Mental Health
Insurance Status Helps Explain Racial Disparities in Cancer Diagnosis
Posted on by Dr. Francis Collins
Women have the best odds of surviving breast cancer if their disease is caught at an early stage, when treatments are most likely to succeed. Major strides have been made in the early detection of breast cancer in recent years. But not all populations have benefited equally, with racial and ethnic minorities still more likely to be diagnosed with later-stage breast cancer than non-Hispanic whites. Given that recent observance of Martin Luther King Day, I thought that it would be particularly appropriate to address a leading example of health disparities.
A new NIH-funded study of more than 175,000 U.S. women diagnosed with breast cancer from 2010-2016 has found that nearly half of the troubling disparity in breast cancer detection can be traced to lack of adequate health insurance. The findings suggest that improving insurance coverage may help to increase early detection and thereby reduce the disproportionate number of breast cancer deaths among minority women.
Naomi Ko, Boston University School of Medicine, has had a long interest in understanding the cancer disparities she witnesses first-hand in her work as a medical oncologist. For the study published in JAMA Oncology, she teamed up with epidemiologist Gregory Calip, University of Illinois Cancer Center, Chicago [1]. Their goal was to get beyond documenting disparities in breast cancer and take advantage of available data to begin to get at why such disparities exist and what to do about them.
Disparities in breast cancer outcomes surely stem from a complicated mix of factors, including socioeconomic factors, culture, diet, stress, environment, and biology. Ko and Calip focused their attention on insurance, thinking of it as a factor that society can collectively modify.
Many earlier studies had shown a link between insurance and cancer outcomes [2]. It also stood to reason that broad differences among racial and ethnic minorities in their access to adequate insurance might drive some of the observed cancer disparities. But, Ko and Calip asked, just how big a factor was it?
To find out, they looked to the NIH’s Surveillance Epidemiology, and End Results (SEER) Program, run by the National Cancer Institute. The SEER Program is an authoritative source of information on cancer incidence and survival in the United States.
The researchers focused their attention on 177,075 women of various races and ethnicities, ages 40 to 64. All had been diagnosed with invasive stage I to III breast cancer between 2010 and 2016.
The researchers found that a higher proportion of women receiving Medicaid or who were uninsured received a diagnosis of advanced stage III breast cancer compared with women with health insurance. Black, American Indian, Alaskan Native, and Hispanic women also had higher odds of receiving a late-stage diagnosis.
Overall, their sophisticated statistical analyses traced up to 47 percent of the racial/ethnic differences in the risk of locally advanced disease to differences in health insurance. Such late-stage diagnoses and the more extensive treatment regimens that go with them are clearly devastating for women with breast cancer and their families. But, the researchers note, they’re also costly for society, due to lost productivity and escalating treatment costs by stage of breast cancer.
These researchers surely aren’t alone in recognizing the benefit of early detection. Last week, an independent panel convened by NIH called for enhanced research to assess and explore how to reduce health disparities that lead to unequal access to health care and clinical services that help prevent disease.
References:
[1] Association of Insurance Status and Racial Disparities With the Detection of Early-Stage Breast Cancer. Ko NY, Hong S, Winn RA, Calip GS. JAMA Oncol. 2020 Jan 9.
[2] The relation between health insurance coverage and clinical outcomes among women with breast cancer. Ayanian JZ, Kohler BA, Abe T, Epstein AM. N Engl J Med. 1993 Jul 29;329(5):326-31.
[3] Cancer Stat Facts: Female Breast Cancer. National Cancer Institute Surveillance, Epidemiology, and End Results Program.
Links:
Cancer Disparities (National Cancer Institute/NIH)
Breast Cancer (National Cancer Institute/NIH)
Naomi Ko (Boston University)
Gregory Calip (University of Illinois Cancer Center, Chicago)
NIH Support: National Center for Advancing Translational Sciences; National Cancer Institute; National Institute on Minority Health and Health Disparities
NIH HEAL Investigator Meeting
Posted on by Dr. Francis Collins
Time Well Spent in North Carolina
Posted on by Dr. Francis Collins
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