New ways to treat illness by targeting therapies at microbes living in the human gut were discussed at the latest instalment of the Grand Rounds lecture series at Weill Cornell Medicine-Qatar (WCM-Q).

Ghizlane Bendriss, PhD, Lecturer in Biology at WCM-Q, gave a presentation that explained the latest research into treatments focused on gut microbiota for conditions such as diabetes, obesity, chronic clostridium difficile infections, ulcerative colitis and inflammatory bowel disease, among others. The lecture also discussed the possible link between gut microbiota and autism.

The gut microbiota is made up of trillions of microorganisms, including bacteria, viruses, archaea, and fungi. These microorganisms are vital to human health, playing an important role in modulating metabolism, immunity and brain function. It is estimated that each human hosts their own unique population of around 100 trillion microbial cells, far more than the number of human cells each person possesses.

Imbalances between beneficial and harmful microorganisms lead to a state called dysbiosis, which is often characterised by an inflammatory immune response. Research has shown that dysbiosis is observed in most diseases and disorders, leading physicians and scientists to speculate that interventions to reestablish a healthy microbiota equilibrium might be effective treatment for a number of conditions.

Gut Microbiota and Obesity

Gut Microbiata
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Dr Bendriss explained that recent research on mice demonstrated that gut microbiota appear to play a significant role in causing obesity. Other studies showed that fecal implants could help cure long-standing clostridium difficile infections. Dr Bendriss herself is currently leading a study on ‘The Role of Human Gut Microbiota in Autism Spectrum Disorders and Inflammatory Bowel Disorders’.

Explaining the link between gut microbiota and the brain, she said that bacteria in the gut are involved in processing food; processing of the food makes metabolites, such as short-chain fatty acids and others. These metabolites trigger the release of hormones, some of which act on the brain where they can influence things like satiety, among many other things.

Dr Bendriss said the metabolites also trigger the release of hormones that act on the pancreas, which affects insulin secretion, suggesting a link between the gut microbiota and diabetes.

With more than 100 trillion microorganisms in the human body, more than the number of human cells, we can imagine that they have a significant effect on physiology, metabolism, immunity and disease. This is therefore a very exciting area for further research that has a lot of potential for improving human health in many different ways.’

The lecture was accredited locally by the Qatar Council for Healthcare Practitioners-Accreditation Department (QCHP-AD) and by the Accreditation Council for Continuing Medical Education (ACCME). Visit for updates and more information about the Grand Rounds series.