A new review demonstrates the role of the gut microbiome in autism spectrum disorders

Posted on Fri, Jun 23, 2017 @ 06:52 AM


Autism spectrum disorder (ASD) has an unclear cause but is associated with various genetic, neurologic, metabolic, and immunologic factors. Although there is no definitive treatment, gastrointestinal symptoms are common in patients with autism. Such patients who present GI symptoms may show significant behavioral manifestations, including anxiety, self-injury and aggression.

In a recent review in Frontiers in Cellular Neuroscience, researchers review the bidirectional interactions between the central nervous system (CNS) and the gastrointestinal tract via the brain-gut axis, and the role of the gut microbiota in the CNS and ASD.

This review of over 150 papers on ASD and gut bacteria found that, since the 1960s, researchers have been reporting on the association between the composition of gut microbiome and autistic behavior. It highlights many studies which have shown that restoring a healthy balance in gut bacteria can help ASD symptoms.

Research demonstrates that the gut microbiota is associated with ASD symptoms (directly or indirectly), in part by altering the immune system and metabolism. Studies show a higher percentage of intestinal permeability in ASD patients, resulting in a higher antigenic load from the gastrointestinal tract. These inflammatory cytokines are present in the circulation and cross the blood-brain barrier. Alterations in the composition of the gut microbiota and their metabolic products are commonly observed in patients with ASD. For example, lipopolysaccharide (LPS) is increased in the serum of ASD patients and is associated with impaired social behavioral scores.

In addition, the gut microbiome of children with ASD is less diverse with lower levels of Bifidobacterium and Firmicutes and higher levels of Lactobacillus, Clostridium, Bacteroidetes, Desulfovibrio, Caloramator and Sarcina. Also, children with autism who present gastrointestinal symptoms have lower abundances of the genera Prevotella, Coprococcus, and Veillonellaceae, and higher levels of the Clostridium histolyticum group. The reduction of Clostridium results in significant improvements with ASD symptoms.

Researchers found that Candida was twice as abundant in ASD. The dysbiosis seen in ASD results in the expansion of Candida, leading to further imbalance and an exacerbation in abnormal behaviors.

Early life events can alter the composition of the gut microbiome in ASD patients. These may include the overuse of antibiotics, maternal obesity and diabetes during pregnancy, how a baby is delivered, and if and how long the infant was breastfed. Keep in mind that a child under three years of age whose brain is at the height of development may have impaired neurodevelopment due to the presence of the metabolic products resulting from the dysbiosis and intestinal permeability.

As I stated earlier, at present, there is no definitive treatment or cure for ASD. However, there are certain diet and nutritional therapies that offer help, such as a gluten-free and casein-free (GFCF) diet. Many of these children have a dysbiosis and opportunistic infections; thus, it is essential to assess their gut health. As described, children with ASD have significantly different concentrations of certain bacteria in their stool compared to children without ASD. It is suspected that gut microbes can alter the levels of neurotransmitter-related metabolites, affecting the gut-to-brain communication and altering brain function.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

New study demonstrates sulforaphane helps to improve glucose control in patients with type 2 diabetes

Posted on Fri, Jun 16, 2017 @ 10:08 AM


According to a study published two days ago, researchers demonstrated that sulforaphane improves fasting glucose levels and decreases HbA1c levels in patients with type 2 diabetes.

Metabolic syndrome and insulin resistance are significant health care problems in the United States. Type 2 diabetes affects more than 300 million people, and up to 15% of patients cannot take the medication metformin because of kidney damage risks. As a result, researchers sought out to identify compounds that may inhibit disease-associated gene expression changes seen with type 2 diabetes.

The researchers constructed a signature for type 2 diabetes based on 50 genes, then used publically available expression datasets to screen 3,852 compounds for drugs that potentially reverse the disease. They demonstrated that sulforaphane reduced glucose production by liver cells growing in culture and altered liver gene expression away from a diseased state in diabetic rats.

Researchers then gave 97 patients with type 2 diabetes a concentrated broccoli sprout extract (BSE) for 12 weeks. As result, BSE reduced fasting glucose in patients with dysregulated type 2 diabetes but not in patients with well-regulated type 2 diabetes. They also observed an association between body mass index and BSE-induced change in HbA1c. There were significantly reduced levels of HbA1c after BSE treatment in obese patients with dysregulated type 2 diabetes. BSE was also more effective in lowering fasting blood glucose in patients with elevated triglyceride levels and in patients with high HOMA-IR. The BSE-induced reduction of HbA1c correlated with high fatty liver index.

These results demonstrate that sulforaphane reduces glucose production by NRF2 translocation and decreased expression of key gluconeogenetic enzymes and improves fasting glucose and HbA1c in obese patients with dysregulated type 2 diabetes. Sulforaphane reduces glucose production by mechanisms different than metformin and also protects against diabetic neuropathy, renal failure, and atherosclerosis due to its antioxidative effects.

There are several additional nutrients that can play a role in improving insulin signaling such as chromium, zinc, carnosine, benfotiamine, alpha lipoic acid, and inositol. Also, essential fatty acids should be consumed for overall health, but most individuals with insulin resistance are deficient. Fish oils improve insulin sensitivity and reduce inflammation.

While insulin resistance continues to be a major health issue in the US, it is preventable and reversible through lifestyle changes, exercise, stress management, and proper nutrition and supplements. Weight loss and exercise are considered among the best treatments for restoring the body’s ability to respond to insulin.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS