Leaky Gut syndrome
Leaky Gut and the use of pro-biotics.
A large body of literature now describes the phenomenon known as "leaky gut," a syndrome characterized by abnormal permeability of the intestines to potentially toxic or antigenic materials. Inflammatory bowel disease, alcoholism, rheumatic conditions involving the gut, allergic disorders, and a variety of other problems appear to be associated with abnormal gut permeability.
Lactobacillus GG: Unique "Native" Bacterium in Human GI Tract Lactobacilli constitute a major part of the microflora throughout the gastrointestinal tract. These bacteria have been proposed as candidate probiotic microorganisms to reinforce the barrier effect in the gut. Consumption of probiotic bacteria can alleviate intestinal inflammation, normalize increased intestinal permeability, and strengthen the intestine's immunologic barrier function.
Lactobacillus GG is a bacterium that occurs naturally in the human digestive tract. This strain of bacteria was first isolated by two Boston scientists, Professors Sherwood Gorbach and Barry Goldin, who were searching for a strain of lactobacillus that could colonize the human intestine and thereby exert the beneficial effects which Metchnikoff had hoped to produce by his yogurt cultures. As guides for their research, Gorbach and Goldin established a number of criteria which they believed their ideal probiotic candidate should satisfy. The bacterium would be: 1) be of human origin; 2) capable of attaching to human intestinal (epithelial) cells and colonizing the gut to prevent competition from invading pathogens; 3) resistant to acid and bile, able to survive transit from the stomach to the intestines; 4) exhibit beneficial, health-promoting activity in the host system; and 5) exhibit a high degree of safety.
Written by Nancy LeGendre, Ph.D. in Analytical Chemistry from MIT and mother of two autistic children
Our understanding of the physiology of autism has grown considerably in the past year and especially since our daughter, Lilly's endoscopy in Oct. '98. Aside from providing the first ever medical treatment for autism, secretin (and Victoria Beck) has turned the world of autism on their heads precisely because the focus for treatment has shifted from the realm of the brain to the realm of the gut. The secretin story, along with recent gut pathology data on over 100 autistic children in England (Andrew Wakefield), provides direct evidence that gut "insult" is an early and necessary event in autism.
This is a revolutionary direction for the world of autism. Until the Beck's persevered to bring their personal story forward, gut issues for autistic children were merely a footnote in the thousands of histories reported by parents and physicians, albeit often a messy footnote. Autistic children have long been described as having chronic and severe gastrointestinal issues including strange bacterial, viral and parasitic infections not seen in the general population. These unusual infections were ascribed to the fact that the kids ate nonfood items such as dirt and/or the children had self-limited, unhealthy diets leading to dysregulation and infection. When a child's gut issues manifested as constipation, parents were told that their autistic kids were simply displaying anal retentive behaviors... this even as the child vomited daily (based on personal experience).
A focus on gut issues in autism is medically and scientifically revolutionary but not without precedence to many hundreds of parents raising autistic spectrum children. Bernard Rimland, and the Defeat Autism Now! (DAN!) doctors along with parents, have long held that autism has a biological basis. The presence of opiate peptides (opioids) in the urine of autistic children led Panksepp and Reichelt and others to suggest that incompletely digested peptides of dietary origin had also made their way into the brains of autistics. Parents have reported significant improvement in their child's autistic behaviors by removing offending foodstuffs (primarily casein and gluten). Hence began the shift from a brain focus (opioids) to a gut/diet focus. Efforts to treat autistics with opiate antagonists such as naltrexate have met with uneven success. This is consistent with what we know about receptor subclasses. An array of opioids likely bind multiple brain receptor subclasses (mu, delta, gamma), while naltrexate works exclusively on the mu receptors.
How then can we pull together the various pieces of the autism puzzle into a coherent picture with the gut at it's center? There still exists a "primary event of unknown etiology".... a phrase that many parents chant in their sleep. Most individuals connected with autism feel comfortable claiming that there are multiple etiologies. This allows investigators to remain focused on their individual and different theories for this complex phenomenological syndrome ranging from environmental insult to vaccination/ autoimmune to genetics to encephalitic origin. Whatever the original insult, we know that multiple systems are affected including the endocrine system, the immune system and the central nervous system. And all of these systems talk with the gut. Gut injury is central to the pathology and hence, central to recovery.
Once the gut has sustained injury, digestion is disrupted and opiate peptides begin to accumulate. Incomplete digestion coupled with increased gut permeability (leaky gut) and a breach in the blood-brain barrier complete the picture. High levels of brain opioids can account for both the behaviors and physiology of autism. The latter include body temperature dysregulation, breath rate, pain sensation, sensory perception and thirst dysregulation (many autistics consume large volumes of liquids). While these basic autonomic functions are not the usual measures of autism (diagnostic criteria), most recognize these features of dysregulation in their autistic children.
So, what is the take home message? If you know what caused the original insult in your child, you would obviously try to correct that problem if possible... and warn other parents of, for example, the potential damage to an immature immune system in vaccination (i.e. never vaccinate a sick child). However, since the damage is likely begun, the proactive parent must seek treatment to relieve damage where it occurs. Gut damage may very well require dietary intervention (i.e. a gluten-free, casein-free diet). Other things which we know heal the gut include secretin, zinc supplementation, digestive enzyme supplementation and pepcid (Famotidine). There is still much work to do to understand how these factors work in every individual child. We still do not fully understand the role of the endocrine system, the immune system or, even neurotransmitters (i.e. elevated plasma serotonin) in this puzzle. Accepting that gut injury and healing can supersede brain injury in investigating treatment options for our autistic kids may very well be a first and necessary step.