Leaky gut
Leaky gut and ALS[edit]
"Emerging evidence has demonstrated that intestinal homeostasis and the microbiome play essential roles in neurological diseases, such as Parkinson's disease. ... We examined the gut of an ALS mouse model, G93A, which expresses mutant superoxide dismutase (SOD1(G93A)), and discovered a damaged tight junction structure and increased permeability with a significant reduction in the expression levels of tight junction protein ZO-1 and the adherens junction protein E-cadherin. Furthermore, our data demonstrated increased numbers of abnormal Paneth cells in the intestine of G93A mice. Paneth cells are specialized intestinal epithelial cells that can sense microbes and secrete antimicrobial peptides, thus playing key roles in host innate immune responses and shaping the gut microbiome. A decreased level of the antimicrobial peptides defensin 5 alpha was indeed found in the ALS intestine. These changes were associated with a shifted profile of the intestinal microbiome, including reduced levels of Butyrivibrio Fibrisolvens, Escherichia coli, and Fermicus, in G93A mice. The relative abundance of bacteria was shifted in G93A mice compared to wild-type mice. Principal coordinate analysis indicated a difference in fecal microbial communities between ALS and wild-type mice. Taken together, our study suggests a potential novel role of the intestinal epithelium and microbiome in the progression of ALS.[1]
"Here we present evidence that intestinal dysfunction and dysbiosis may actively contribute to ALS pathophysiology... The G93A mice show abnormal intestinal microbiome and damaged tight junctions before ALS disease onset. The mice were given 2% butyrate, a natural bacterial product, in the drinking water. ... In mice fed with butyrate, intestinal microbial homeostasis was restored, gut integrity was improved, and life span was prolonged compared with those in control mice. At the cellular level, abnormal Paneth cells-specialized intestinal epithelial cells that regulate the host-bacterial interactions-were significantly decreased in the ALS mice treated with butyrate. In both ALS mice and intestinal epithelial cells cultured from humans, butyrate treatment was associated with decreased aggregation of the G93A superoxide dismutase 1 mutated protein. ... The findings from this study highlight the complex role of the gut microbiome and intestinal epithelium in the progression of ALS and present butyrate as a potential therapeutic reagent for restoring ALS-related dysbiosis."[2]
References[edit]
- ↑ Wu et al.: Leaky intestine and impaired microbiome in an amyotrophic lateral sclerosis mouse model. Physiol Rep 2015;3:. PMID: 25847918. DOI. Emerging evidence has demonstrated that intestinal homeostasis and the microbiome play essential roles in neurological diseases, such as Parkinson's disease. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons and muscle atrophy. Currently, there is no effective treatment. Most patients die within 3-5 years due to respiratory paralysis. Although the death of motor neurons is a hallmark of ALS, other organs may also contribute to the disease progression. We examined the gut of an ALS mouse model, G93A, which expresses mutant superoxide dismutase (SOD1(G93A)), and discovered a damaged tight junction structure and increased permeability with a significant reduction in the expression levels of tight junction protein ZO-1 and the adherens junction protein E-cadherin. Furthermore, our data demonstrated increased numbers of abnormal Paneth cells in the intestine of G93A mice. Paneth cells are specialized intestinal epithelial cells that can sense microbes and secrete antimicrobial peptides, thus playing key roles in host innate immune responses and shaping the gut microbiome. A decreased level of the antimicrobial peptides defensin 5 alpha was indeed found in the ALS intestine. These changes were associated with a shifted profile of the intestinal microbiome, including reduced levels of Butyrivibrio Fibrisolvens, Escherichia coli, and Fermicus, in G93A mice. The relative abundance of bacteria was shifted in G93A mice compared to wild-type mice. Principal coordinate analysis indicated a difference in fecal microbial communities between ALS and wild-type mice. Taken together, our study suggests a potential novel role of the intestinal epithelium and microbiome in the progression of ALS.
- ↑ Zhang et al.: Target Intestinal Microbiota to Alleviate Disease Progression in Amyotrophic Lateral Sclerosis. Clin Ther 2017;39:322-336. PMID: 28129947. DOI. PURPOSE: Emerging evidence has demonstrated that gut microbiome plays essential roles in the pathogenesis of human diseases in distal organs. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons. Treatment with the only drug approved by the US Food and Drug Administration for use in ALS, riluzole, extends a patient׳s life span by only a few months. Thus, there is an urgent need to develop novel interventions that for alleviate disease progression and improve quality of life in patients with ALS. Here we present evidence that intestinal dysfunction and dysbiosis may actively contribute to ALS pathophysiology. METHODS: We used G93A transgenic mice as a model of human ALS. The G93A mice show abnormal intestinal microbiome and damaged tight junctions before ALS disease onset. The mice were given 2% butyrate, a natural bacterial product, in the drinking water. RESULTS: In mice fed with butyrate, intestinal microbial homeostasis was restored, gut integrity was improved, and life span was prolonged compared with those in control mice. At the cellular level, abnormal Paneth cells-specialized intestinal epithelial cells that regulate the host-bacterial interactions-were significantly decreased in the ALS mice treated with butyrate. In both ALS mice and intestinal epithelial cells cultured from humans, butyrate treatment was associated with decreased aggregation of the G93A superoxide dismutase 1 mutated protein. IMPLICATIONS: The findings from this study highlight the complex role of the gut microbiome and intestinal epithelium in the progression of ALS and present butyrate as a potential therapeutic reagent for restoring ALS-related dysbiosis.
