Dysbiosis

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Dysbiosis (also called dysbacteriosis) refers to microbial imbalance on or inside the body.[1] Dysbiosis is most commonly reported as a condition in the digestive tract. It has been associated with illnesses, such as inflammatory bowel disease[3],[4][5] chronic fatigue syndrome,[6] obesity,[7][8] cancer[9][10] and colitis.[11]

Microbial colonies found on or in the body are normally benign or beneficial. These beneficial and appropriately sized microbial colonies carry out a series of helpful and necessary functions, such as aiding in digestion.[12] They also protect the body from the penetration of pathogenic microbes. These beneficial microbial colonies compete with each other for space and resources and outnumber human cells by a factor 10:1.[13]

The term "dysbiosis" is not a standardized medical term. Apparently similar concepts are also described as "microbial imbalance", "bacterial imbalance", or "increased levels of harmful bacteria and reduced levels of the beneficial bacteria".[14]

Causes[edit]

Dysbiosis may be caused by such diverse things as repeated and inappropriate antibiotic exposure,[15] alcohol misuse,[16][17] or inappropriate diet.[18]

Effects[edit]

When this balance is disturbed, these colonies exhibit a decreased ability to check each other's growth, which can then lead to overgrowth of one or more of the disturbed colonies which may further damage some of the other smaller beneficial ones in a vicious cycle. As more beneficial colonies are damaged, making the imbalance more pronounced, more overgrowth issues occur because the damaged colonies are less able to check the growth of the overgrowing ones. If this goes unchecked long enough, a pervasive and chronic imbalance between colonies will set in, which ultimately minimizes the beneficial nature of these colonies as a whole.

Microbial colonies also excrete many different types of waste byproducts. Using different waste removal mechanisms, under normal circumstances the body effectively manages these byproducts with little or no trouble. Unfortunately, oversized and inappropriately large colonies, due to their increased numbers, excrete increased amounts of these byproducts. As the amount of microbial byproducts increases, the higher waste byproducts levels can overburden the body's waste removal mechanisms.

It is the combination of these two negative outcomes that causes many of the negative health symptoms observed when dysbiosis is present.

See also[edit]

Notes and references[edit]

  1. ^ Tamboli, CP; Neut, C; Desreumaux, P; Colombel, JF (2004). "Dysbiosis in inflammatory bowel disease". Gut 53: 1–4. PMC 1773911. 
  2. ^ Seksik, P. (2010). "Gut microbiota and IBD". Gastroentérologie Clinique et Biologique 34 (Suppl 1): S44–51. doi:10.1016/S0399-8320(10)70020-8. PMID 20889004. 
  3. ^ Imbalance in the intestinal microbiome may be associated with bowel inflammation.[2]
  4. ^ Marteau, Philippe (2009). "Bacterial Flora in Inflammatory Bowel Disease". Digestive Diseases 27: 99–103. doi:10.1159/000268128. PMID 20203504. 
  5. ^ Lepage, P.; Leclerc, M. C.; Joossens, M.; Mondot, S.; Blottiere, H. M.; Raes, J.; Ehrlich, D.; Dore, J. (23 April 2012). "A metagenomic insight into our gut's microbiome". Gut 62 (1): 146–58. doi:10.1136/gutjnl-2011-301805. PMID 22525886. 
  6. ^ Lakhan, Shaheen E; Kirchgessner, Annette (2010). "Gut inflammation in chronic fatigue syndrome". Nutrition & Metabolism 7: 79. doi:10.1186/1743-7075-7-79. PMC 2964729. PMID 20939923. 
  7. ^ Turnbaugh, Peter J; Ruth E Ley; Michael A Mahowald; Vincent Magrini; Elaine R Mardis; Jeffrey I Gordon (2006-12-21). "An obesity-associated gut microbiome with increased capacity for energy harvest". Nature 444 (7122): 1027–1031. doi:10.1038/nature05414. ISSN 1476-4687. PMID 17183312. 
  8. ^ Turnbaugh, Peter J.; Micah Hamady, Tanya Yatsunenko, Brandi L. Cantarel, Alexis Duncan, Ruth E. Ley, Mitchell L. Sogin, William J. Jones, Bruce A. Roe, Jason P. Affourtit, Michael Egholm, Bernard Henrissat, Andrew C. Heath, Rob Knight, Jeffrey I. Gordon (2009-01-22). "A core gut microbiome in obese and lean twins". Nature 457 (7228): 480–484. doi:10.1038/nature07540. ISSN 0028-0836. PMC 2677729. PMID 19043404. Retrieved 2014-03-25. 
  9. ^ Castellarin, Mauro; René L Warren, J Douglas Freeman, Lisa Dreolini, Martin Krzywinski, Jaclyn Strauss, Rebecca Barnes, Peter Watson, Emma Allen-Vercoe, Richard A Moore, Robert A Holt (2012-02). "Fusobacterium nucleatum infection is prevalent in human colorectal carcinoma". Genome research 22 (2): 299–306. doi:10.1101/gr.126516.111. ISSN 1549-5469. PMC 3266037. PMID 22009989. 
  10. ^ Kostic, Aleksandar D; Dirk Gevers, Chandra Sekhar Pedamallu, Monia Michaud, Fujiko Duke, Ashlee M Earl, Akinyemi I Ojesina, Joonil Jung, Adam J Bass, Josep Tabernero, José Baselga, Chen Liu, Ramesh A Shivdasani, Shuji Ogino, Bruce W Birren, Curtis Huttenhower, Wendy S Garrett, Matthew Meyerson (2012-02). "Genomic analysis identifies association of Fusobacterium with colorectal carcinoma". Genome research 22 (2): 292–298. doi:10.1101/gr.126573.111. ISSN 1549-5469. PMC 3266036. PMID 22009990. 
  11. ^ Mazmanian, Sarkis K (2008-04). "Capsular polysaccharides of symbiotic bacteria modulate immune responses during experimental colitis". Journal of pediatric gastroenterology and nutrition. 46 Suppl 1: –11–12. doi:10.1097/01.mpg.0000313824.70971.a7. ISSN 1536-4801. PMID 18354314. 
  12. ^ Kau, Andrew L.; Ahern, Philip P.; Griffin, Nicholas W.; Goodman, Andrew L.; Gordon, Jeffrey I. (15 June 2011). "Human nutrition, the gut microbiome and the immune system". Nature 474 (7351): 327–336. doi:10.1038/nature10213. PMC 3298082. PMID 21677749. 
  13. ^ Xuan, Caiyun; Jaime M. Shamonki; Alice Chung; Maggie L. DiNome; Maureen Chung; Peter A. Sieling; Delphine J. Lee (2014-01-08). "Microbial Dysbiosis Is Associated with Human Breast Cancer". PLoS ONE 9 (1). doi:10.1371/journal.pone.0083744. ISSN 1932-6203. PMC 3885448. PMID 24421902. Retrieved 2014-03-24. 
  14. ^ http://news.harvard.edu/gazette/story/2014/03/imbalance-in-microbial-population-found-in-crohns-patients/
  15. ^ Hawrelak, Jason A.; Myers, Stephen P. (2004). "The causes of intestinal dysbiosis: a review". Alternative medicine review 9 (2): 180–97. PMID 15253677. 
  16. ^ Yan, Arthur W.; E. Fouts, Derrick; Brandl, Johannes; Stärkel, Peter; Torralba, Manolito; Schott, Eckart; Tsukamoto, Hide; E. Nelson, Karen et al. (2011). "Enteric dysbiosis associated with a mouse model of alcoholic liver disease". Hepatology 53 (1): 96–105. doi:10.1002/hep.24018. PMC 3059122. PMID 21254165. 
  17. ^ Mutlu, Ece; Keshavarzian, Ali; Engen, Phillip; Forsyth, Christopher B.; Sikaroodi, Masoumeh; Gillevet, Patrick (2009). "Intestinal Dysbiosis: A Possible Mechanism of Alcohol-Induced Endotoxemia and Alcoholic Steatohepatitis in Rats". Alcoholism: Clinical and Experimental Research 33 (10): 1836–46. doi:10.1111/j.1530-0277.2009.01022.x. 
  18. ^ Chan, Yee Kwan; Estaki, Mehrbod; Gibson, Deanna L. (2013). "Clinical consequences of diet-induced dysbiosis". Ann. Nutr. Metab. 63 (suppl2): 28–40. doi:10.1159/000354902. PMID 24217034. 

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