Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis
The ecosystem of the gut microbiota consists of diverse intestinal species with multiple metabolic and immunologic activities and it is closely connected with the intestinal epithelia and mucosal immune response, with which it builds a complex barrier against intestinal pathogenic bacteria. The micr...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2019-08-01
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| Series: | Frontiers in Microbiology |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fmicb.2019.01676/full |
| _version_ | 1818278642497617920 |
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| author | Simona Iacob Simona Iacob Diana Gabriela Iacob |
| author_facet | Simona Iacob Simona Iacob Diana Gabriela Iacob |
| author_sort | Simona Iacob |
| collection | DOAJ |
| description | The ecosystem of the gut microbiota consists of diverse intestinal species with multiple metabolic and immunologic activities and it is closely connected with the intestinal epithelia and mucosal immune response, with which it builds a complex barrier against intestinal pathogenic bacteria. The microbiota ensures the integrity of the gut barrier through multiple mechanisms, either by releasing antibacterial molecules (bacteriocins) and anti-inflammatory short-chain fatty acids or by activating essential cell receptors for the immune response. Experimental studies have confirmed the role of the intestinal microbiota in the epigenetic modulation of the gut barrier through posttranslational histone modifications and regulatory mechanisms induced by epithelial miRNA in the epithelial lumen. Any quantitative or functional changes of the intestinal microbiota, referred to as dysbiosis, alter the immune response, decrease epithelial permeability and destabilize intestinal homeostasis. Consequently, the overgrowth of pathobionts (Staphylococcus, Pseudomonas, and Escherichia coli) favors intestinal translocations with Gram negative bacteria or their endotoxins and could trigger sepsis, septic shock, secondary peritonitis, or various intestinal infections. Intestinal infections also induce epithelial lesions and perpetuate the risk of bacterial translocation and dysbiosis through epithelial ischemia and pro-inflammatory cytokines. Furthermore, the decline of protective anaerobic bacteria (Bifidobacterium and Lactobacillus) and inadequate release of immune modulators (such as butyrate) affects the release of antimicrobial peptides, de-represses microbial virulence factors and alters the innate immune response. As a result, intestinal germs modulate liver pathology and represent a common etiology of infections in HIV immunosuppressed patients. Antibiotic and antiretroviral treatments also promote intestinal dysbiosis, followed by the selection of resistant germs which could later become a source of infections. The current article addresses the strong correlations between the intestinal barrier and the microbiota and discusses the role of dysbiosis in destabilizing the intestinal barrier and promoting infectious diseases. |
| first_indexed | 2024-12-12T23:20:41Z |
| format | Article |
| id | doaj.art-21b7a5b1fca44a39bd4e9b4289f3a780 |
| institution | Directory Open Access Journal |
| issn | 1664-302X |
| language | English |
| last_indexed | 2024-12-12T23:20:41Z |
| publishDate | 2019-08-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Microbiology |
| spelling | doaj.art-21b7a5b1fca44a39bd4e9b4289f3a7802022-12-22T00:08:17ZengFrontiers Media S.A.Frontiers in Microbiology1664-302X2019-08-011010.3389/fmicb.2019.01676448283Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: DysbiosisSimona Iacob0Simona Iacob1Diana Gabriela Iacob2Infectious Diseases Department, “Carol Davila” University of Medicine and Pharmacy, Bucharest, RomaniaNational Institute of Infectious Diseases “Prof. Dr. Matei Balş”, Bucharest, RomaniaInfectious Diseases Department, “Carol Davila” University of Medicine and Pharmacy, Bucharest, RomaniaThe ecosystem of the gut microbiota consists of diverse intestinal species with multiple metabolic and immunologic activities and it is closely connected with the intestinal epithelia and mucosal immune response, with which it builds a complex barrier against intestinal pathogenic bacteria. The microbiota ensures the integrity of the gut barrier through multiple mechanisms, either by releasing antibacterial molecules (bacteriocins) and anti-inflammatory short-chain fatty acids or by activating essential cell receptors for the immune response. Experimental studies have confirmed the role of the intestinal microbiota in the epigenetic modulation of the gut barrier through posttranslational histone modifications and regulatory mechanisms induced by epithelial miRNA in the epithelial lumen. Any quantitative or functional changes of the intestinal microbiota, referred to as dysbiosis, alter the immune response, decrease epithelial permeability and destabilize intestinal homeostasis. Consequently, the overgrowth of pathobionts (Staphylococcus, Pseudomonas, and Escherichia coli) favors intestinal translocations with Gram negative bacteria or their endotoxins and could trigger sepsis, septic shock, secondary peritonitis, or various intestinal infections. Intestinal infections also induce epithelial lesions and perpetuate the risk of bacterial translocation and dysbiosis through epithelial ischemia and pro-inflammatory cytokines. Furthermore, the decline of protective anaerobic bacteria (Bifidobacterium and Lactobacillus) and inadequate release of immune modulators (such as butyrate) affects the release of antimicrobial peptides, de-represses microbial virulence factors and alters the innate immune response. As a result, intestinal germs modulate liver pathology and represent a common etiology of infections in HIV immunosuppressed patients. Antibiotic and antiretroviral treatments also promote intestinal dysbiosis, followed by the selection of resistant germs which could later become a source of infections. The current article addresses the strong correlations between the intestinal barrier and the microbiota and discusses the role of dysbiosis in destabilizing the intestinal barrier and promoting infectious diseases.https://www.frontiersin.org/article/10.3389/fmicb.2019.01676/fulldysbiosisintestinal microbiotaepigenetic modulationshort chain fatty acidsimmunitysepsis |
| spellingShingle | Simona Iacob Simona Iacob Diana Gabriela Iacob Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis Frontiers in Microbiology dysbiosis intestinal microbiota epigenetic modulation short chain fatty acids immunity sepsis |
| title | Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis |
| title_full | Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis |
| title_fullStr | Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis |
| title_full_unstemmed | Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis |
| title_short | Infectious Threats, the Intestinal Barrier, and Its Trojan Horse: Dysbiosis |
| title_sort | infectious threats the intestinal barrier and its trojan horse dysbiosis |
| topic | dysbiosis intestinal microbiota epigenetic modulation short chain fatty acids immunity sepsis |
| url | https://www.frontiersin.org/article/10.3389/fmicb.2019.01676/full |
| work_keys_str_mv | AT simonaiacob infectiousthreatstheintestinalbarrieranditstrojanhorsedysbiosis AT simonaiacob infectiousthreatstheintestinalbarrieranditstrojanhorsedysbiosis AT dianagabrielaiacob infectiousthreatstheintestinalbarrieranditstrojanhorsedysbiosis |