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Cell Host & Microbe Apr 2018The gut microbiota play important roles in lipid metabolism and absorption. However, the contribution of the small bowel microbiota of mammals to these diet-microbe...
The gut microbiota play important roles in lipid metabolism and absorption. However, the contribution of the small bowel microbiota of mammals to these diet-microbe interactions remains unclear. We determine that germ-free (GF) mice are resistant to diet-induced obesity and malabsorb fat with specifically impaired lipid digestion and absorption within the small intestine. Small bowel microbes are essential for host adaptation to dietary lipid changes by regulating gut epithelial processes involved in their digestion and absorption. In addition, GF mice conventionalized with high-fat diet-induced jejunal microbiota exhibit increased lipid absorption even when fed a low-fat diet. Conditioned media from specific bacterial strains directly upregulate lipid absorption genes in murine proximal small intestinal epithelial organoids. These findings indicate that proximal gut microbiota play key roles in host adaptability to dietary lipid variations through mechanisms involving both the digestive and absorptive phases and that these functions may contribute to conditions of over- and undernutrition.
Topics: Animals; Diet; Gastrointestinal Microbiome; Intestine, Small; Lipid Metabolism; Mice
PubMed: 29649441
DOI: 10.1016/j.chom.2018.03.011 -
International Journal of Molecular... May 2020Small intestinal bacterial overgrowth (SIBO) is a condition hallmarked by an increase in the concentration of colonic-type bacteria in the small bowel. Watery diarrhea,... (Review)
Review
Small intestinal bacterial overgrowth (SIBO) is a condition hallmarked by an increase in the concentration of colonic-type bacteria in the small bowel. Watery diarrhea, bloating, abdominal pain and distension are the most common clinical manifestations. Additionally, malnutrition and vitamin (B12, D, A, and E) as well as minerals (iron and calcium) deficiency may be present. SIBO may mask or worsen the history of some diseases (celiac disease, irritable bowel disease), may be more common in some extra-intestinal disorders (scleroderma, obesity), or could even represent a pathogenetic link with some diseases, in which a perturbation of intestinal microbiota may be involved. On these bases, we performed a review to explore the multiple links between SIBO and digestive and extra-intestinal diseases.
Topics: Animals; Blind Loop Syndrome; Disease; Humans; Intestine, Small
PubMed: 32429454
DOI: 10.3390/ijms21103531 -
Gut Microbes 2021Mucin-degrading bacteria are densely populated in the intestinal epithelium; however, their interaction with intestinal stem cells (ISCs) and their progeny have not been...
Mucin-degrading bacteria are densely populated in the intestinal epithelium; however, their interaction with intestinal stem cells (ISCs) and their progeny have not been elucidated. To determine whether mucin-degrading bacteria play a role in gut homeostasis, mice were treated with , a specialized species that degrades mucin. Administration of for 4 weeks accelerated the proliferation of Lgr5 ISCs and promoted the differentiation of Paneth cells and goblet cells in the small intestine (SI). We found similar effects of in the colon. The levels of acetic and propionic acids were higher in the cecal contents of -treated mice than in PBS-treated mice. SI organoids treated with cecal contents obtained from -treated mice were larger and could be diminished by treatment with G protein-coupled receptor (Gpr) 41/43 antagonists. Pre-treatment of mice with reduced gut damage caused by radiation and methotrexate. Further, a novel isotype of the strain was isolated from heathy human feces that showed enhanced function in intestinal epithelial regeneration. These findings suggest that mucin-degrading bacteria (e.g., ) may play a crucial role in promoting ISC-mediated epithelial development and contribute to intestinal homeostasis maintenance.
Topics: Akkermansia; Animals; Cell Differentiation; Cell Proliferation; Epithelial Cells; Fatty Acids, Volatile; Feces; Female; Gastrointestinal Microbiome; Homeostasis; Humans; Intestinal Mucosa; Intestine, Small; Methotrexate; Mice; Mice, Inbred C57BL; Mucins; Stem Cells; Wnt Signaling Pathway
PubMed: 33678130
DOI: 10.1080/19490976.2021.1892441 -
Annals of the Royal College of Surgeons... Oct 2020Intertwining of bowel loops to form a knot is very rare cause of intestinal obstruction. Among intestinal knots, ileoileal knotting is the most rare, with only a handful... (Review)
Review
INTRODUCTION
Intertwining of bowel loops to form a knot is very rare cause of intestinal obstruction. Among intestinal knots, ileoileal knotting is the most rare, with only a handful of cases reported in literature. We present a rare case of ileoileal knotting and review of small bowel knots. The aim of this review was to summarise the existing evidence on small bowel knots and to postulate the possible mechanisms for knotting.
METHODS
A systematic search was conducted for literature published up to December 2019 using MEDLINE, PubMed and Google Scholar databases, together with the references of the full-text articles retrieved. Papers with case reports of small bowel knots were considered to be eligible for inclusion in the review.
FINDINGS
A total of 14 case reports were evaluated. There was no clear predilection for age or sex. Mostly cases were from Asia and Africa with no cases from the West. The presenting complaints were abdominal pain (93%), vomiting (64%), abdominal distention (57 %) and obstipation (43%). The bowel was gangrenous in 78% of cases. All underwent exploration, with the majority requiring resection and anastomosis of the involved segment.
CONCLUSION
Ileoileal knotting is a very rare cause of intestinal obstruction. Possible mechanisms include loaded bowel with longer mesentery, vigorous peristalsis, single bulky meal, pregnancy and intussusception. The condition is extremely difficult to diagnose preoperatively and it is usually diagnosed intraoperatively. The standard of treatment is resection of gangrenous part and anastomosis.
Topics: Abdominal Pain; Adult; Aged; Aged, 80 and over; Female; Gangrene; Humans; Infant; Intestinal Obstruction; Intestinal Volvulus; Intestine, Small; Intussusception; Male; Middle Aged; Vomiting; Young Adult
PubMed: 32538120
DOI: 10.1308/rcsann.2020.0122 -
Cold Spring Harbor Perspectives in... Jan 2020The small intestine is the longest organ in the human body, spanning a length of ∼5 m and compartmentalized into three distinct regions with specific roles in... (Review)
Review
The small intestine is the longest organ in the human body, spanning a length of ∼5 m and compartmentalized into three distinct regions with specific roles in maintenance of comprehensive homeostasis. Along its length exists as a unique and independent system-called the enteric nervous system (ENS)-which coordinates the multitude of functions continuously around the clock. Yet, with so many vital roles played, the functions, relationships, and roles of the small intestine and ENS remain largely elusive. This fundamental hole in the physiology of the small intestine and ENS introduces a substantial number of challenges when attempting to create bioelectronic approaches for treatment of various disorders originating in the small intestine. Here, we review existing therapeutic options for modulating the small intestine, discuss fundamental gaps that must be addressed, and highlight novel methods and approaches to consider for development of bioelectronic approaches aiming to modulate the small intestine.
Topics: Animals; Enteric Nervous System; Gastrointestinal Microbiome; Homeostasis; Humans; Intestine, Small
PubMed: 30858329
DOI: 10.1101/cshperspect.a034355 -
FEMS Microbiology Reviews May 2023Growing evidence suggests the importance of the small intestinal bacteria in the diet-host-microbiota dialogue in various facets of health and disease. Yet, this body... (Review)
Review
Growing evidence suggests the importance of the small intestinal bacteria in the diet-host-microbiota dialogue in various facets of health and disease. Yet, this body site is still poorly explored and its ecology and mechanisms of interaction with the host are just starting to be unraveled. In this review, we describe the current knowledge on the small intestinal ecology, its composition and diversity, and how the intestinal bacteria in homeostatic conditions participate in nutrient digestion and absorption. We illustrate the importance of a controlled bacterial density and of the preservation of absorptive surface for the host's nutritional status. In particular, we discuss these aspects of the small intestinal environment in the framework of two disease conditions, namely small intestinal bacterial overgrowth (SIBO) and short bowel syndrome (SBS). We also detail in vivo, ex vivo, and in vitro models developed to simulate the small intestinal environment, some applied for (diet-)host-bacteria interaction studies. Lastly, we highlight recent technological, medical, and scientific advances applicable to investigate this complex and yet understudied body environment to broaden our knowledge in support of further progress in the medical practice, and to proceed towards the integration of the (small)intestinal bacteria in personalized therapeutic approaches.
Topics: Intestine, Small; Microbiota; Diet
PubMed: 37193669
DOI: 10.1093/femsre/fuad022 -
World Journal of Gastroenterology Aug 2014Spontaneous free perforation of the small intestine is uncommon, especially if there is no prior history of visceral trauma. However, free, even recurrent, perforation... (Review)
Review
Spontaneous free perforation of the small intestine is uncommon, especially if there is no prior history of visceral trauma. However, free, even recurrent, perforation may complicate a defined and established clinical disorder, such as Crohn's disease. In addition, free perforation may be the initial clinical presentation of an occult intestinal disorder, such as a lymphoma complicating celiac disease, causing diffuse peritonitis and an acute abdomen. Initial diagnosis of the precise cause may be difficult, but now has been aided by computerized tomographic imaging. The site of perforation may be helpful in defining a cause (e.g., ileal perforation in Crohn's disease, jejunal perforation in celiac disease, complicated by lymphoma or collagenous sprue). Urgent surgical intervention, however, is usually required for precise diagnosis and treatment. During evaluation, an expanding list of other possible causes should be considered, even after surgery, as subsequent management may be affected. Free perforation may not only complicate an established intestinal disorder, but also a new acute process (e.g., caused by different infectious agents) or a longstanding and unrecognized disorder (e.g., congenital, metabolic and vascular causes). Moreover, new endoscopic therapeutic and medical therapies, including use of emerging novel biological agents, have been complicated by intestinal perforation. Recent studies also support the hypothesis that perforation of the small intestine may be genetically-based with different mutations causing altered connective tissue structure, synthesis and repair.
Topics: Adult; Humans; Intestinal Perforation; Intestine, Small; Predictive Value of Tests; Prognosis; Recurrence; Risk Factors; Rupture, Spontaneous
PubMed: 25110427
DOI: 10.3748/wjg.v20.i29.9990 -
Physiological Research 2002Gastrointestinal motility is an integrated process including myoelectrical and contractile activity, tone, compliance and transit. The techniques for the assessment of... (Review)
Review
Gastrointestinal motility is an integrated process including myoelectrical and contractile activity, tone, compliance and transit. The techniques for the assessment of gastrointestinal motility are multiple and all have their advantages and disadvantages. In the case of suspected abnormal upper gut transit, gastric and small bowel transit scintigraphy followed by small intestinal (antroduodenojejunalileal) manometry is recommended. Small bowel manometry can identify patterns suggestive of myopathy, neuropathy or obstruction. Information on procedures, indications, significance, pitfalls and guidelines for small bowel manometry is provided in this paper. In this context the potentials of small intestinal manometry for scientific experimental study of neurohumoral agents, such as serotonin receptor agonists and antagonists, on small intestinal motility is presented.
Topics: Enteric Nervous System; Gastrointestinal Diseases; Gastrointestinal Motility; Humans; Intestine, Small; Manometry
PubMed: 12613464
DOI: No ID Found -
Frontiers in Immunology 2020Paneth cells were first described in the late 19th century by Gustav Schwalbe and Josef Paneth as columnar epithelial cells possessing prominent eosinophilic granules in... (Review)
Review
Paneth cells were first described in the late 19th century by Gustav Schwalbe and Josef Paneth as columnar epithelial cells possessing prominent eosinophilic granules in their cytoplasm. Decades later there is continued interest in Paneth cells as they play an integral role in maintaining intestinal homeostasis and modulating the physiology of the small intestine and its associated microbial flora. Paneth cells are highly specialized secretory epithelial cells located in the small intestinal crypts of Lieberkühn. The dense granules produced by Paneth cells contain an abundance of antimicrobial peptides and immunomodulating proteins that function to regulate the composition of the intestinal flora. This in turn plays a significant role in secondary regulation of the host microvasculature, the normal injury and repair mechanisms of the intestinal epithelial layer, and the levels of intestinal inflammation. These critical functions may have even more importance in the immature intestine of premature infants. While Paneth cells begin to develop in the middle of human gestation, they do not become immune competent or reach their adult density until closer to term gestation. This leaves preterm infants deficient in normal Paneth cell biology during the greatest window of susceptibility to develop intestinal pathology such as necrotizing enterocolitis (NEC). As 10% of infants worldwide are currently born prematurely, there is a significant population of infants contending with an inadequate cohort of Paneth cells. Infants who have developed NEC have decreased Paneth cell numbers compared to age-matched controls, and ablation of murine Paneth cells results in a NEC-like phenotype suggesting again that Paneth cell function is critical to homeostasis to the immature intestine. This review will provide an up to date and comprehensive look at Paneth cell ontogeny, the impact Paneth cells have on the host-microbial axis in the immature intestine, and the repercussions of Paneth cell dysfunction or loss on injury and repair mechanisms in the immature gut.
Topics: Animals; Enterocolitis, Necrotizing; Humans; Infant, Newborn; Infant, Premature; Intestine, Small; Paneth Cells
PubMed: 32308658
DOI: 10.3389/fimmu.2020.00587 -
Physiological Reports Feb 2021Obesity is associated with the development of insulin resistance (IR) and type-2 diabetes mellitus (T2DM); however, not all patients with T2DM are obese. The... (Comparative Study)
Comparative Study
BACKGROUND
Obesity is associated with the development of insulin resistance (IR) and type-2 diabetes mellitus (T2DM); however, not all patients with T2DM are obese. The Goto-Kakizaki (GK) rat is an experimental model of spontaneous and non-obese T2DM. There is evidence that the intestine contributes to IR development in GK animals. This information prompted us to investigate small intestine remodeling in this animal model.
METHODS
Four-month-old male Wistar (control) and GK rats were utilized for the present study. After removing the small intestine, the duodenum, proximal jejunum, and distal ileum were separated. We then measured villi and muscular and mucosa layer histomorphometry, goblet cells abundance, total myenteric and submucosal neuron populations, and inflammatory marker expression in the small intestinal segments and intestinal transit of both groups of animals.
KEY RESULTS
We found that the GK rats exhibited decreased intestinal area (p < 0.0001), decreased crypt depth in the duodenum (p = 0.01) and ileum (p < 0.0001), increased crypt depth in the jejunum (p < 0.0001), longer villi in the jejunum and ileum (p < 0.0001), thicker villi in the duodenum (p < 0.01) and ileum (p < 0.0001), thicker muscular layers in the duodenum, jejunum, and ileum (p < 0.0001), increased IL-1β concentrations in the duodenum and jejunum (p < 0.05), and increased concentrations of NF-κB p65 in the duodenum (p < 0.01), jejunum and ileum (p < 0.05). We observed high IL-1β reactivity in the muscle layer, myenteric neurons, and glial cells of the experimental group. GK rats also exhibited a significant reduction in submucosal neuron density in the jejunum and ileum, ganglionic hypertrophy in all intestinal segments studied (p < 0.0001), and a slower intestinal transit (about 25%) compared to controls.
CONCLUSIONS
The development of IR and T2DM in GK rats is associated with small intestine remodeling that includes marked alterations in small intestine morphology, local inflammation, and reduced intestinal transit.
Topics: Animals; Blood Glucose; Cytokines; Diabetes Mellitus, Type 2; Disease Models, Animal; Duodenum; Gastrointestinal Transit; Ileum; Inflammation Mediators; Insulin Resistance; Intestine, Small; Jejunum; Male; Myenteric Plexus; Rats, Wistar; Submucous Plexus; Rats
PubMed: 33580916
DOI: 10.14814/phy2.14755