Background: Intestinal mucus not only facilitates substrate absorption, but also forms a hydrophobic, phosphatidylcholine (PC) enriched, barrier against luminal gut contents.
Methods: For evaluation of the origin of PC in intestinal mucus, we first analyzed the mucus PC in mice with absent biliary phospholipid secretion (mdr2 (-/-) mice) using electrospray ionization (ESI) tandem mass spectroscopy (MS/MS). Second, in situ perfused rat jejunum, ileum and colon were analyzed after i.v. bolus injections of 155 pmol [(3)H]-PC. Additional in vitro experiments were performed with isolated mucosal cells after incubation with the PC precursor [(3)H]-choline.
Results: In mdr2 (-/-) mice and control animals no significant quantitative difference in mucus PC was found, indicating that mucus PC is of intestinal and not biliary origin. In situ perfusion studies detected intestinal secretion of [(3)H]-PC, which was stimulated in presence of 2 mM taurocholate (TC). Secretion rates of [(3)H]-PC were highest in ileum (9.0+/-0.8 fmol h(-1)xcm(-1)), lower in jejunum (4.3+/-0.5) and minimal in colon (0.8+/-0.2). It compares to an intestinal secretion of native PC originating to 64% from bile, 9% from jejunum, 28% from ileum, and 1% from colon. Complementary in vitro studies showed 30-min secretion rates for [(3)H]-PC to be highest in enterocytes from ileum (26.5+/-5.3% of intracellular [(3)H]-PC) and jejunum (19.8+/-2.9%), and significantly lower in colonocytes (8.4+/-1.3%).
Conclusion: PC in the intestinal mucus originates from secretion by ileal and jejunal enterocytes.
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http://dx.doi.org/10.1016/j.bbalip.2004.01.009 | DOI Listing |
Nagoya J Med Sci
November 2024
Department of Pathology, Japanese Red Cross Aichi Medical Center Nagoya Daiichi Hospital, Nagoya, Japan.
A 54-year-old woman was referred to our hospital because of abnormal colonoscopic findings, including a submucosal protuberance at the appendiceal root. A biopsy showed no malignant findings. Computed tomography revealed a 20-mm cystic lesion with thick walls at the appendiceal root, suggestive of an appendiceal mucocele.
View Article and Find Full Text PDFChemosphere
January 2025
Department of Agriculture and Allied Science, CV Raman Global University, Bhubaneswar, Odisha, India. Electronic address:
The pace of research efforts has been extraordinarily accelerated across the globe to address the contamination issues caused by pesticides, and fertilizers, especially in the aquatic ecosystem. The sole aim of this study was to assess the effect of urea on Nile Tilapia (Oreochromis niloticus). For this purpose, the fish fingerlings were exposed to increasing concentrations of urea such as 0, 1, 2.
View Article and Find Full Text PDFActa Histochem Cytochem
December 2024
Department of Anatomy, School of Medicine, University of Occupational and Environmental Health, 1-1, Iseigaoka, Yahatanishi, Kitakyushu, Fukuoka 807-8555, Japan.
Inflammatory bowel disease is triggered by abnormalities in epithelial barrier function and immunological responses, although its pathogenesis is poorly understood. The dextran sodium sulphate (DSS)-induced colitis model has been used to examine inflammation in the colon. Damage to mucosa primality occurs in the large intestine and scarcely in the small intestine.
View Article and Find Full Text PDFFront Pharmacol
December 2024
School of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, China.
Introduction: The aim of this study is to examine the physiological effects of emodin on intestinal microorganisms and the liver in the BALb/c mice.
Method And Results: Following an 8-week administration of emodin at doses of 25, 50, and 100 mg/kg/day,pathological analyses revealed that emodin significantly reduced the colon length, induced colonic crypt inflammation,diminished the colonic mucus layer,and decreased the fluorescence intensity of colonic tight junction proteins ZO-1 and Occludin. Concurrently, 16S rDNA gene sequencing corroborated that emodin altered the diversity and composition of the intestinal microbiota by increasing the to ratio.
Int J Mol Sci
December 2024
Research Unit of Biomedicine and Internal Medicine, University of Oulu, 902 20 Oulu, Finland.
Mucins 5AC (MUC5AC) and 5B (MUC5B) are the major mucins providing the organizing framework for the airway's mucus gel. We retrieved bronchial mucosal biopsies and bronchial wash (BW) samples through bronchoscopy from patients with chronic obstructive pulmonary disease ( = 38), healthy never-smokers ( = 40), and smokers with normal lung function ( = 40). The expression of MUC5AC and MUC5B was assessed immunohistochemically.
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