Localization of the Lipid Receptors CD36 and CLA-1/SR-BI in the Human Gastrointestinal Tract: Towards the Identification of Receptors Mediating the Intestinal Absorption of Dietary Lipids

Autor: Lydia Huerta, Emma Teixeiro, Angel Celdrán, Maria V.T. Lobo, Paloma de la Cueva, Miguel A. Vega, Rafael Bragado, Antonia Martín–Hidalgo, Natividad Ruiz–Velasco
Rok vydání: 2001
Předmět:
Antigens
Differentiation
T-Lymphocyte
CD36 Antigens
Histology
Colon
Duodenum
CD36
Fluorescent Antibody Technique
Biology
Intestinal absorption
Jejunum
03 medical and health sciences
0302 clinical medicine
Antigens
Neoplasm
Ileum
medicine
Humans
RNA
Messenger
Intestinal Mucosa
Receptors
Immunologic
Receptor
Receptors
Lipoprotein
Receptors
Scavenger
Membrane Glycoproteins
Intestinal lipid absorption
Human gastrointestinal tract
Membrane Proteins
food and beverages
Scavenger Receptors
Class B
Apical membrane
Blotting
Northern
Dietary Fats
Molecular biology
medicine.anatomical_structure
Intestinal Absorption
Biochemistry
Gastric Mucosa
Organ Specificity
Caco-2
030220 oncology & carcinogenesis
biology.protein
lipids (amino acids
peptides
and proteins)
030211 gastroenterology & hepatology
Caco-2 Cells
Anatomy
Digestive System
Zdroj: Journal of Histochemistry & Cytochemistry. 49:1253-1260
ISSN: 1551-5044
0022-1554
Popis: The scavenger receptors CLA-1/SR-BI and CD36 interact with native and modified lipoproteins and with some anionic phospholipids. In addition, CD36 binds/transports long-chain free fatty acids. Recent biochemical evidences indicates that the rabbit CLA-1/SR-BI receptor can be detected in enterocytes, and previous studies showed the presence of mRNA for both CLA-1/SR-BI and CD36 in some segments of the intestinal tract. These findings prompted us to study their respective localization and distribution from the human stomach to the colorectal segments, using immunohistochemical methods. Their expression in the colorectal carcinoma-derived cell line Caco-2 was analyzed by Northern blotting. In the human intestinal tract, CLA-1/SR-BI was found in the brush-border membrane of enterocytes from the duodenum to the rectum. However, CD36 was found only in the duodenal and jejunal epithelium, whereas enterocytes from other intestinal segments were not stained. In the duodenum and jejunum, CD36 co-localized with CLA-1/SR-BI in the apical membrane of enterocytes. The gastric epithelium was immunonegative for both glycoproteins. We also found that CLA-1/SR-BI mRNA was expressed in Caco-2 cells and that its expression levels increased concomitantly with their differentiation. In contrast, the CD36 transcript was not found in this colon cell line, in agreement with the absence of this protein in colon epithelium. The specific localization of CLA-1/SR-BI and CD36 along the human gastrointestinal tract and their ability to interact with a large variety of lipids strongly support a physiological role for them in absorption of dietary lipids.
Databáze: OpenAIRE
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