Aim: Study of tight junction state and ultrastructure changes of rat jejunum enterocytes and colon colonocytes under the effect of cholerogen and protamine.

Materials And Methods: Cholerogen (cholera toxin, Sigma-Aldrich, Germany) and protamine sulfate (Russia) were used in the study. The study was carried out in Wistar line rats. Effect of cholera toxin and protamine on rat intestine epitheliocytes was carried out by incubating intestine segments in the respective solutions. Ultrastructure changes caused by cholerogen and protamine in rat enterocytes and colonocytes were assessed based on ultrathin section analysis by transmission electron microscopy of the cells themselves and tight junctions between them compared with control.

Results: Effect of cholerogen on intestine mucous membrane epitheliocytes manifested in changes of cell ultrastructure, the form of which transformed as a result of increase of intercellular space without the destruction of tight junctions. Disappearance of cell plasma membrane lateral area folding and decrease of number of microvilli was noted. Enlargement of nuclei was noted only in individual cells. Effect of protamine on epithelial cell layer ultrastructure differed significantly from the effect of cholerogen. Increase of cell plasma membrane lateral area folding and significant enlargement of nuclei that moved to the central part of cells reaching its apical end were characteristic effects for protamine. Surface of a part of epitheliocytes lost microvilli with simultaneous destruction of tight junction structure. Protamine induced increase of folding only in colon without affecting jejunum. At the same time both of these substances caused increase of intercellular space in jejenum and colon epithelium.

Conclusion: Differences in ultrathin structure of rat small intestine and colon epitheliocyte tight junctions under the effect of cholerogen and protamine were revealed.

Download full-text PDF

Source

Publication Analysis

Top Keywords

tight junctions
16
cholerogen protamine
12
protamine
8
rat enterocytes
8
tight junction
8
ultrastructure changes
8
cholera toxin
8
protamine rat
8
increase intercellular
8
intercellular space
8

Similar Publications

Ion permeability profiles of renal paracellular channel-forming claudins.

Acta Physiol (Oxf)

February 2025

Clinical Physiology/Nutritional Medicine, Medical Department, Division of Gastroenterology, Infectiology, Rheumatology, Charité-Universitätsmedizin Berlin, Berlin, Germany.

Aim: Members of the claudin protein family are the major constituents of tight junction strands and determine the permeability properties of the paracellular pathway. In the kidney, each nephron segment expresses a distinct subset of claudins that form either barriers against paracellular solute transport or charge- and size-selective paracellular channels. It was the aim of the present study to determine and compare the permeation properties of these renal paracellular ion channel-forming claudins.

View Article and Find Full Text PDF

Cold atmospheric plasma (CAP) has been utilized in various medical devices using its oxidative nature. Recent studies have provided evidence that CAP can facilitate the delivery of large, hydrophilic molecules through the epidermis to the dermis. On the other hand, a new approach called low-intensity CAP (LICAP) has been developed, allowing the plasma level to be controlled within a subtoxic range, thereby demonstrating various biological benefits without tissue damage.

View Article and Find Full Text PDF

dampens SUMOylation and promotes intestinal inflammation.

Gut Microbes

December 2025

Univ Rouen Normandie, INSERM, Normandie Univ, ADEN, UMR 1073 Nutrition, Inflammation and Microbiota-Gut-Brain axis, Rouen, France.

Gut bacteria play key roles in intestinal physiology, via the secretion of diversified bacterial effectors. Many of these effectors remodel the host proteome, either by altering transcription or by regulating protein post-translational modifications. SUMOylation, a ubiquitin-like post-translational modification playing key roles in intestinal physiology, is a target of gut bacteria.

View Article and Find Full Text PDF

Oral Biomimetic Nanotherapeutics for Ulcerative Colitis Targeted Treatment by Repairing Intestinal Epithelial Barrier and Restoring Redox Homeostasis.

ACS Appl Mater Interfaces

January 2025

Department of Pharmaceutics, School of Pharmacy, Ningxia Medical University, No. 1160 Shengli South Street, Yinchuan 750004, PR China.

The structural disruption of intestinal barrier and excessive reactive oxygen/nitrogen species (RONS) generation are two intertwined factors that drive the occurrence and development of ulcerative colitis (UC). Synchronously restoring the intestinal barrier and mitigating excess RONS is a promising strategy for UC management, but its treatment outcomes are still hindered by low drug accumulation and retention in colonic lesions. Inspired by intestine colonizing bacterium, we developed a mucoadhesive probiotic -mimic entinostat-loaded hollow mesopores prussian blue (HMPB) nanotherapeutic (AM@HMPB@E) for UC-targeted therapy via repairing intestinal barrier and scavenging RONS.

View Article and Find Full Text PDF

A 3D Model of the Human Lung Airway for Evaluating Permeability of Inhaled Drugs.

ACS Pharmacol Transl Sci

January 2025

Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research, United States Food and Drug Administration (FDA), Silver Spring, Maryland 20993, United States.

Current in vitro cell-based methods, relying on single cell types, have structural and functional limitations in determining lung drug permeability, which is a contributing factor affecting both local and systemic drug levels. To address this issue, we investigated a 3D human lung airway model generated using a cell culture insert, wherein primary human lung epithelial and endothelial cells were cocultured at an air-liquid interface (ALI). To ensure that the cell culture mimics the physiological and functional characteristics of airway tissue, the model was characterized by evaluating several parameters such as cellular confluency, ciliation, tight junctions, mucus-layer formation, transepithelial electrical resistance, and barrier function through assaying fluorescein isothiocyanate-dextran permeability.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!