Related Experiment Video
Updated: May 11, 2026
14:48
Visualizing Lung Cellular Adaptations during Combined Ozone and LPS Induced Murine Acute Lung Injury
Published on: March 21, 2021
Hyperosmolarity enhances the lung capillary barrier.
Zeenat Safdar1, Ping Wang, Hideo Ichimura
1Division of Pulmonary-Critical Care Medicine, St Luke's-Roosevelt Hospital Center, New York, New York 10019, USA.
The Journal of Clinical Investigation
|November 18, 2003
Summary
Hyperosmolar therapy using sucrose infusions enhanced lung capillary barriers by remodeling the actin cytoskeleton. This approach successfully blocked inflammatory injury and may offer new treatments for lung inflammatory diseases.
Area of Science:
- Pulmonary Medicine
- Cell Biology
- Biophysics
Background:
- Capillary barrier deterioration is a key factor in lung inflammatory diseases.
- Current strategies to enhance capillary barrier function are limited.
- Hyperosmolar therapy is explored as a potential barrier-enhancing strategy.
Purpose of the Study:
- To investigate the effects of hyperosmolar therapy on lung capillary barrier function.
- To determine the mechanisms underlying hyperosmolar-induced barrier enhancement.
- To assess the therapeutic potential of hyperosmolar therapy in lung inflammation.
Main Methods:
- Real-time imaging of lung venular capillaries in vivo.
- Infusion of hyperosmolar sucrose and assessment of capillary hydraulic conductivity.
- Evaluation of endothelial cell actin cytoskeleton and E-cadherin expression.
- Assessment of barrier integrity against inflammatory agents (thrombin, TNF-alpha, H2O2) and acid instillation.
- Use of actin-depolymerizing agent (latrunculin B) to probe mechanisms.
Main Results:
- Hyperosmolar sucrose infusions significantly enhanced lung capillary barrier function.
- Barrier enhancement was sufficient to prevent injury induced by thrombin, TNF-alpha, H2O2, and acid instillation.
- Hyperosmolarity increased actin filament formation and E-cadherin expression at endothelial cell junctions.
- Actin cytoskeleton remodeling was essential for hyperosmolar barrier enhancement and blocking TNF-alpha-induced P-selectin expression.
Conclusions:
- Hyperosmolar therapy effectively remodels the lung endothelial barrier and actin cytoskeleton.
- This remodeling enhances barrier properties and inhibits pro-inflammatory responses.
- Hyperosmolar therapy presents a promising strategy for managing lung inflammatory diseases.
Related Concept Videos
00:47Osmosis
Approximately 60% to 95% of the weight of living organisms is attributed to water. Therefore, maintaining appropriate water balance within cells is of paramount importance. Osmosis is the movement of water across a semipermeable membrane, such as a cell’s plasma membrane. In living organisms, water plays a crucial role as a solvent—a molecule that dissolves other molecules.
02:40Osmosis and Osmotic Pressure of Solutions
A number of natural and synthetic materials exhibit selective permeation, meaning that only molecules or ions of a certain size, shape, polarity, charge, and so forth, are capable of passing through (permeating) the material. Biological cell membranes provide elegant examples of selective permeation in nature, while dialysis tubing used to remove metabolic wastes from blood is a more simplistic technological example. Regardless of how they may be fabricated, these materials are generally...
01:23Transcellular Transport of Solutes
Transcellular transport of solutes is the movement of substances like monosaccharides and amino acids through polarized cells. This transport mechanism is primarily seen in epithelial and endothelial cells aided by membrane transport proteins such as channels and transporters. The tight junctions between these cells confine the membrane proteins to the two sides of the cell. The epithelial cells have distinct apical and basolateral domains. In contrast, the endothelial cells show the luminal...
01:30Osmosis
Osmosis is the movement of free water molecules through a semipermeable membrane. The water's concentration gradient across the membrane is inversely proportional to the solutes' concentration. Whereas diffusion transports material across membranes and within cells, osmosis transports only water across a membrane, and the membrane limits the diffusion of solutes in the water. Osmosis is a special case of diffusion.
Water, like other substances, moves from a high concentration of free water...
Water, like other substances, moves from a high concentration of free water...
01:28Capillary Exchange
The cardiovascular system's chief role is to disseminate gases, nutrients, waste, and other substances to the body's cells. Small molecules like gases, lipids, and lipid-soluble substances directly diffuse through capillary wall endothelial cell membranes. Glucose, amino acids, and ions, including sodium, potassium, calcium, and chloride, use transporters for facilitated diffusion via membrane-specific channels. Glucose, ions, and bigger molecules may also pass through intercellular clefts.
01:18Pulmonary Edema II: Pathophysiology
Pulmonary edema is the accumulation of fluid in the interstitial and alveolar spaces of the lungs, impairing gas exchange and oxygen delivery. It may be cardiogenic or noncardiogenic, but both reduce oxygenation and lung compliance.Cardiogenic Pulmonary EdemaCardiogenic edema results from increased hydrostatic pressure in pulmonary capillaries, usually due to left ventricular dysfunction from myocardial infarction, heart failure, or valvular disease. Ineffective cardiac pumping causes blood to...