Lung surfactant system

Shelley, S.A., Oxidant-induced alterations of lung surfactant system, J. Fla. Med. Assoc. 

Thus it is possible to estimate the time for surfactant adsorption required for the formation of black spots. Table 11.2 presents the clinical and threshold concentrations for total phospholipids (PL) and for disaturated phosphatidylcholine (DSPC) in each preparation. The most abundant PL of the lung surfactant system is DSPC, principally the DPPC species, which is believed the essential determinant of surfactant function in vivo [2], While DPPC is the only PL in EX, both IN and SU contain other PLs and small quantities of hydrophobic surfactant-associated proteins that may add to the desired functional properties of the material in situ. 

SURFACTANTS AS ACTIVE AGENTS 18.5.1 Lung Surfactant System... 

Phospholipids play an important role in lung functions. The surface active material to be found in the alveolar lining of the lung is a mixture of phospholipids, neutral lipids and proteins. Lowering of surface tension by the lung surfactant system and the surface elasticity of the surface layers assists alveolar expansion and contraction. Deficiency of lung surfactants in newborns leads to a respiratory distress syndrome and this led to the suggestion that instillation of phospholipid surfactants could cure the problem. 

For the treatment of lung surfactant deficiency in premature human infants suffering from respiratory distress syndrome, limited clinical trials were performed showing that liposomes in the lung-instilled intratracheally either as an aerosolized mist (Ivey et al., 1977) or as a suspension via an endotracheal tube (Fujiwara et al., 1980)—rapidly improved lung function. No adverse effects were observed as a result of the supplementation with surfactant-like material. It appears, therefore, that liposomes are a suitable system for the delivery of major phospholipid components of endogenous lung surfactant. 

Alfonso LF, Arnaiz A, Alvarez FJ, Qi BQ, Dies-Pardo JA, Vallisi-Soler A, Tovar JA (1996) Lung hypoplasia and surfactant system immaturity induced in the fetal rat by prenatal exposure to nitrofen. Biol Neonate 69 94-100... 

There are also several examples of natural surfactants and foams in the human body. The understanding of the pulmonary surfactant system, although discovered in 1929, has only been applied clinically since about 1990 for the treatment of respiratory distress syndrome. Surfactant replacement therapy may also be used in treating other forms of lung disease, such as meconium aspiration syndrome, neonatal pneumonia and congenital diaphragmatic hernia [881]. Lung surfactant, composed of phospholipids and proteins [882,883], is necessary to maintain a low surface tension at the alveolar air-liquid interface. When there is a deficiency of surfac-... 

The examples given here involve lung surfactant replacement compositions and surfactant systems used for 2D protein crystallization. Other potential systems include direct, reverse and multiple emulsions for drug and gene delivery, as well as micro- and nano-sized gas bubbles for O2 delivery and diagnosis [3, 4]... 

Cruewels L, Golde L, Haagsman H. The pulmonary surfactant system Biochemical and clinical aspects. Lung 1997, 175, 1-39. 

Hanes J, Evora C, Ben-Jebria A, Edwards DA, Langer R. Porous Dry-Powder PLGA Microspheres Coated with Lung Surfactant for Systemic Insulin Delivery via the Lung. Proceed Inter Symp Control Rel Bioact Mater 1997, 24, 57-58. 

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