Effects of the Human Pulmonary Surfactant Protein-C (SP-C), SP-CL16(6—28) on Surface Activities of Surfactants with Various Phospholipids

• Published in: Biological & pharmaceutical bulletin Vol. 25; no. 10; pp. 1303 - 1306
• Main Authors: Otsubo, Eiji, Takei, Tsunetomo
• Format: Journal Article
• Language: English
• Published: Tokyo The Pharmaceutical Society of Japan 01-10-2002; Maruzen; Japan Science and Technology Agency
• Subjects: Animals; Biological and medical sciences; Humans; Leucine - chemistry; Leucine - pharmacology; Lung Volume Measurements - methods; Medical sciences; Peptides - chemistry; Peptides - pharmacology; Pharmacology. Drug treatments; Phosphatidylglycerols - chemistry; Phosphatidylglycerols - pharmacology; Phospholipids - chemistry; Phospholipids - pharmacology; Phospholipids - therapeutic use; Pulmonary Surfactant-Associated Protein C - analogs & derivatives; Pulmonary Surfactant-Associated Protein C - pharmacology; Pulmonary Surfactant-Associated Protein C - therapeutic use; Pulmonary Surfactants - chemistry; Pulmonary Surfactants - pharmacology; Pulmonary Surfactants - therapeutic use; Rabbits; Respiratory system; SP-CL16(6—28); surface activity; surfactant protein-C; various phospholipid; Human; Lung; Rabbit; Protein C; Lagomorpha; Respiratory system; In vitro; Biological activity; In vivo; Vertebrata; Mammalia; Structure activity relation; Pulmonary surfactant; Analog; Animal; Mechanism of action
• ISSN: 0918-6158; 1347-5215
• DOI: 10.1248/bpb.25.1303

We previously reported that a human analogue of pulmonary surfactant protein-C (SP-C), SP-CL16(6—28), with 23 residues was the most active analogue in a reconstituted lipid mixture and had the shortest chain among the poly-leucine-analogues examined. There has been little research on the chemical components of synthetic lung surfactants (SLSs). In the present study, we attempted to compare SLS with various phospholipids in surface activity. That is, SP-CL16(6—28) plus various phosphatidylglycerols (PG) were tested for surface activity in a Langmuir–Wilhelmy surface balance (WSB) apparatus and pulsating bubble surfactmeter (PBS). Further, SLSs were examined for biological properties using an animal model of surfactant deficiency, infant respiratory distress syndrome (IRDS), in vivo. Palmitoyl-oleoyl-phosphatidylglycerol (POPG)-SLS exhibited minimum and maximum surface tensions of 1.7 mN/m and 28.6 mN/m in WSB and 8.5 mN/m and 36.2 mN/m in PBS, respectively. Moreover, in the IRDS model, POPG-SLS remarkably improved the lung volume (LV) of a premature lagomorph fetus at LV30 cmH2O and LV5 cmH2O. That is, a significant improvement equal to the LV of a full-term fetus was observed. The level of LV exhibited respiratory improvement equivalent to surfactant-TA. SLS seemed comparable in surface activity with Surfacten® (Surfactant-TA), a modified surfactant preparation which has been used for the treatment of RDS.